Article

SunShot Solar Power Reduces Costs and Uncertainty in Future Low-Carbon Electricity Systems

Authors:
  • Blue Marble Analytics
  • Daikin U.S. Corporation
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Abstract

The United States Department of Energy's SunShot Initiative has set cost-reduction targets of $1/watt for central-station solar technologies. We use SWITCH, a high-resolution electricity system planning model, to study the implications of achieving these targets for technology deployment and electricity costs in western North America, focusing on scenarios limiting carbon emissions to 80% below 1990 levels by 2050. We find that achieving the SunShot target for solar photovoltaics would allow this technology to provide more than a third of electric power in the region, displacing natural gas in the medium term and reducing the need for nuclear and carbon capture and sequestration (CCS) technologies, which face technological and cost uncertainties, by 2050. We demonstrate that a diverse portfolio of technological options can help integrate high levels of solar generation successfully and cost-effectively. The deployment of GW-scale storage plays a central role in facilitating solar deployment and the availability of flexible loads could increase the solar penetration level further. In the scenarios investigated, achieving the SunShot target can substantially mitigate the cost of implementing a carbon cap, decreasing power costs by up to 14% and saving up to $20 billion ($2010) annually by 2050 relative to scenarios with Reference solar costs.

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... For many experts, energy storage technology is considered one of the disruptive technology that could change the way we generate and consume energy. In the past decades [1][2][3][4][5][6][7][8][9][10][11][12][13][14][15][16][17][18], several research activities dealing with some scenarios of low-carbon energy future have somehow examined the role of energy storage technology in the corresponding systems. Many researchers [1][2][3][4][5][6][7][8][9][10] estimated storage capacity requirements for renewable energy based grids that dominantly depends on wind and solar. ...
... In the past decades [1][2][3][4][5][6][7][8][9][10][11][12][13][14][15][16][17][18], several research activities dealing with some scenarios of low-carbon energy future have somehow examined the role of energy storage technology in the corresponding systems. Many researchers [1][2][3][4][5][6][7][8][9][10] estimated storage capacity requirements for renewable energy based grids that dominantly depends on wind and solar. These studies uses diverging methodologies for modeling while also studying the cases at different geographic regions. ...
... As regards to modelling techniques, we could have three major categories. Namely, (i) those estimating required energy capacity for very high shares of renewable energy with no or little attention to the power capacity of storage [1][2][3]; (ii) economic models assessing storage as a key technology in a low-carbon energy future [4][5][6][7][8][9][10][11]; and (iii) those studying factors affecting storage design and the corresponding capacity requirements [12][13][14][15]. As regards to the diversities in geographic location, it is possible to find studies covering several parts of the world such as entire regions (or a part) of Europe [1,2,5,9], Japan [3], Kingdom of Saudi Arabia (KSA) [6], Asia [7], Israel [12,13], USA [4,10,[14][15][16]]. ...
... In the past decades [1][2][3][4][5][6][7][8][9][10][11][12][13][14][15][16][17][18], several research activities dealing with some scenarios of low-carbon energy future have somehow examined the role of energy storage technology in the corresponding systems. Many researchers [1][2][3][4][5][6][7][8][9][10] estimated storage capacity requirements for renewable energy based grids that dominantly depends on wind and solar. These studies uses diverging methodologies ...
... For many experts, energy storage technology is considered one of the disruptive technologies that could change the way we generate and consume energy. In the past decades [1][2][3][4][5][6][7][8][9][10][11][12][13][14][15][16][17][18], several research activities dealing with some scenarios of low-carbon energy future have somehow examined the role of energy storage technology in the corresponding systems. Many researchers [1][2][3][4][5][6][7][8][9][10] estimated storage capacity requirements for renewable energy based grids that dominantly depends on wind and solar. ...
... In the past decades [1][2][3][4][5][6][7][8][9][10][11][12][13][14][15][16][17][18], several research activities dealing with some scenarios of low-carbon energy future have somehow examined the role of energy storage technology in the corresponding systems. Many researchers [1][2][3][4][5][6][7][8][9][10] estimated storage capacity requirements for renewable energy based grids that dominantly depends on wind and solar. These studies uses diverging methodologies for modeling while also studying the cases at different geographic regions. ...
Article
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In this paper, we present issues of electricity storage requirements based on comparative studies of various results. It was found that when we increase energy from VRE, the use of storage and its capacity increases until we reach some threshold. After that threshold, the storage use starts to decline even if we increase the size. An optimally utilized storage of about daily average demand would be sufficient to reach grid penetration of about 90% of the total demands from VRE. The understanding of the physics and economics of the future energy system is mandatory to build and operate it optimally.
... In the past decades [1][2][3][4][5][6][7][8][9][10][11][12][13][14][15][16][17][18], several research activities dealing with some scenarios of low-carbon energy future have somehow examined the role of energy storage technology in the corresponding systems. Many researchers [1][2][3][4][5][6][7][8][9][10] estimated storage capacity requirements for renewable energy based grids that dominantly depends on wind and solar. These studies uses diverging methodologies ...
... For many experts, energy storage technology is considered one of the disruptive technologies that could change the way we generate and consume energy. In the past decades [1][2][3][4][5][6][7][8][9][10][11][12][13][14][15][16][17][18], several research activities dealing with some scenarios of low-carbon energy future have somehow examined the role of energy storage technology in the corresponding systems. Many researchers [1][2][3][4][5][6][7][8][9][10] estimated storage capacity requirements for renewable energy based grids that dominantly depends on wind and solar. ...
... In the past decades [1][2][3][4][5][6][7][8][9][10][11][12][13][14][15][16][17][18], several research activities dealing with some scenarios of low-carbon energy future have somehow examined the role of energy storage technology in the corresponding systems. Many researchers [1][2][3][4][5][6][7][8][9][10] estimated storage capacity requirements for renewable energy based grids that dominantly depends on wind and solar. These studies uses diverging methodologies for modeling while also studying the cases at different geographic regions. ...
Conference Paper
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In this paper, we present issues of electricity storage requirements based on comparative studies of various results. Studies using the datasets of Israel and California show that the storage requirement was defined by the seasonal and diurnal patterns of the local demand, and the corresponding variable renewable energy (VRE) resources profile. It was found that when we increase energy supply from VRE, the use of storage and its capacity increases until we reach some threshold. After that threshold, the storage use starts to decline even if we increase the size. An optimally utilized storage of about daily average demand would be sufficient to reach grid penetration of about 90% of the total demands from VRE at 20% total energy loss. Optimizing with other RE resources will be necessary to reach a net zero energy system instead of pushing for penetration of 100% VRE, which will require larger storage size at reduced storage usability. A loose approximation shows that the largest storage requirement for such a VRE was of the order of 6 times average daily demand with a modest increase in energy loss. A diverse Finnish 100% RE system (with 70% from VRE) was reported with energy storage size of about 8.6 times average daily demand and 6% total loss. At similar loss, the same penetration was achieved by a storage size of 0.5 times daily average demand in California, suggesting further optimization in the Finish system could result in further reduction in storage with some increase in curtailment, but might lead to higher total system cost. It was also noted that the mismatch between the VRE and load profile leads to least efficient use of resources if 100% VRE grid was aspired. However, optimal designing for VRE penetration up to 90% complemented with other renewable resources could provide an efficient energy system relying on lower storage size and balancing. We conclude that understanding of the physics and economics of the future energy system is mandatory to build and operate it optimally.
... We use SWITCH, an open source optimization model for planning power system investments and operations, for investigating least-cost and low-carbon pathways for Nicaragua. SWITCH identifies generation investment plans that minimize the cost of delivering power, every hour, to every load zone in a country, subject to operational and policy constraints, while explicitly accounting for the hourly variability of intermittent renewable energy (Fripp 2012, Nelson et al 2012, Mileva et al 2013. Open access timesynchronized hourly national electricity demand (subdivided into sixteen load zones), hourly-generation profiles for every generating unit in the country, and spatio-temporal renewable energy resource potentials, in addition to power system costs (generation, storage, and transmission costs) are all used in this analysis. ...
... Within this vein, we use SWITCH, an open source capacity planning and dispatch model of the electric power sector. SWITCH is unprecedented in its use of high-resolution spatial and temporal data to realistically model power systems and plan long-term capacity expansion 30-50 years into the future (Fripp 2012, Nelson et al 2012, Mileva et al 2013. The SWITCH model is an improvement from previous electric power system models as it bridges two prevailing but largely separate methodologies in energy planning: the detailed evaluation of daily grid operations and costs under high penetrations of solar and wind generation, and detailed analysis on how the grid could be developed to achieve near-and long-term policy objectives at the lowest cost. ...
... Four four-year-long investment periods: 2014-2017, 2018-2021, 2022-2025, and 2026-2029, each containing data from 12 months, two days per month, and 12 h per day are used to investigate a range of expansion plans over the next two decades. Peak and median load days are weighted differently (peak load days are given a weight of one day per month, and median days, are given a weight reflecting the remaining days in the month) to represent load and weather variability, as well as to ensure that the system is dispatching under typical load conditions, while incorporating capacity requirements for periods of high grid stress (Fripp 2012, Nelson et al 2012, Mileva et al 2013. ...
Article
Full-text available
The global carbon emissions budget over the next decades depends critically on the choices made by fast-growing emerging economies. Few studies exist, however, that develop country-specific energy system integration insights that can inform emerging economies in this decision-making process. High spatial- and temporal-resolution power system planning is central to evaluating decarbonization scenarios, but obtaining the required data and models can be cost prohibitive, especially for researchers in low, lower-middle income economies. Here, we use Nicaragua as a case study to highlight the importance of high-resolution open access data and modeling platforms to evaluate fuel-switching strategies and their resulting cost of power under realistic technology, policy, and cost scenarios (2014–2030). Our results suggest that Nicaragua could cost-effectively achieve a low-carbon grid (≥80%, based on non-large hydro renewable energy generation) by 2030 while also pursuing multiple development objectives. Regional cooperation (balancing) enables the highest wind and solar generation (18% and 3% by 2030, respectively), at the least cost (US$127 MWh−1). Potentially risky resources (geothermal and hydropower) raise system costs but do not significantly hinder decarbonization. Oil price sensitivity scenarios suggest renewable energy to be a more cost-effective long-term investment than fuel oil, even under the assumption of prevailing cheap oil prices. Nicaragua’s options illustrate the opportunities and challenges of power system decarbonization for emerging economies, and the key role that open access data and modeling platforms can play in helping develop low-carbon transition pathways.
... As noted above, leakage rates of roughly 3% per year can "flip" CH 4 from a fuel cleaner than coal in immediate global warming impact to emissions larger than a conventional coal-fired power plant (see also Allen et al., 2013;Brandt et al., 2014;Howarth et al., 2011;Karion et al., 2013;Kort et al., 2008;Pétron et al., 2014;Schneising et al., 2014;and U.S. EPA 2013and U.S. EPA , 2014and U.S. EPA , 2015b. To assess the impacts of leakage on the roles of natural gas in an integrated portfolio that includes large amounts of renewable power, a series of scenarios was run within the SWITCH-WECC model to identify least-cost electric power grids capable of meeting emissions goals (Fripp 2012;Mileva et al., 2013;Nelson et al., 2012). SWITCH-WECC includes a detailed representation of existing generators, storage facilities, and transmission lines in the Western Electricity Coordinating Council (WECC), which roughly spans the western portion of North America but does not explicitly model natural gas wells, pipelines, or related infrastructure. ...
... However, in 2017 U.S. DOE announced that the solar industry had already achieved the SunShot Initiative 2020 solar cost targets, bringing the costs of utility-scale solar to $0.06 per kWh. Models of the impact of this price change on the U.S. energy sector suggest solar power can cost effectively provide up to about one-third of national electricity capacity by midcentury (Mileva et al., 2013). The rapid deployment of distributed generational solar power systems over the past 5 to 10 years has both highlighted challenges and demonstrated many successful examples of integrating higher penetration levels than previously thought possible (Palmintier et al., 2016). ...
Chapter
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KEY FINDINGS 1. In 2013, primary energy use in North America exceeded 125 exajoules,1 of which Canada was responsible for 11.9%, Mexico 6.5%, and the United States 81.6%. Of total primary energy sources, approximately 81% was from fossil fuels, which contributed to carbon dioxide equivalent (CO2e)2 emissions levels, exceeding 1.76 petagrams of carbon, or about 20% of the global total for energy-related activities. Of these emissions, coal accounted for 28%, oil 44%, and natural gas 28% (very high confidence, likely). 2. North American energy-related CO2e emissions have declined at an average rate of about 1% per year, or about 19.4 teragrams CO2e, from 2003 to 2014 (very high confidence). 3. The shifts in North American energy use and CO2e emissions have been driven by factors such as 1) lower energy use, initially as a response to the global financial crisis of 2007 to 2008 (high confidence, very likely); but increasingly due to 2) greater energy efficiency, which has reduced the regional energy intensity of economic production by about 1.5% annually from 2004 to 2013, enabling economic growth while lowering energy CO2e emissions. Energy intensity has fallen annually by 1.6% in the United States and 1.5% in Canada (very high confidence, very likely). Further factors driving lower carbon intensities include 3) increased renewable energy production (up 220 petajoules annually from 2004 to 2013, translating to an 11% annual average increase in renewables) (high confidence, very likely); 4) a shift to natural gas from coal sources for industrial and electricity production (high confidence, likely); and 5) a wide range of new technologies, including, for example, alternative fuel vehicles (high confidence, likely). 4. A wide range of plausible futures exists for the North American energy system in regard to carbon emissions. Forecasts to 2040, based on current policies and technologies, suggest a range of carbon emissions levels from an increase of over 10% to a decrease of over 14% (from 2015 carbon emissions levels). Exploratory and backcasting approaches suggest that the North American energy system emissions will not decrease by more than 13% (compared with 2015 levels) without both technological advances and changes in policy. For the United States, however, decreases in emissions could plausibly meet a national contribution to a global pathway consistent with a target of warming to 2°C at a cumulative cost of $1 trillion to $4 trillion (US$ 2005).
... A number of assessments of the technical feasibility and economic impact of meeting both the AB32 and SB32 goals have been completed and are underway. In the energy system modeling work at UC Berkeley, UC Davis, and elsewhere, researchers found that a diverse set of pathways are possible that all meet the 2020, 2030, 2040, and 2050 climate goals [2,3]. We use the SWITCH model (http://rael.berkeley.edu/project/SWITCH) ...
... An important synergy between California's climate targets and economic growth is the ability of clean energy scenarios to create jobs and spur economic growth. In Figure 2: Example energy scenarios for California and Western North America that achieve 80% greenhouse gas emissions reductions in the electricity sector in 2050 generated with the SWITCH power system capacity expansion modeling tool [3,4]. ...
Article
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Scaling-up solutions require learning and adapting lessons between locations and at different scales. To accomplish this, common metrics are vital to building a shared language. For California, this has meant careful financial, cradle-to-grave life-cycle assessment methods leading to carbon accounting in many avenues of government (via the Low Carbon Fuel Standard or the Cap and Trade program). These methods themselves interact, such as the use of carbon accounting for the resources needed to manage water and other key resources; the use of criteria air pollution monitoring to identify environmental injustices; and the use of carbon market revenues to address these inequalities, through investment in best available abatement technologies (BACT) and in job creation in disadvantaged communities anticipated in the emerging clean energy sector. Creating interdisciplinary partnerships across the UC Campuses and the National Laboratories to innovate science and technology is critical to scalable carbon neutrality solutions. As an example, we can build coordinated research and development programs across UC and California, with strong partnerships with the Federal government to coordinate and “multiply” resources that accelerate development and deployment. These partnerships should be strongly goal-focused, i.e., they are created to solve specific, large problems, to enable quantitatively measurable outcomes within energy generation, efficiency and CO2 abatement categories. Intersectoral partnerships should be fostered across campuses, laboratories, with state, federal and multi-lateral organizations funding to develop technologies and deploy solutions at scale. Integrated partnerships with industry are required to influence markets, deploy solutions, and create new industries and jobs. Beyond California, we need to establish consortia with industry and foundations to deploy solutions at the regional, state, national, and international scale to create new industries, new jobs, and further UC and California’s leadership position. Significant economic opportunities exist, such as promoting aggressive electric vehicle programs elsewhere in the world, where California-based companies could play a key role on many fronts, via electric vehicles themselves, but also through building-integrated smart meters, inverters, solar and other clean energy generation technologies. All work must include a focus on environmental justice both at home in California and through global partnerships.
... Many research groups have further developed different versions of the SWITCH model to analyze decarbonization pathways in different regions 1,[37][38][39][59][60][61][62][63][64] . We use the SWITCH WECC 65 model which represents the Western Interconnection by dividing it into 50 geographical zones. ...
Article
Full-text available
As the world races to decarbonize power systems to mitigate climate change, the body of research analyzing paths to zero emissions electricity grids has substantially grown. Although studies typically include commercially available technologies, few of them consider offshore wind and wave energy as contenders in future zero-emissions grids. Here, we model with high geographic resolution both offshore wind and wave energy as independent technologies with the possibility of collocation in a power system capacity expansion model of the Western Interconnection with zero emissions by 2050. In this work, we identify cost targets for offshore wind and wave energy to become cost effective, calculate a 17% reduction in total installed capacity by 2050 when offshore wind and wave energy are fully deployed, and show how curtailment, generation, and transmission change as offshore wind and wave energy deployment increase.
... In the face of the Paris climate agreement, a combined transition to clean energy and acceleration of decarbonization goals will require the refocusing international research and deployment schemes to promote energy R&D (research and development) [30]. Dramatic cost declines in solar and wind technologies, and now energy storage, open the door to a reconceptualization of the roles of research and deployment of electricity production, transmission, and consumption that enable a clean energy transition [31]. The solar photovoltaic industry has undergone a dramatic evolution over the past decade. ...
... The SunShot initiative was a collaborative national effort launched by the DOE in 2011 which aggressively drove the cost reduction of solar energy to become cost-competitive with traditional energy sources. The target was to minimize solar power cost to $1/W or $0.06/kWh for central station systems and $1.5/W for residential systems by the year 2020 [91] and to reduce carbon emission to 20% of 1990 level by 2050 [92]. In 2017, the DOE announced that the target of $1/W was achieved three years before the targeted year. ...
Article
Full-text available
The ambitious target of net-zero emission by 2050 has been aggressively driving the renewable energy sector in many countries. Leading the race of renewable energy sources is solar energy, the fastest growing energy source at present. The solar industry has witnessed more growth in the last decade than it has in the past 40 years, owing to its technological advancements, plummeting costs, and lucrative incentives. The United States is one of the largest producers of solar power in the world and has been a pioneer in solar adoption, with major projects across different technologies, mainly photovoltaic, concentrated solar power, and solar heating and cooling, but is expanding towards floating PV, solar combined with storage, and hybrid power plants. Although the United States has tremendous potential for exploiting solar resources, there is a scarcity of research that details the U.S. solar energy scenario. This paper provides a comprehensive review of solar energy in the U.S., highlighting the drivers of the solar industry in terms of technology, financial incentives, and strategies to overcome challenges. It also discusses the prospects of the future solar market based on extensive background research and the latest statistics. In addition, the paper categorizes the U.S. states into five tiers based on their solar prospects calculated using analytical hierarchy process and regression analysis. The price of solar technologies in the U.S. is also predicted up to 2031 using Wright’s law, which projected a 77% reduction in the next decade.
... The model incorporates a combination of current and advanced grid assets. Optimization is subject to reliability, constraints on operations, and resource availability, as well as on current and potential climate policies and environmental regulations (Fripp, 2012;Johnston et al., 2019;Mileva et al., 2013;Nelson et al., 2012;Sanchez et al., 2015). SWITCH-China's modeling decisions regarding system expansion are based on optimizing capital costs, operation and maintenance costs, and variable costs for installed power plant capacities and transmission lines. ...
Article
Deep carbon mitigation and water resources conservation are two interacted environmental challenges that China's power sector is facing. We investigate long-term transition pathways (2020–2050) of China's power sector under carbon neutrality target and water withdrawal constraint using an integrated capacity expansion and dispatch model: SWITCH-China. We find that achieving carbon neutrality before 2060 under moderate cost decline of renewables by 10–20% depends heavily on large scale deployment of coal-fired power generation with carbon capture and storage (CCS) since 2035 in China's water-deficient northwestern regions, which may incur significant water penalties in arid catchments. Introducing water withdrawal constraints at the secondary river basin level can reduce the reliance on coal-CCS power generation to achieve carbon neutrality, promote the application of air-cooling technology, and reallocate newly built coal power capacities from northwestern regions to northeastern and southern regions. If levelized cost of renewables can decline rapidly by about 70%, demand for coal power generation with CCS will be significantly reduced by more than 80% and solar photovoltaic (PV) and wind could account for about 70% of the national total power generation by 2050. The transition pathway under low-cost renewables also creates water conservation co-benefits of around 10 billion m³ annually compared to the reference scenario.
... Hence, raising the share of RES into the grid can be rather challenging-especially in terms of production and demand mismatches, as well as stability of supply [17][18][19][20][21]. Consequently, the role of energy storage in boosting the deployment of renewables is vital [22][23][24][25]. However, energy storage can have a strong influence on the costs of solar and wind electricity, in their effort to meet energy demand in high RES penetration scenarios [26][27][28]. As it is related to the intermittent operation of power plants, the incurrence of such additional costs should not be neglected [29,30]. ...
Article
Full-text available
Raising the penetration of renewable energy sources constitutes one of the main pillars of contemporary decarbonization strategies. Within this context, further progress is required towards the optimal exploitation of their potential, especially in terms of dispatchability, where the role of storage is considered vital. Although current literature delves into either storage per se or the integration of storage solutions in single renewable technologies, the comparative advantages of each technology remain underexplored. However, high-penetration solutions of renewable energy sources (RES) are expected to combine different technological options. Therefore, the conditions under which each technology outperforms their counterparts need to be thoroughly investigated, especially in cases where storage components are included. This paper aims to deal with this gap, by means of assessing the combination of three competing technologies, namely concentrated solar power (CSP), photovoltaics (PV) and offshore wind, with the storage component. The techno-economic assessment is based on two metrics; the levelized cost of electricity and the net present value. Considering the competition between the technologies and the impact storage may have, the paper’s scope lies in investigating the circumstances, under which CSP could have an advantage against comparable technologies. Overall, PVs combined with storage prevail, as the most feasible technological option in the examined storage scenarios—with an LCOE lower than 0.11 €/kWh. CSP LCOE ranged between 0.1327–0.1513 €/kWh for high capacity factors and investment costs, thus larger storage components. Offshore wind—with a lower storage component—had an LCOE of 0.1402 €/kWh. Thus, CSP presents the potential to outperform offshore wind in cases where the latter technology is coupled with high storage requirements. CSP can be viewed as one of the options that could support European Union (EU) decarbonization scenarios. As such, an appropriate market design that takes into consideration and values CSP characteristics, namely dispatchability, is needed at the EU level.
... Reports show that demand response could improve load following capability of the power systems [2][3][4]. Energy storage also has the potential to improve grid flexibility and increase grid penetration of variable renewable energy resources while curtailment was reported to lead to high penetration at reduced storage and conventional balancing resources [1,[5][6][7][8][9][10][11][12][13][14][15][16][17][18][19][20][21][22][23]. In a recent study, the link between curtailment, penetration and storage need was reported to play a significant role in system design during energy transition [24]. ...
Article
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Resource complementarity carries significant benefit to the power grid due to its smoothing effect on variable renewable resource output. In this paper, we analyse literature data to understand the role of wind-solar complementarity in future energy systems by evaluating its impact on variable renewable energy penetration, corresponding curtailment, energy storage requirement and system reliability. Results show that wind-solar complementarity significantly increases grid penetration compared to stand-alone wind/solar systems without the need of energy storage. However, as capacity increases, the capability of complementarity to increase grid penetration approaches its limit due to the reduced matching of output to the load profile and pursuant increase in excess generation. Thus, achieving very high penetration requires appropriately designed energy storage and curtailment. Yet, even at higher grid penetration, complementarity carries significant multidimensional benefits to the power system. The most important observation was the achievement of very high grid penetration at reduced energy storage and balancing requirements compared to stand-alone systems. Researchers reported that using the same energy storage capacity, wind-solar complementarity led to significantly higher penetration of up to 20% of annual demand compared to stand-alone systems. In addition, by coupling to curtailment as an enabler, and related dispatch flexibility that comes with storage application, lower balancing capacity need was reported at higher penetration. Wind-solar complementarity was also found to reduce ramping need while contributing to improved system adequacy. Complementarity from other dispatchable renewable resources further reduces storage need and curtailment and improve system reliability, whereas power grid integration and relative cost changes allow for further optimisation while transitioning to 100% renewable energy.
... Pietzcker et al. [19] have used the REMIND model to propose that solar power might dominate the global electricity mix by Year 2100. Mileva et al. [20] have also demonstrated, using the SWITCH model, that solar power can cost-effectively cover over a third of the electricity demand in the Western US electricity system by Year 2050, assuming that the US Department of Energy's cost target of $1 per W p for solar PVs is reached. However, these studies do not take into account the household perspective, which could significantly affect the diffusion of PV technologies. ...
Article
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The profitability of investments in photovoltaics (PVs) and batteries in private households depends on the market price of electricity, which in turn is affected by the investments made in and the usage of PVs and batteries. This creates a feedback mechanism between the centralised electricity generation system, and household investments in PVs and batteries. To investigate this feedback effect, we connect a local optimisation model for household investments with a European power generation dispatch model. The local optimisation is based on the consumption profiles measured for 2104 Swedish households. The modelling compares three different scenarios for the centralised electricity supply system in Year 2032, as well as several sensitivity cases. Our results show total investment levels of 5–20 GWp of PV and 0.01–10 GW h of battery storage capacity in Swedish households in the investigated cases. These levels are up to 33% lower than before market feedback is taken into account. The profitability of PV investments is affected most by the price of electricity and the assumptions made regarding grid tariffs and taxes. The value of investments in batteries depends on both the benefits of increased self-consumption of PV electricity and market arbitrage.
... The model incorporates a combination of current and advanced grid assets. Optimization is subject to reliability, constraints on operations, and resource availability, as well as on current and potential climate policies and environmental regulations [17][18][19][20][21] . ...
Article
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The costs for solar photovoltaics, wind, and battery storage have dropped markedly since 2010, however, many recent studies and reports around the world have not adequately captured such dramatic decrease. Those costs are projected to decline further in the near future, bringing new prospects for the widespread penetration of renewables and extensive power-sector decarbonization that previous policy discussions did not fully consider. Here we show if cost trends for renewables continue, 62% of China’s electricity could come from non-fossil sources by 2030 at a cost that is 11% lower than achieved through a business-as-usual approach. Further, China’s power sector could cut half of its 2015 carbon emissions at a cost about 6% lower compared to business-as-usual conditions.
... Electricity systems that rely on large amounts of solar power benefit from storage between day and night, day and the next morning, as well as from support during cloudy days and some seasonal variations. Mileva et al [13] show that high levels of solar generation in the electricity system can be cost-effectively integrated using a portfolio of technological options. Göransson and Johnsson [14] have shown that batteries are typically the preferred option for intra-day storage that spans over a couple of hours, while wind power generation needs storage for longer periods of variation [14]. ...
Article
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The increasing levels of variable renewable electricity (VRE) generation-such as wind and solar power-will create important opportunities for the charging of electric vehicle (EV) batteries during low-cost hours with a lot of VRE generation and for the discharge of EV batteries back to the grid (i.e. vehicle-to-grid; V2G) during high-cost hours. This study investigates how different EV charging strategies influence the cost-competitiveness of generation and storage technologies other than EV batteries in the electricity system, using a regional electricity system investment and dispatch model. The charging requirements of the EVs, which are used as an input to the optimisation model, are derived from the yearly driving patterns of 426 vehicles measured with global positioning system. The study is carried out for four regions in Europe with different conditions for wind, solar and hydro power generation. The results show that optimised EV charging with V2G can: (i) reduce investments in peak power capacity in all the regions investigated; (ii) reduce the need for short-term and long-term storage technologies other than EV batteries (i.e. stationary batteries and hydrogen storage); and (iii) stimulate increased shares of solar and wind power generation, as compared to direct charging in some regions (mainly Hungary). This study also shows that EV battery capacities as low as 30 kWh, which are connected to the grid only at their home location, can to a large extent contribute with flexibility to the electricity system in the way mentioned. The present study also investigates the influences of different shares of the fleet participating in V2G, and shows that the additional benefits for the electricity system level off when approximately 24% of the vehicle fleet participates in V2G.
... [1][2][3] In some prospective analyses, these costs continue to fall to levels where the levelized cost of wind and solar electricity drops below higher-carbon alternatives. 4 However, to allow intermittent wind and solar generation to meet demand, back-up generation, energy storage, expanded transmission infrastructure, demand-side management, and energy curtailment may be required, [5][6][7][8][9][10][11] affecting the total costs of supplying solar and wind electricity. These costs are important to account for, as are the costs incurred by operating any type of power plant intermittently. ...
Article
Deeply decarbonizing electricity production will likely require that low-carbon sources meet energy demand throughout days, years, and decades. Wind and solar energy are possible low-carbon options, but resource variability can limit their reliability. Storage can help address this challenge by shaping intermittent resources into desired output profiles. But can solar and wind energy with storage cost-competitively fulfill this role? How do diverse storage technologies compare? We address these questions by analyzing systems that combine wind and solar energy with storage to meet various demand profiles. We estimate that energy storage capacity costs below a roughly $20/kWh target would allow a wind-solar mix to provide cost-competitive baseload electricity in resource-abundant locations such as Texas and Arizona. Relaxing reliability constraints by allowing for a few percent of downtime hours raises storage cost targets considerably, but would require supplemental technologies. Finally, we discuss storage technologies that could reach the estimated cost targets.
... Furthermore, techno-economic feasibility of low-carbon energy system is widely reported by several researcher's for various parts of the world, e.g. Israel [13], Macedonia [14], India [15] , Australia [16], Finland [17], Northeast Asia [18], Portugal [19], Denmark [20], United States [21], global [22], western electricity coordinating council [23], Turkey [24], Saudi Arabia [25], etcetera. Currently, many agree that a RE future is a possibility both technically and economically [26]. ...
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The nexus between growing shares of renewables (penetration), storage requirements, and curtailment was studied using a linear optimisation model. The study was performed using a dataset of Israel’s electricity system. Five scenarios are designed to assess the techno-economic impact of curtailment under various policy-based frameworks. The results show that the three parameters are linked to each other in a way that necessitates simultaneous increase of a total loss (curtailment plus storage efficiency), penetration and storage capacity in the energy transition. Depending on the curtailment policy, penetration increases significantly with a small increase in storage capacity until it reaches a corresponding point of inflection. Based on these physical relationships, storage technologies were classified as diurnal and seasonal. Diurnal storage capacity continually increases to a maximum capacity of about daily average demand, which corresponds to a penetration of approximately 90% of annual demand where the deployment of seasonal storage significantly increases. Having no curtailment was shown to lead to higher total system cost as compared to the system optimised with curtailment. Overall, the nexus between the three factors was shown to define when to deploy and dispatch storage technologies. The evidence supporting these findings is detailed for the first time.
... Switch 1.0 and 2.0 have been used by researchers at several universities and nonprofits to analyze the evolution of power systems in many regions and countries. These include the Western Electrical Coordinating Council (western portion of the United States and Canada with part of Mexico), Chile, Hawaii, Mexico, China, Nicaragua, Japan, Kenya, East Africa, and Peru [2,32,33,[57][58][59][60][61]. ...
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This paper describes Switch 2.0, an open-source modeling platform for planning transitions to low-emission electric power grids, designed to satisfy 21st century grid planning requirements. Switch is capable of long-, medium- and short-term planning of investments and operations with conventional or smart grids, integrating large shares of renewable power, storage and/or demand response. Applications include integrated resource planning, investment planning, economic and policy analyses as well as basic research. Potential users include researchers, educators, industry and regulators. Switch formulates generation and transmission capacity planning as a mixed integer linear program where investment and operation are co-optimized across sampled time series during multiple investment periods. High-resolution production cost modeling is supported by freezing investment decisions and including longer time series and more operational details. Modeling features include unit commitment, part-load efficiency, planning and operating reserves, fuel supply curves, storage, hydroelectric networks, policy constraints and demand response. Switch has a modular architecture that allows users to flexibly compose models by choosing built-in modules 'a la carte' or writing custom modules. This paper describes the software architecture and model formulation of Switch 2.0 and provides a case study in which the model was used to identify the best options for obtaining load-shifting and reserve services from batteries and demand response in a 100% renewable power system.
... Another linear optimization model, REMix, including storage, transmission and generation investments over all of Europe, shows that the environmental impacts (using LCA) of a high renewable penetration scenario are significantly lower in almost all indicators (compared to fossil fuels with carbon capture and storage (CCS), for example) except notably in mineral depletion [3]. In the U.S., the SWITCH model, also a linear economic optimization model, with scenarios focused on reduction in costs in solar technologies [4], demonstrates that very high penetrations of solar PV (accounting for more than a third of electricity by 2050) would likely occur to Chalmers PP Db, together with an extensive array of new and existing technologies that are to be used to meet the changes in future demand as existing capacity comes of age or becomes unprofitable. Both conventional fossil fuel and CCS technologies are available for investment, as well as a portfolio of renewable technologies. ...
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The European roadmap for the power sector dictates an 80–95% cut of existing levels of carbon dioxide emissions is needed by the year 2050 to meet climate goals. This article describes results from a linear cost optimization investment model, ELIN, coupled with a solar technology model, Distributed Concentrating Solar Combined Heat and Power (DCS-CHP), using published investment costs for a comprehensive suite of renewable and conventional electricity generation technologies, to compare possible scenarios for the future electricity grid. The results of these model runs and sensitivity analyses indicate that: (1) solar photovoltaics (PV) with battery storage will likely play a very large role in meeting European targets; (2) concentrating solar power (CSP) with thermal energy storage is at a slight economic disadvantage with respect to PV to compete economically; (3) the economic potential of wind power is only comparable with solar PV if high wind penetration levels are allowed in the best wind sites in Europe; and (4) carbon capture and nuclear technologies are unlikely to compete economically with renewable technologies in creating a low-carbon future grid.
... I n the face of the Paris climate agreement 1 , a combined transition to clean energy and acceleration of decarbonization goals will require the refocusing of US and international research and deployment schemes to promote energy R&D [2][3][4] . Dramatic cost declines in solar and wind technologies, and now energy storage, open the door to a reconceptualization of the roles of research and deployment of electricity production, transmission, and consumption that enable a clean energy transition 5,6 . While basic research remains a vital element to address a clean energy transition, increasingly an interdisciplinary approach is needed. ...
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... Reports show that demand response could improve load following capability of the power systems [2][3][4]. Energy storage also has the potential to improve grid flexibility and increase grid penetration of variable renewable energy resources while curtailment was reported to lead to high penetration at reduced storage and conventional balancing resources [1,[5][6][7][8][9][10][11][12][13][14][15][16][17][18][19][20][21][22][23]. In a recent study, the link between curtailment, penetration and storage need was reported to play a significant role in system design during energy transition [24]. ...
Conference Paper
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Resource complementarities carry significant benefit to the power grid due to their smoothing effect on the variable renewable resources output. In this paper, we show that complementarity significantly reduces energy storage requirement by using simulation results generated for Israel, Saudi Arabia, California and Finland. In a complementarity study performed using Israeli and Californian data sets (focusing on the electricity sector alone), the wind-solar complementarities were shown to significantly increase grid penetration as compared to stand-alone wind/solar systems even without the need of energy storage. At even higher grid penetration their complementarity carries significant multidimensional benefits to the power grid. The most important observation was the achievement of very high grid penetration at reduced energy storage and balancing requirements as compared to stand-alone systems. Using specific energy storage capacity (186 GWh/22 GW) and setting the solar share to 0%, 50% and 100% of the total VRE capacity, the 50-50 wind-solar capacity mix has led to significantly higher penetration as compared to the stand-alone systems. For instance, by allowing 15% energy curtailment, it was shown that grid penetration of 63%, 80% and 55% of the annual demand, respectively, can be achieved. This was because of storage being able to follow a flexible dispatch strategy, which makes it applicable for various services depending on the season of the year and the available resources. A study on a 100% renewable energy system of Finland shows that one of the best scenarios was related to a 43%-57% wind-solar capacity mix for a 70% VRE penetration by 2050. A similar study on Saudi Arabia shows that broader resource complementarity and higher level of flexibility obtained through sector coupling has reduced the required storage very significantly. The results indicate that the multiple benefits obtained from resource complementarity should be emphasized during the transition to systems of high renewable energy shares.
... It is also emphasized that the reserve requirement increases with an increase in intermittent renewable, which may lead to larger generation system capacity and higher cost of electricity [19][20][21]43]. Corresponding increase in storage need (observed as renewable capacity increase) was also reported [18][19][20][21][22]. Such an increase in reserve capacity need could be reduced if we create the ability to value/emphasize energy storage role in providing the required reserve. ...
... As intermittent renewable generation achieves higher penetration levels, integration alternatives such as transmission expansion, fast-ramping generation, storage, and demand response ought to be considered and compared in a single framework. We have incorporated operational detail into the SWITCH long-term capacity-planning model to allow for more accurate economic evaluation of intermittent renewables, storage technologies, and other integration alternatives [14,15]. Wind and solar generation technologies have low variable costs but require investment in capital-intensive infrastructure capacity, so employing capacity-expansion models can aid understanding of and planning for the most cost-effective resource combinations as the power system evolves 2. Methods ...
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We explore the operations, balancing requirements, and costs of the Western Electricity Coordinating Council power system under a stringent greenhouse gas emission reduction target. We include sensitivities for technology costs and availability, fuel prices and emissions, and demand profile. Meeting an emissions target of 85% below 1990 levels is feasible across a range of assumptions, but the cost of achieving the goal and the technology mix are uncertain. Deployment of solar photovoltaics is the main driver of storage deployment: the diurnal periodicity of solar energy availability results in opportunities for daily arbitrage that storage technologies with several hours of duration are well suited to provide. Wind output exhibits seasonal variations and requires storage with a large energy subcomponent to avoid curtailment. The combination of low-cost solar technology and advanced battery technology can provide substantial savings through 2050, greatly mitigating the cost of climate change mitigation. Policy goals for storage deployment should be based on the function storage will play on the grid and therefore incorporate both the power rating and duration of the storage system. These goals should be set as part of overall portfolio development, as system flexibility needs will vary with the grid mix.
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Solar and wind power are now cheaper than fossil fuels but are intermittent. The extra supply-side variability implies growing benefits of using real-time retail pricing (RTP). We evaluate the potential gains of RTP using a model that jointly solves investment, supply, storage, and demand to obtain a chronologically detailed dynamic equilibrium for the island of Oahu, Hawai‘i. We find that, holding demand assumptions fixed, RTP reduces costs in high-renewable systems by roughly 6 to 12 times as much as in fossil systems, markedly lowering the cost of clean energy integration. (JEL G31, L94, L98, Q42, Q48)
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Long-Duration Energy Storage (LDES) has gained interest due to its key role in attaining a decarbonized, low-cost, and stable grid driven by variable renewable electricity (VRE). Currently, there is a wide range of LDES technologies being developed to provide electricity with 8+ hours of consecutive discharge. However, current capacity expansion models used in long-term planning processes rarely consider low cost LDES as a candidate technology. If they do, the storage balancing horizon (SBH) of the model usually only considers non-consecutive 1-day periods that do not capture the potential of LDES to shift energy across multiple days or even seasons. Addressing these limitations in existing models, this work explores the ways in which the optimal energy storage changes when increasing the number of consecutive days in the SBH and how these changes will impact planners who are determining the future roles of energy storage. Our analysis uses SWITCH, an open-source capacity expansion model with a high spatial resolution for the entire Western Electricity Coordinating Council (WECC) in a zero-carbon scenario in 2050. We find that the number of consecutive days in the SBH changes both the total selected power and energy capacity of LDES when storage energy and power capacity overnight costs are $13 USD/kWh (or less) and $113 USD/kW, respectively. We also find that the amount of required energy in storage to drive a future VRE-driven WECC grid ranges from 2.5 TWh to 16.0 TWh depending on the length of the SBH. The optimal storage duration (energy to power ratio) we obtain ranges from 10 h to 620 h among all the scenarios. Furthermore, depending on the storage cost assumption, we observe different charge/discharge patterns when varying the length of the SBH. Given our results, we anticipate that as more LDES technologies become commercially available, it will be critical to increase the length of the SBH to fully capture the benefits of LDES assets in long-term planning processes of high VRE-driven grids.
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The potential contributions of this critical review are to provide a detailed complement of the status, barriers, and prospect of the supercritical carbon dioxide (S-CO2) cycle power technology, and give a clue to promote its application. The state-of-the-art and existing problems of the S-CO2 power technology are reviewed from the perspective of system analysis and component design. The emphasis is put on the application in next-generation high-temperature solar thermal power plants, next-generation compact nuclear reactor power plants, and coal-fired power plants to reveal the thermodynamic, economic, environmental, and flexible feasibility. The construction of the S-CO2 demonstration power station developed in recent years is also summarized to provide a comprehensive understanding of the development route. Finally, the potential of the S-CO2 cycle to establish a multi-generation system is proposed with a promising peak-shaving ability. Meanwhile, advice is stated to facilitate the further growth of this novel power conversion technology. This study is expected to help understand the recent development progress in S-CO2 power technology.
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In this study, a stochastic multistage lifecycle programming model (SMLP) for supporting the management of power systems and the associated economic and environmental risks is proposed. A two-fold objective is pursued. First, information on lifecycle GHG emissions from 10 forms of power generation technologies is comprehensively reviewed and characterized. Second, optimized pathways for the electricity system transition with specific consideration of lifecycle GHG emissions and lifecycle costs are identified. This work presents methodological advances in integrating the lifecycle concept with a power system optimization model, which can enhance the robustness of the resulting decision support. A case study for the Province of Saskatchewan is undertaken, where various uncertainties and risks are quantified and trade-offs among a number of system objectives/criteria are analyzed. According to the review, the lowest average emission per unit power generation is hydropower (12.8 g CO2-eq/kWh), closely followed by offshore wind power (14.6 g CO2-eq/kWh) and on-shore wind power (15.3 g CO2-eq/kWh). According to the modeling results, on-shore wind power is likely to become the dominant form of power generation in Saskatchewan by the end of the planning horizon; import power would play a big part in securing the province's electricity supply in the future. It is expected that the modeling results can help support the formulation of regional energy and relevant socio-economic and environmental policies.
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The article presents various aspects of harnessing solar energy and green hydrogen which is one of the objectives of the EU and Poland’s energy transition. Theoretical issues were examined on the basis of the analysis of available source literature on renewable energy sources (RES), green hydrogen and energy transition. The research methods used in this paper include: critical analysis of the source literature, comparative analysis method and secondary data analysis. The article describes actions taken in Poland to facilitate the energy transition associated with harnessing solar energy and green hydrogen and presents author’s diagram of energy transition related to RES and green hydrogen in EU and Poland. The analysis and assessment carried out in the article indicated that the new concept of operation of the entire energy market and its transition involves the integration of three sectors: transport, heat engineering and power engineering. In the future, green hydrogen will enable a reduction of CO2 emissions from the power engineering and heat engineering sector to zero. Importantly, the electrification of heat engineering and transport based on domestic renewable energy sources will render Poland independent of the energy resources from other countries. The issues as presented in the article concerning renewable energy sources, green hydrogen and energy transition have not been collectively studied in Polish and foreign literature.
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We study the cost and lock in of carbon intensive technologies due to weak medium-term policies. We use SWITCH WECC—a power system capacity expansion optimization model with high temporal and geographical resolution. We test three carbon cap scenarios. For each scenario, we optimize the power system for a medium timeframe (2030) and a long timeframe (2050). In the medium timeframe optimizations, by 2030 coal replaces gas power. This occurs because the long optimization foresees the stronger carbon cap in 2050. Therefore, it is optimal to transition towards cleaner technologies as early as 2030. The medium-term optimization has higher costs in 2040 and 2050 compared to the long optimization. Therefore, to minimize total costs to reduce emissions by 80 % in 2050, we should optimize until 2050 or have stronger carbon cap policies by 2030 (such as 26 % carbon emissions reductions from 1990 levels by 2030 across the WECC).
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The research team developed several long-term energy scenarios for California that detail how the state can meet its aggressive climate targets for 2030 and 2050 (40 percent and 80 percent greenhouse gas reduction from 1990 levels, respectively)
Article
The concentrating solar power (CSP) technology is promising especially for countries having an abundance of solar resources in order to secure their energy supply, reduce their carbon footprint and consequently achieve sustainable development goals. Furthermore, the thermal energy storage (TES), when combined with CSP plants, offers the opportunity to make these plants economically competitive and reliable during their operation and could balance supply and demand of energy by reducing the undesirable impacts of the solar energy intermittency. This paper presents a review on TES systems and an update of the latest developments of different technologies of TES that are commercially available or under investigation. Various aspects are discussed including the limits of each technology, different new concepts to enhance the heat transfer efficiency, the principal applications and the environmental issues associated with the integration of TES in solar thermal CSP plants. The results of the current review have revealed that despite the important thermo-physical characteristics of latent heat and thermo-chemical heat storage systems, such as high TES density, they are still at a laboratory level and their development is still far from any proven design and material to be transferred to a commercial scale, especially for high temperature applications. In contrast, the liquid sensible heat storage (SHS) systems are the most mature and the most used in CSP plants. Indeed, according to a census survey that we carried out, based on data compiled by the National Renewable Energy Laboratory (NREL) and Global Energy Observatory (GEO) about CSP projects around the world that are either operational or under development, 45.5% of the operational CSP plants worldwide (i.e. 45.1% of the total installed capacity) are equipped with TES and 95.6% of them (i.e. 99.8% of the total installed capacity) use liquid SHS materials due to their reliability, low cost and easy operation. Economically, the integration of TES systems into large scale CSP plants is a cost-effective way for the widespread deployment of CSP technology, by reducing the levelized cost of electricity (LCOE), especially for solar power tower (SPT) technology over parabolic trough collector (PTC) one, thanks to the high temperature differential occurred in the storage system that reduces the amount of required TES materials. However, owing to its longer commercial operational experience and less technical and financial risks, the PTC is currently the most commonly used technology in CSP plants. Regarding the environmental side, a case study about Moroccan CSP has quantitatively highlighted the environmental potential of integrating TES in CSP plants for electricity production in order to mitigate significantly the greenhouse gases emissions.
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Recent climate initiatives had initiated a wave of reducing CO2 emissions for power generation. Many countries have been striving to develop and deploy low carbon emission technologies for power generation through efficiency improvement and use of renewable energy. For the regions that gain sufficient amount of solar to make solar power attractive overall, the challenge of intermittency still poses an issue for the electricity grid. The complementary role of natural gas power for the incoming renewables will be reinforced in the near future, but emission of CO2 needs to be avoided through means such as carbon capture and storage. A novel solution of integrating the s-CO2 oxy-combustion system with the concentrated solar power (CSP) is devised. The suggested concept will provide direction to satisfy the growing electricity demand, yet with environmental sustainability. The evaluation of this system in several regions possible for CSP installation shows reduction of fuel consumption by 17–38% compared to conventionally separated systems.
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Power systems have evolved following a century-old paradigm of planning and operating a grid based on large central generation plants connected to load centers through a transmission grid and distribution lines with radial flows. This paradigm is being challenged by the development and diffusion of modular generation and storage technologies. We use a novel approach to assess the sequencing and pacing of centralized, distributed, and off-grid electrification strategies by developing and employing the grid and access planning (GAP) model. GAP is a capacity expansion model to jointly assess operation and investment in utility-scale generation, transmission, distribution, and demand-side resources. This paper conceptually studies the investment and operation decisions for a power system with and without distributed resources. Contrary to the current practice, we find hybrid systems that pair grid connections with distributed energy resources (DERs) are the preferred mode of electricity supply for greenfield expansion under conservative reductions in photovoltaic panel (PV) and energy storage prices. We also find that when distributed PV and storage are employed in power system expansion, there are savings of 15%-20% mostly in capital deferment and reduced diesel use. Results show that enhanced financing mechanisms for DER PV and storage could enable 50%-60% of additional deployment and save 15 $/MWh in system costs. These results have important implications to reform current utility business models in developed power systems and to guide the development of electrification strategies in underdeveloped grids.
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The low-carbon transition of power industry plays a vital role in China's energy system revolution. Both policy support and cost reductions have greatly driven the development of renewable energy technologies, especially wind and solar power generation technologies. Considering the cost uncertainty of renewables, we developed a National Energy Technology-Power model to assess the possible low-carbon transition pathways for six regional power industries using four renewable energy cost change scenarios. Resource endowments and technology developments trends were also considered to achieve an effective and coordinated utilization of various resources. The results show that declining renewable energy costs have a great impact on the spatial and temporal development of power generation technologies, and on the interregional clean power transmission. If the investment costs of renewable energy technologies continue to decline at a high speed and the renewables could be dramatically developed, the CO 2 emissions of China's power industry is expected to peak at 3.12 GtCO 2 in 2026. Accordingly, the capacity share of renewable energy technologies in regional power industries would exceed 50% except in East China, and the total installed coal-fired technology capacity would fall to 760.2 GW in 2050. In addition, to promote the optimal allocation of resources, the total amounts of interregional clean power transmission are suggested to be 416 TWh in 2035 and 587 TWh in 2050, i.e., 4.9% and 5.5% of the total amount of power generation, respectively. 106 TWh of wind power is expected to be exported from Northwest to Center and East regions in 2050; and 112 TWh of solar power is suggested to be exported from North to Center, East and South regions. The Northwest region is the largest exporter of clean power while the East region is the main importer. These conclusions could support the regional plan of power transmission network.
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Phase change behaviors of organic phase change materials (PCMs) confined in porous silica matrices, which are determined by the pore characteristics as well as interfacial interactions between PCM molecules and supporting solid, are crucial to PCMs for thermal energy storage performance. In this paper, a series of shape-stabilized phase change materials (ss-PCMs) were engineered with three silica matrices as support and paraffin as PCMs through solution impregnation. These porous silica matrices serve as an ideal skeleton for shape stabilization of melted paraffin PCMs and yield desirable thermal properties of paraffin confined in silica pores. The textural and chemical properties, crystallization, interfacial interactions, and thermal properties and stability are investigated using various techniques including nitrogen adsorption-desorption isotherms, Fourier transformation infrared (FT-IR) spectroscopy, small- and wide-angle X-ray diffraction (XRD), and scanning electron microscopy, as well as differential scanning calorimetry (DSC) analysis. The effect of the pore structure on crystallization of PCMs was studied and a novel phase change was unveiled. The phenomena of melting point depression and confinement effects are in line with theoretical thermodynamics, and the physical state of paraffin at the interfacial region in mesopore channel is analyzed considering pore geometric factors, revealing a non-melting interface layer in MCM-41. This evaluation of various silica matrices may provide important and general implications for the fundamental understanding of porous silica ss-PCMs performance with cost-effective and readily available raw materials.
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In the context of recent dramatic solar energy cost reductions, the U.S. Department of Energy set new levelized cost of energy goals for photovoltaics (PV) to achieve by 2030 to enable significantly greater PV adoption: $0.03/kWh for utility-scale, $0.04/kWh for commercial, and $0.05/kWh for residential PV systems. We analyze the potential impacts of achieving these “SunShot 2030” cost targets for the contiguous United States using the Regional Energy Deployment System (ReEDS) and Distributed Generation (dGen) capacity expansion models. We consider the impacts under a wide range of future conditions. We find that PV could provide 13%–18% of U.S. electricity demand in 2030 and 28%–64% of demand if the SunShot 2030 goals are achieved, with PV deployment increasing in every state. The availability of low-cost storage has the largest impact on projected deployment, followed by natural gas prices and electricity demand. For comparison, PV deployed under a business-as-usual scenario could provide only 5% of generation in 2030 and 17% in 2050. We find that the high levels of PV deployment explored here lead to lower electricity prices and system costs, lower carbon dioxide emissions, lower water consumption, increased renewable energy curtailment, and increased storage deployment compared with the business-as-usual scenario.
Chapter
Decarbonization scenarios for California and other Western states of United States to 2030 and 2050 show a number of relatively robust trends, including significant adoption of plug-in electric vehicles and investments in large quantities of renewable wind and solar generation. These two developments in disparate sectors (electricity and transportation) are linked via the use of electricity in the transportation sector. By expanding the existing California TIMES (CA-TIMES) model and including the Western Electricity Coordinating Council (WECC) electricity region into this model, we explore the impact of California’s policies on the Western Electricity Coordinating Council grid. Our analysis shows that a climate target on California only and not on the other states could contribute to the greening of power plants in the Western States, driven by the possibility to export electricity to California. When a carbon target is extended to all regions, the grid of all Western States, as well as the entire energy system of California, there cannot be zero emissions without adopting carbon capture and storage.
Article
Fast growing and emerging economies face the dual challenge of sustainably expanding and improving their energy supply and reliability while at the same time reducing poverty. Critical to such transformation is to provide affordable and sustainable access to electricity. We use the capacity expansion model SWITCH to explore low carbon development pathways for the Kenyan power sector under a set of plausible scenarios for fast growing economies that include uncertainty in load projections, capital costs, operational performance, and technology and environmental policies. In addition to an aggressive and needed expansion of overall supply, the Kenyan power system presents a unique transition from one basal renewable resource – hydropower – to another based on geothermal and wind power for ~90% of total capacity. We find geothermal resource adoption is more sensitive to operational degradation than high capital costs, which suggests an emphasis on ongoing maintenance subsidies rather than upfront capital cost subsidies. We also find that a cost-effective and viable suite of solutions includes availability of storage, diesel engines, and transmission expansion to provide flexibility to enable up to 50% of wind power penetration. In an already low-carbon system, typical externality pricing for CO2 has little to no effect on technology choice. Consequently, a “zero carbon emissions” by 2030 scenario is possible with only moderate levelized cost increases of between $3 to $7/MWh with a number of social and reliability benefits. Our results suggest that fast growing and emerging economies could benefit by incentivizing anticipated strategic transmission expansion. Existing and new diesel and natural gas capacity can play an important role to provide flexibility and meet peak demand in specific hours without a significant increase in carbon emissions, although more research is required for other pollutant’s impacts.
Article
A regional cost-minimizing investment model that accounts for cycling properties (i.e., start-up time, minimum load level, start-up cost and emissions, and part-load costs and emissions) is developed to investigate the impact of thermal plant cycling on the cost-optimal composition of a regional electricity generation system. The model is applied to an electricity system that is rich in wind resources with and without accounting for cycling in two scenarios: one with favorable conditions for flexible bio-based generation (Bio scenario); and one in which base load is favored (Base load scenario) owing to high prices for biomass. Both scenarios are subject to a tight cap on carbon dioxide emissions, limiting the investment options to technologies that have low or no carbon emissions. We report that in the Bio scenario, the cost-optimal system is dominated by wind power and flexible bio-based generation, whereas base-load generation dominates the Base load scenario, in line with the assumptions made, and the level of wind power is reduced. In the Base load scenario, 19% of the capacity is cycling-dependent, i.e., for this share of installed capacity, the choice of technology is different if cycling properties are included, compared to a case in which they are omitted. In the Bio scenario, in which flexible bio-based generation is less costly, 9% of the capacity is cycling-dependent. We conclude that it is critical to include cycling properties in investment modeling, to assess investments in thermal generation technologies that compete at utilization times in the range of 2000–5000 h.
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Concentrating solar power (CSP) offers the value proposition of being a baseload and dispatchable renewable energy technology. CSP significantly lags behind solar photovoltaic (PV) and wind power by cumulative capacity and cost for a number of reasons including the complicated nature of the technology and the traditional inability of the technology to be economically viable at smaller scales. The scaling limitation itself has prevented the technology from learning faster due to limited market share, which has inhibited the learning rate and continued to make CSP project financing difficult due to finance quantum risks. CSP has limited but successful lifecycle experience due to the SEGS I–IX plants commissioned between 1985 and 1990 in California. More recently, the technology benefited from competitive tariffs before the adoption of PV and learning rates undermined its growth. PV (as with wind) now offers some of the lowest electricity generating rates of any technology. While this is valuable, the marginal value of intermittent renewables is roughly inversely proportional to their share of the electricity system as their capacity credit diminishes with each addition to capacity, all other things equal. CSP with storage has the ability to flexibly deliver electricity and to do so 24 h a day in the right conditions. CSP plants with up to 15 h of full-load storage have now been commissioned and are demonstrating initial evidence that they can deliver to expectation. Despite the proposed value of CSP, it is not penetrating the market as expected. The value of electricity has simply not been valued for instance in the U.S. market to date, which has valued renewable targets above capacity needs. Sunny developing countries have been identified as potential growth markets due to capacity constraints and the avoided cost of electricity. Most recently, China has embarked on the greatest capacity growth of CSP in the decision to commission around 5 GW of CSP within the next 5 years with 1.35 GW assigned to be online by the end of 2018. Even with this evolution, CSP will still significantly lag other renewables. This review covers the system value and progress of CSP. An overall description of CSP and its value is followed by a broad review of CSP experience and research. A review of CSP in energy systems analysis is then provided to expose and quantify the marginal value of CSP. It is argued that improved quantification and accuracy in terms of energy systems analysis is an important step for CSP growth. The findings from the review show that CSP has potential to be the backbone of future electricity systems, but it needs to demonstrate value and acceptance to a broader audience than might be expected to achieve this.
Conference Paper
Planning the long-term expansion of a power sector requires anticipating future technologies, fuel costs, and new carbon policies. Many state-of-the-art models rely on exogenous data for cost and performance projections where the inherent uncertainty is either ignored or addressed only with sensitivity analysis and scenarios. For the few models accounting for uncertainty, the transition from the research field to policy making has not occurred because of important practical barriers in the latter field: higher reliance on time-tested models, impossibility to constantly adopt new models, run-time issues. To streamline this process, we present a new modular two-step methodology, based on mean-variance optimization, to help policy makers adjust for risks on costs their findings from current cost-minimizing tools, while sparing them the hurdles of adopting a new model. To illustrate this, we refine the SWITCH-China least-cost power expansion pathway by minimizing its cost uncertainty.
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Despite impressive declines in average prices, there is wide dispersion in the prices of U.S. solar photovoltaic (PV) systems; prices span more than a factor of four. What are the characteristics of the systems with low-prices? Using detailed characteristics of 42,611 small-scale (<15 kW) PV systems installed in 15 U.S. states during 2013, we identify the most important factors that make a system likely to be low-priced (LP). Comparing LP and non-LP systems, we find statistically significant differences in nearly all characteristics for which we have data. Logit and probit model results robustly indicate that LP systems are associated with: markets with few active installers; experienced installers; customer ownership; large systems; retrofits; and thin-film, low-efficiency, and Chinese modules. We also find significant differences across states, with LP systems much more likely to occur in some states, such as Arizona, New Jersey, and New Mexico, and less likely in others, such as California. Our focus on the left tail of the price distribution provides implications for policy that are distinct from recent studies of mean prices. While those studies find that PV subsidies increase mean prices, we find that subsidies also generate LP systems. PV subsidies appear to simultaneously shift and broaden the price distribution. Much of this broadening occurs in a particular location, northern California.
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Solar thermal fuel is a promising approach of solar energy utilization, in which concentrating solar energy can drive the hydrocarbon fuel decomposition or steam reforming to produce hydrogen or syngas for generating power through heat engine. In the present, most of solar thermal fuel processes have employed solar heat at above 800 °C which needs higher-concentration-ratio solar cavity reactor with higher re-radiation loss, bringing about poor annually average efficiency of solar-fuel-power. Here, a mid-temperature solar thermal fuel system by using chemical looping combustion (CLC) is studied for producing cooling, heating and power. The concentrated solar heat at approximately 350 °C is utilized to drive the dimethyl ether fueled-chemical looping combustion with pair of CoO/Co as oxygen carrier. By using the mid-temperature solar heat driving CLC, the low-grade solar heat is upgraded into high-grade chemical energy of metal Co as solar fuel that is further converted into high-temperature thermal energy at 900 °C via oxidation of Co and drives a recuperated gas turbine for generating power. The waste heat from the gas turbine can be utilized to produce a double-effect water/lithium bromide absorption chiller for producing the cooling and the heating. The thermodynamic performance of this mid-temperature solar fuel system is analyzed and the effects of several operation parameters such as solar irradiation, production of the solar fuel and pressure ratio are examined. The annually average efficiency of solar-fuel-power can be about 21%, with approximately 5 percentage points higher than that of solar thermal power system. In addition, the reason of the improvement in the performance is revealed by the irreversibility methodology. Our results would be expected to bring a new pathway for the application of solar thermal fuel in the distributed CCHP technology.
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We present an integrated model, SWITCH-China, of the Chinese power sector which we use to analyze the economic and technological implications of a medium to long-term decarbonization scenario while accounting for very short-term renewable variability. Based on the model and assumptions used, we find that the announced 2030 carbon peak can be achieved with a carbon price of ~$40/tCO2. Current trends in renewable energy price reductions alone are insufficient to replace coal, however, an 80% carbon emission reduction by 2050 is achievable in the IPCC Target Scenario with an optimal electricity mix in 2050 including nuclear (14%), wind (23%), solar (27%), hydro (6%), gas (1%), coal (3%), CCS coal (26%). The co-benefits of carbon-price strategy would offset 22% to 42% of the increased electricity costs if the true cost of coal and social cost of carbon are incorporated. In such a scenario, aggressive attention to research and both technological and financial innovation mechanisms are crucial to enabling the transition at reasonable cost, along with strong carbon policies.
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Significance The large-scale conversion to 100% wind, water, and solar (WWS) power for all purposes (electricity, transportation, heating/cooling, and industry) is currently inhibited by a fear of grid instability and high cost due to the variability and uncertainty of wind and solar. This paper couples numerical simulation of time- and space-dependent weather with simulation of time-dependent power demand, storage, and demand response to provide low-cost solutions to the grid reliability problem with 100% penetration of WWS across all energy sectors in the continental United States between 2050 and 2055. Solutions are obtained without higher-cost stationary battery storage by prioritizing storage of heat in soil and water; cold in water and ice; and electricity in phase-change materials, pumped hydro, hydropower, and hydrogen.
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Photovoltaics is a solar power technology to generate Electricity using semiconductor devices, known as solar cells. A number of solar cells form a solar "Module" or "Panel", which can then be combined to solar systems, ranging from a few Watts of electricity output to multi Megawatt power stations. The unique format of the Photovoltaic Status Report combines international up-to-date information about Research Activities with Manufacturing and Market Implementation data of Photovoltaics. These data are collected on a regular basis from public and commercial studies and cross-checked with personal communications. Regular factfinding missions with company visits, as well as meetings with officials from funding organisations and policy makers, complete the picture. Growth in the solar Photovoltaic sector has been robust. Yearly growth rates over the last decade were on average more than 40 %, thus making Photovoltaics one of the fastest growing industries at present. The PV Status Report provides comprehensive and relevant information on this dynamic sector for the public interested, as well as decision-makers in policy and industry.
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The Eleventh Edition of the “PV Status Report” tries to give an overview about the current activities regarding Research, Manufacturing and Market Implementation. Over the last fifteen years, the photovoltaic industry has grown from a small group of companies and key players, into a global business where information gathering is getting more and more complex. Not every country and development is treated with the same attention, but this would go beyond the scope of this report. Any additional information would be highly welcome and will be used for the update of the report.
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Meeting a greenhouse gas (GHG) reduction target of 80% below 1990 levels in the year 2050 requires detailed long-term planning due to complexity, inertia, and path dependency in the energy system. A detailed investigation of supply and demand alternatives is conducted to assess requirements for future California energy systems that can meet the 2050 GHG target. Two components are developed here that build novel analytic capacity and extend previous studies: (1) detailed bottom-up projections of energy demand across the building, industry and transportation sectors; and (2) a high-resolution variable renewable resource capacity planning model (SWITCH) that minimizes the cost of electricity while meeting GHG policy goals in the 2050 timeframe. Multiple pathways exist to a low-GHG future, all involving increased efficiency, electrification, and a dramatic shift from fossil fuels to low-GHG energy. The electricity system is found to have a diverse, cost-effective set of options that meet aggressive GHG reduction targets. This conclusion holds even with increased demand from transportation and heating, but the optimal levels of wind and solar deployment depend on the temporal characteristics of the resulting load profile. Long-term policy support is found to be a key missing element for the successful attainment of the 2050 GHG target in California.
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Wind and solar power are highly variable, so it is it unclear how large a role they can play in future power systems. This work introduces a new open-source electricity planning model--Switch--that identifies the least-cost strategy for using renewable and conventional generators and transmission in a large power system over a multidecade period. Switch includes an unprecedented amount of spatial and temporal detail, making it possible to address a new type of question about the optimal design and operation of power systems with large amounts of renewable power. A case study of California for 2012-2027 finds that there is no maximum possible penetration of wind and solar power--these resources could potentially be used to reduce emissions 90% or more below 1990 levels without reducing reliability or severely raising the cost of electricity. This work also finds that policies that encourage customers to shift electricity demand to times when renewable power is most abundant (e.g., well-timed charging of electric vehicles) could make it possible to achieve radical emission reductions at moderate costs.
Conference Paper
As photovoltaic (PV) penetration is gaining its momentum in the recent past, grid codes will demand contribution by PV systems to frequency regulation. This paper presents an investigation into the frequency regulation aspect of photovoltaic systems. An inertial response from photovoltaic system is derived by making it to work away from MPPT point of operation. The case of frequency response under deloaded operation with frequency regulation is compared with the case when the photovoltaics are not contributing to frequency regulation. A microgrid with a conventional synchronous machine and six photovoltaic generators in a distributed scenario is considered for the study.
Conference Paper
Grid integration of wind power plants is complicated by a number of issues, primarily related to wind variability and the electrical characteristics of wind generators. Frequency control is a particularly significant issue with high levels of wind and solar penetration. A typical wind plant appears to the grid as a substantially different generation source than a conventional power plant. A significant difference is that the wind energy source is inherently uncontrollable. In addition, the electrical characteristics of wind generators result in a disturbance response that is naturally different from that of conventional synchronous generators. Without special controls, a wind plant does not inherently participate in the regulation of grid frequency as do synchronous machines. And, when wind generation displaces conventional synchronous generation, the burden of frequency regulation placed upon the remaining synchronous generators is increased. The paper summarizes results from a recent investigation of system frequency response in the Western US as it may be affected by large amounts of wind generation. Impacts and benefits of wind plant controls that provide frequency response are illustrated with quantitative examples. Both inertial and primary frequency response behaviors are examined.
Article
In electrical islands, frequency excursions are sizeable and automatic load shedding is often required in response to disturbances. Moreover, the displacement of conventional generation with wind and solar plants, which usually do not provide inertial response, further weakens these power systems. Fast-acting storage, by injecting power within instants after the loss of a generating unit, can back up conventional generation assets during the activation of their primary reserve. This paper relies on dynamic simulations to study the provision of such a dynamic frequency control support by energy storage systems in the French island of Guadeloupe with large shares of wind or solar generation. The results show that fast-acting storage, by acting as a synthetic inertia, can mitigate the impact of these sources on the dynamic performance of the studied island grid in the case of a major generation outage. The other concerns raised by renewables (e.g., variability, forecast accuracy, low voltage ride-through, etc.) have not been addressed within this project.
Article
Installations of solar photovoltaic (PV) systems have been growing at a rapid pace in recent years. In 2009, approximately 7,500 megawatts (MW) of PV were installed globally, up from approximately 6,000 MW in 2008, consisting primarily of grid-connected applications. With 335 MW of grid-connected PV capacity added in 2009, the United States was the world's fourth largest PV market in 2009, behind Germany, Italy, and Japan. The market for PV in the United States is driven by national, state, and local government incentives, including up-front cash rebates, production-based incentives, requirements that electricity suppliers purchase a certain amount of solar energy, and federal and state tax benefits. These programs are, in part, motivated by the popular appeal of solar energy, and by the positive attributes of PV - modest environmental impacts, avoidance of fuel price risks, coincidence with peak electrical demand, and the possible deployment of PV at the point of use. Given the relatively high cost of PV, however, a key goal of these policies is to encourage cost reductions over time. Therefore, as policy incentives have become more significant and as PV deployment has accelerated, so too has the desire to track the installed cost of PV systems over time, by system characteristics, by system location, and by component. Despite the significant year-on-year growth, however, the share of global and U.S. electricity supply met with PV remains small, and annual PV additions are currently modest in the context of the overall electric system. To address this need, Lawrence Berkeley National Laboratory initiated a report series focused on describing trends in the installed cost of grid-connected PV systems in the United States. The present report, the third in the series, describes installed cost trends from 1998 through 2009, and provides preliminary cost data for systems installed in 2010. The analysis is based on project-level cost data from approximately 78,000 residential and non-residential PV systems in the U.S., all of which are installed at end-use customer facilities (herein referred to as 'customer-sited' systems). The combined capacity of systems in the data sample totals 874 MW, equal to 70% of all grid-connected PV capacity installed in the United States through 2009 and representing one of the most comprehensive sources of installed PV cost data for the U.S. The report also briefly compares recent PV installed costs in the United States to those in Germany and Japan. Finally, it should be noted that the analysis presented here focuses on descriptive trends in the underlying data, serving primarily to summarize the data in tabular and graphical form; later analysis may explore some of these trends with more-sophisticated statistical techniques. The report begins with a summary of the data collection methodology and resultant dataset (Section 2). The primary findings of the analysis are presented in Section 3, which describes trends in installed costs prior to receipt of any financial incentives: over time and by system size, component, state, system ownership type (customer-owned vs. third party-owned), host customer segment (residential vs. commercial vs. public-sector vs. non-profit), application (new construction vs. retrofit), and technology type (building-integrated vs. rack-mounted, crystalline silicon vs. thin-film, and tracking vs. fixed-axis). Section 4 presents additional findings related to trends in PV incentive levels over time and among states (focusing specifically on state and utility incentive programs as well as state and federal tax credits), and trends in the net installed cost paid by system owners after receipt of such incentives. Brief conclusions are offered in the final section, and several appendices provide additional details on the analysis methodology and additional tabular summaries of the data.
Article
Distributed generation (DG) can offer an alternative planning approach to utilities to satisfy demand growth and distribution network security, planning and management issues. However, an appropriate framework is required to foster the integration of DG within grid network planning, thus avoiding potential inefficiencies in electricity supply infrastructure. In this work, in order to capture the effects of network investment deferral on DG expansion, different regulations for distribution network operators (DNOs) ownership of DG and how they influence the optimal connection of new generation within existing networks are examined. Using a multiyear multiperiod optimal power flow, DNOs preference for the siting and sizing of DG installation are analyzed.
Article
In this report, we estimate the state-by-state per-capita “solar electric footprint” for the United States, defined as the land area required to supply all end-use electricity from solar photovoltaics (PV). We find that the overall average solar electric footprint is about 181 m2 per person in a base case scenario, with a state- and scenario-dependant range from about 50 to over 450 m2 per person. Two key factors that influence the magnitude of the state-level solar electric footprint include how industrial energy is allocated (based on location of use vs. where goods are consumed) and the assumed distribution of PV configurations (flat rooftop vs. fixed tilt vs. tracking). We also compare the solar electric footprint to a number of other land uses. For example, we find that the base case solar electric footprint is equal to less than 2% of the land dedicated to cropland and grazing in the United States, and less than the current amount of land used for corn ethanol production.
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An analysis of concentrating solar power with thermal energy storage in a California 33% renewable scenario; NREL/TP-6A20-58186
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Hummon, M.; Mehos, M. An analysis of concentrating solar power with thermal energy storage in a California 33% renewable scenario; NREL/TP-6A20-58186; National Renewable Energy Laboratory: Golden, CO, 2013. http://www.nrel.gov/docs/ fy13osti/58186.pdf (accessed July 23, 2013).
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) and weather data from the National Climatic Data Center (NCDC) (see Climate Forecast System Reanalysis (CSFR
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