Conference Paper

Synthetic Methanol and Dimethyl Ether Production based on Hybrid PV-Wind Power Plants

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Abstract

With growing concerns about climate change, this paper investigates the production cost of sustainable methanol (MeOH) and dimethyl ether (DME) from H2 and CO2 in a single-unit methanol or DME synthesis plant, powered by hybrid PV-Wind-Battery power plants. The CO2 is captured from the atmosphere and H2 is provided by water electrolysis. The overall efficiency of power-to-methanol (PtMeOH) and power-to-DME (PtDME) based on LHV would be 52.5% and 54.3%, respectively. The calculations are hourly resolved to find the least cost combination of technologies in a 0.45° × 0.45° spatial resolution, globally. The cost of hybrid PV-Wind electricity at best sites would be about 16-18 €/MWh. However, the electricity transmission for long distances (more than 1000 km) would increase the cost of delivered electricity to the PtX plants significantly. Results show that, for 7% WACC, RE-methanol and RE-DME can be produced in 2030 for a minimum cost of 400 €/tonne and 590 €/tonne, respectively. Considering access to oxygen sales and effective CO2 emissions costs, the production costs could effectively decrease to 290 €/tonneMeOH and 430 €/tonneDME. Thus, RE-methanol and RE-diesel could be produced to answer the fuel and chemical demand and remove environmental concerns at an affordable cost.

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... The processes and the cost of the fuels created from those processes were obtained from a model used by Fasihi et al. [34][35][36][37]. The model assumptions for hydrogen liquefaction were obtained from a 2011 study [38] conducted by the US Department of Energy which sought to significantly increase energy and cost savings in the liquefaction process. ...
... Fasihi et al.'s model [34][35][36][37] seeks to produce the lowest levelized cost of synfuel by optimizing a combination of PV, Wind, energy storage, transmission line and synthesis plant facilities. First, the landmass of Argentina was divided into 0.45°by 0.45°regions. ...
... The power production and consumption were calculated on an hourly basis and the power generated was always transmitted to the nearest coast where the PtX plants were located. With these restrictions and the design values used by Fasihi et al., the individual fuel prices were calculated [34][35][36][37][38]. ...
... Although the resource potential of ocean energy is high, its use is unfortunately not common. The support of ocean power technologies, especially by governments in Europe and North America, has strengthened electricity generation with ocean energy [21,22]. ...
... The largest regional market was Asia with 52%. Seven countries in Europe and two in Asia increased their capacity by 4.5 GW and global capacity by 24% to 23.1 GW [22]. ...
... Global energy-related carbon dioxide (CO 2 ) emissions increased by 1.7% in 2018 due to increased fossil fuel consumption. Fossil fuel use has increased by 11% since 2017 [22]. Fossil fuel companies continue to spend hundreds of millions of dollars on advertising to delay, control or thwart climate change policies and influence public opinion. ...
Article
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In the study, the current and future status of renewable energy resources were compiled in the light of large databases of national and international renewable energy institutions, and the latest situation in the world in the transition to 100% renewable energy was examined. The extent of the goal for the transition to 100% renewable energy has been determined, and predictions have been made based on all this information. In today's world where energy and environmental problems are on the agenda, countries' transition to renewable energy is the primary solution. This goal is called the transition to 100% renewable energy, which brings advantages such as providing needed energy and producing clean energy. Today, renewable energy sources account for more than one-third of the global energy capacity, and the world is rapidly moving towards 100% renewable energy. Compared with 2017, the total amount of renewable energy in 2018 increased by 181 GW, and the number of countries with an increase in the proportion of renewable energy increased. Taking into account the external dependence of the use of fossil fuels and environmental issues, this development is at a promising level in the future. In order to shift from highly polluting oil resources to natural gas and renewable resources, this article aims to investigate the current global energy transition trends, and then propose some important strategies to get closer to upstream goals and obligations in this way.
... However, Chile has utilised less than 1 % of the total techno-economic RE potential for electricity generation, which is naturally distributed across its continental territory. • Finally, Chile has been identified as one of the countries that has lowest costs for sustainable RE-based fuels and chemicals production [57][58][59]. ...
... The model has progressively been developed from the power sector [1,68] to the integration of power and heat [69], transport [70] and desalination [71] sectors, respectively. In the case of industrial fuels, the model has the capability to simulate the production of e-fuels (gaseous and liquid) [57,58] based on both green hydrogen [72] and CO 2 from direct air capture units [73], what is also known as power-to-X (PtX), but based on biomass as well. A detailed description of how the model works with all sectors integrated can be found in Bogdanov et al. [20,23]. ...
... In this sense, another opportunity for Chile to not only carry out a fully sustainable energy transition, but also contribute to the global energy transition, and utilise the full potential to produce sustainable RE-based fuels. The Atacama Desert and Patagonia have been identified as two of the best sites in the world for producing green hydrogen, synthetic gas and liquid fuels, and even chemicals [57][58][59]. It could even become a hot spot for CO 2 direct removal as part of a global net-negative post-2050 economy [119]. ...
Article
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The aim of this research is to analyse the impact of renewable energy (RE) technologies and sector coupling via analysing the transition pathways towards a sustainable energy system in Chile. Four energy transition scenarios for the power, heat, transport and desalination sectors were assessed using the LUT Energy System Transition model. The current policy scenario was modelled and compared with three best policy scenarios. The results showed that the transition to a 100 % renewable-based energy system by 2050 is technically feasible. Further, such an energy system would be more cost-efficient than the current policy scenario to reach carbon neutrality by 2050. The results also indicate that Chile could reach carbon neutrality by 2030 and become a negative greenhouse gas emitter country by 2035. In a 100 % renewable-based energy system, solar photovoltaics (PV) would contribute 86 % of electricity generation, which would represent 83 % of the total final energy demand for the year 2050. This would imply the use of about 10 % of the available techno-economic RE potential of the country. Three vital elements (high level of renewable electrification across all sectors, flexibility and RE-based fuel production) and three key enablers (solar PV, interconnection and full sectoral integration) were identified in order to transition to a fully sustainable energy system. Chile could contribute to the global sustainable energy transition and advance to the global post-fossil fuels economy through the clean extraction of key raw materials and RE-based fuels and chemicals production.
... Chile has been identified as one of the countries with the best sites (Atacama Desert and Patagonia) in the world for sustainable fuels and chemical products based on hybrid PV-wind power plants, such as liquids fuels (Fasihi et al., 2016), synthetic methanol and dimethyl ether (Fasihi & Breyer, 2017) and ammonia . According to (Fasihi et al., 2016), the RE-PtL value chain needs to be located at the best complementing solar and wind sites in the world combined with a de-risking strategy, and a special focus on mid to long-term electrolyser and H 2 tL efficiency improvements. ...
... In 2030, with a 7% WACC, the cheapest RE-methanol and RE-dimethyl ether can be produced in Atacama and Patagonia with a price in the range of 400-500 €/t and 590-750 €/t, respectively (Fasihi & Breyer, 2017). ...
Technical Report
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This document seeks to contribute to society and its decision-makers with the best available scientific evidence on Chile’s Renewable Energy (RE) Export Potential and the opportunities and challenges that such potential opens for Chile’s commitment to carbon neutrality. It also aims to provide a useful input for the dialogues that the country will hold in the framework of COP26. A collaborative and interdisciplinary process was developed for this goal, involving 71 researchers and specialists. The work includes 299 references of scientific literature that support the different dimensions involved in the challenge of exporting renewable energy from Chile. It is confirmed that Chile has a considerable renewable energy potential that can be the basis for various exports. The different energy export options identified are renewable electricity using electrical transmission grids; hydrogen and derivatives (synthetic fuels, fertilizers, other chemical products) through pipelines or maritime transport; local production or manufacturing of products and services fed with RE; and knowledge and R&D capabilities. We conclude that the whole process of renewable energy exports should be framed within the Chilean policy for climate change and the current local context. Moreover, such a process must be consistent with the social and environmental principles set out in Chile’s NDCs, in the future Framework Law for Climate Change, in its Long-Term Climate Strategy, and in the mitigation and adaptation plans of the energy sector. For this purpose, recommendations were developed in the following areas: Art. 6 of the Paris Agreement, climate observatory, legitimacy and social licence, just climate action principle, energy literacy, new challenges for science and technology, partnerships, and improvements of the current legislation.
... Currently, in literature there are two main synthesis routes for liquid energy carriers, namely methanol and Fischer-Tropsch synthesis [19]. Methanol synthesis uses CO 2 in combination with hydrogen as process inputs [20]. In the case of Fischer-Tropsch synthesis, CO is required. ...
... Even though the energy efficiency is significantly lower than in case of a direct use of electrical energy [20][21][22], the advantages are taken to be crucial for an ambitious decarbonisation scenario. ...
Chapter
As greenhouse gas (GHG) emissions need to be reduced in order to limit the effects of climate change, Life Cycle Assessment (LCA) provides an internationally recognized framework to evaluate the environmental impact of energy supply and application technologies. However, standard LCA approaches are unable to depict the high dynamics of the future energy system. High shares of renewable energies and more variable loads intensify these dynamics according to a wide range of energy system scenarios. Therefore, a dynamisation and modularisation of the classic LCA approach is proposed in order to easily integrate the simulated electricity generation from energy system models on an hourly basis as well as future energy technologies. A special focus is put on Power-to-X (PtX) technologies in the transport sector due to its potential in deep decarbonisation scenarios.
... 12,13 It is also increasingly better understood that the energy system in this century will be mainly based on electricity, finally due to high technical efficiency, comparable low cost, and the availability of respective power-to-X technologies. The power-to-X technologies include power-to-heat (electric heat pumps 14,15 ), power-to-water (reverse osmosis desalination 16 ), powerto-hydrocarbons (hydrogen, 17,18 methanation, [17][18][19][20] synthetic fuels, [20][21][22] and synthetic chemical feedstock [23][24][25][26], and a directly or indirectly electrified transport sector (battery electric vehicles, 27,28 marine, 29 and aviation 21 ). Decision makers increasingly require energy transition analyses with high spatial and temporal resolutions, so that the results can be discussed on a country or subcountry level in full hourly resolution and for demonstrating the feasibility of 100% RE systems. ...
Article
The power sector is faced with strict requirements in reducing harmful emissions and substantially increasing the level of sustainability. Renewable energy (RE) in general and solar photovoltaic (PV) in particular can offer societally beneficial solutions. The LUT energy system transition model is used to simulate a cost-optimised transition pathway towards 100% RE in the power sector by 2050. The model is based on hourly resolution for an entire year, the world structured in 145 regions, high spatial resolution of the input RE resource data, and transition steps of 5-year periods. The global average solar PV electricity generation contribution is found to be about 69% in 2050, the highest ever reported. Detailed energy transition results are presented for representative countries in the world, namely, Poland, Britain and Ireland, Turkey, Saudi Arabia, Brazil, Ethiopia, and Indonesia. The global average energy system levelised cost of electricity gradually declines from 70 €/MWh in 2015 to 52 €/MWh in 2050 throughout the transition period, while deep decarbonisation of more than 95% around 2040, referenced to 2015, would be possible. The targets of the Paris Agreement can be well achieved in the power sector, while increasing societal welfare, given strong policy leadership.
... "The Liquid Fuels Question" claims that "it is highly unlikely that synthetic liquid fuel substitutes for FFs [fossil fuels] can be produced sustainably in any more than small quantities for niche applications". Vast literature has been published in recent years on e-fuels and e-chemicals, such as green Hydrogen [85,86,163], e-Methane [164,165], Fischer-Tropsch fuels [166,167], e-Ammonia [168,169] and e-Methanol [170,171], all showing that electricity-based fuels are in reach. In a global energy system transition analysis reaching 100% RE in 2050 [46], with 90% electricity share in primary energy (mainly PV, wind and some hydropower) and strong growth in energy service demands, it has been shown that the total energy system cost can be kept at present levels, while the overall energy system efficiency can be increased by a factor of two [46], mainly due to the phase-out of combustion processes which can be substituted by direct electricity-based processes. ...
Article
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This paper exposes the many flaws in the article “Through the Eye of a Needle: An Ecoheterodox Perspective on the Renewable Energy Transition, authored by Siebert and Rees and recently published in Energies as a Review. Our intention in submitting this critique is to expose and rectify the original article’s non-scientific approach to the review process that includes selective (and hence biased) screening of the literature focusing on the challenges related to renewable energies, without discussing any of the well-documented solutions. In so doing, we also provide a rigorous refutation of several statements made by a Seibert–Rees paper, which often appear to be unsubstantiated personal opinions and not based on a balanced review of the available literature.
... For computational tractability, 4 h resolution is used instead, with 65,713 decision variables, solving in 8.5 min. The effects of aggregating time from one-hour to four-hour resolution are on the order of 1% of levelized fuel cost, discussed in the Supporting Information, Section S3. 10. ...
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Sectors such as aviation may require low-carbon liquid fuels to dramatically reduce emissions. This analysis characterizes the economic viability of electrofuels, synthesized from CO2 from direct air capture (DAC) and hydrogen from electrolysis of water, powered primarily by solar or wind electricity. This optimization-based techno-economic analysis suggests that using today’s technology, hydrocarbon electrofuels would cost upward of $4/liter of gasoline equivalent (lge), potentially falling to $1.7–1.8/lge in the next decade and <$1/lge by 2050. Only in the latter case are electrofuels potentially less costly than using petroleum fuels offset with DAC with sequestration. Achieving low-end electrofuel costs is contingent on substantial reductions in the capital cost of DAC, electrolyzers, and renewable electricity generation. However, the system also requires sufficient operational flexibility to efficiently power this capital-intensive equipment on variable electricity. Such forms of flexibility include various types of storage, supplementary natural gas and grid electricity interconnections (penalized with a steep carbon price), curtailment, and the ability to modestly adjust fuel synthesis and DAC operating levels over time scales of several hours to days.
... Supply-side technical production potential volumes and costs of RE-based chemicals (methanol, ammonia) are derived from modelling insights applied in the highly resolved modelling environment on 50-km and 1-h resolutions, as highlighted in Fasihi and Breyer 40,56 . ...
Technical Report
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Powerfuels – i. e. green hydrogen and derived gaseous and liquid energy carriers and feedstocks such as synthetic kerosene, methane or ammonia – will play an important role in a carbon-neutral energy system. They will be essential for defossilising sectors that are hard to electrify such as aviation, maritime transport, and specific industrial processes. In addition, they will play an important role in replacing fossil resources employed as process feedstocks. Furthermore, even in sectors with high electrification shares, there will be numerous applications relying on gaseous or liquid energy carriers. Here too, renewable liquid and gaseous energy carriers such as powerfuels will be essential for their defossilisation.
... The financial and technical assumptions can be found in Appendix A (Tables A1-A3). The assumptions for ammonia are taken from Fasihi et al. [94] and for methanol from Fasihi and Breyer [95]. The total chemicals demand is projected according to Fasihi et al. [50], thereof the ammonia demand projection is used from Fasihi et al. [94], and the naphtha by-product from FT synthesis is used first, while the remaining chemicals demand is supplied by methanol, as the fundamental chemical feedstock. ...
Article
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Transition towards long-term sustainable energy systems is one of the biggest challenges faced by the global society. By 2050, not only greenhouse gas emissions have to be eliminated in all energy sectors: power, heat, transport and industry but also these sectors should be closely coupled allowing maximum synergy effects and efficiency. A tool allowing modelling of complex energy system transition for power, heat, transport and industry sectors, responsible for over 75% of the CO2eq emissions, in full hourly resolution, is presented in this research and tested for the case of Kazakhstan. The results show that transition towards a 100% sustainable and renewable energy based system by 2050 is possible even for the case of severe climate conditions and an energy intensive industry, observed in Kazakhstan. The power sector becomes backbone of the entire energy system, due to more intense electrification induced sector coupling. The results show that electrification and integration of sectors enables additional flexibility, leading to more efficient systems and lower energy supply cost, even though integration effect varies from sector to sector. The levelised cost of electricity can be reduced from 62 €/MWh in 2015 to 46 €/MWh in 2050 in a fully integrated system, while the cost of heat stays on a comparable level within the range of 30–35 €/MWh, leading to an energy system cost on a level of 40–45 €/MWh. Transition towards 100% renewable energy supply shrinks CO2eq emissions from these sectors to zero in 2050 with 90% of the reduction achieved by 2040.
... Electrification is tearing down these sectoral barriers, mainly due to high technical efficiencies, comparably lower costs and the availability of prospective power-to-X technologies. These power-to-X technologies include power-to-heat (electric heat pumps 22,23 ), powerto-water (reverse osmosis desalination 24 ), power-to-hydrocarbons (hydrogen 25,26 , methanation 25,26,27,28 , synthetic fuels 28,29,30 , synthetic chemical feedstock 31,32,33,34 ), a directly or indirectly electrified transport sector 14 (battery electric vehicles 35,36 , marine 37,38 , aviation 29 ) and power-to-CO 2 for negative CO 2 emission technologies 39 , but also sustainable or non-avoidable carbon capture and utilisation (CCU) 40 . ...
Technical Report
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This is a first of its kind regional analysis of cost optimal energy transition pathway towards 100% renewables across the power, heat, transport and desalination sectors of North India. The study was undertaken before the pandemic but has become even more relevant considering the global call for green recovery. The study provides a long-term strategy for developing an economically viable integrated energy system enabling emissions reduction that will not only help with India’s climate commitments but also provide co-benefits of cleaner air and create millions of more jobs.
... The results of this study are in line with the findings of the research in this paper. Moreover, converting electricity to fuels or other chemical products powered by RE might be a viable alternative to fossil-based hydrocarbons in the mid-to long-term [114][115][116] and may be an excellent energy export opportunity for the MENA region in the decades to come. In addition, further business opportunities may arise for the MENA region for carbon direct removal, which is required to achieve the 1.5 � C target of the Paris Agreement, as addressed by Intergovernmental Panel on Climate Change [8]. ...
Article
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This research explores the feasibility of 100% renewable energy (RE) systems for the Middle East and North Africa (MENA) region for assumptions of the year 2030. The demand for three sectors are taken into account: power, non-energetic industrial gas and seawater desalination. Three strategical scenarios are discussed, namely Region, Area and Integrated, mainly differing in level of regional grid interconnection and sector coupling. Solar photovoltaics (PV) and wind energy are found to be the most cost-competitive RE sources with the highest potential in the region covering more than 90% of the generation capacity in all the considered scenarios. The variability of RE is solved via energy storage, surplus electricity generation and electricity grids. The estimated overall levelised cost of electricity (LCOE) lies between 40.3 and 52.8 €/MWh, depending on the scenarios. The total LCOE decreased by 17% as a result of sector coupling compared to the interconnected power sector alone. Power-to-gas technology not only functions as a seasonal storage by storing surplus electricity produced mainly from wind power and partially from solar PV, but provides also the required gas for the non-energetic industrial gas sector. Battery storage complements solar PV as a diurnal storage to meet the electricity demand during the evening and night time. Seawater reverse osmosis desalination powered by renewables could potentially be a proper solution to overcome the water challenges in the MENA region at affordable cost of 1.4 €/m³. A comparison with a BAU strategy shows that a 100% renewable energy-based power system is 55–69% cheaper than a BAU strategy without and with greenhouse gas emission costs.
... In the case of hydrogen production, the Atacama Desert represents the best place in the world [53]. At the same time, although there are no existing transmission lines that connect Patagonia with the rest of Chile to directly use the electricity generated from wind potential, this zone has the best combination between solar PV and wind to produce synthetic fuels [53,54]. Both the Atacama Desert solar potential and the Chilean Patagonia solar PV and wind potentials will play an important role in producing sustainable fuels in the energy transition for Chile. ...
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Renewable energies will play a significant role in transitioning towards sustainable energy system in order to match the goal under the Paris Agreement. However, to achieve this goal, it will be necessary to find the best country pathway, with global repercussions. This study reveals that an energy system based on 100% renewable resources in Chile would be technically feasible and even more cost-efficient than the current system. The Chilean energy system transition would imply a high level of direct and indirect electrification across all sectors. Simulation results using the LUT Energy System Transition model comprising 108 technology components show that the primary electricity demand would rise from 31 TWh to 231 TWh by 2050, which represents about 78% of the total primary energy demand. The remaining 22% would be composed of renewable heat and bioenergy fuels. Renewable electricity will mainly come from solar PV and wind energy technologies. Solar PV and wind energy installed capacities across all sectors would increase from 1.1 GW and 0.8 GW in 2015 to 43.6 GW and 24.8 GW by 2050, respectively. In consequence, the levelized cost of energy will reduce by about 25%. Moreover, the Chilean energy system in 2050 would emit zero greenhouse gases. Additionally, Chile would become a country free of energy imports.
Technical Report
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Did you know that European industry emissions are already larger than total coal power emissions in the EU? Did you also know that one in five jobs in Europe is in industry (50 million in total), which generates almost a quarter of Europe’s GDP? This means that 20% of Europe’s workforce and the basis of our welfare depend on a successful transition to a low-carbon economy. As other sectors modernise and decarbonise, industry will increasingly be exposed to demands for steep and rapid emission cuts. While there are many options that appear to address the issue of industrial emissions, only few have the potential to reduce emissions and even fewer can do so at scale. None are silver bullets. One certainty is that EU industry, unions and political leaders need to provide the basic climate infrastructure today that enables the low-carbon future and safeguards the jobs of tomorrow.
Technical Report
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Article
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The conventional configuration of a pulp mill, in which black liquor is concentrated and burnt, is compared with the upgrading gasification routes for methanol (MeOH) or dimethyl ether (DME) co-production. To this end, various exergy-based and environmental impact indicators are assessed in the light of different utility supply scenarios. The combined exergy and energy integration analysis is used to identify potential improvements related to the decarbonization and mitigation of the process irreversibility. As a result, the exergy efficiencies of the conventional scenario and the integrated plants average 40% and 45%, respectively, whereas the overall CO2 emission balances vary from 1.97 to-0.07 tCO2/tPulp, respectively. Additionally, an incremental economic analysis, that envisages future carbon taxation scenarios, suggests that only MeOH or DME co-production routes with partial electricity import may economically outperform the conventional kraft pulp mill for moderate carbon taxations. These results highlight the relevance of the electricity import from the Brazilian mix for pushing upwards the share of renewable energy resources in the production of traditionally fossil-based fuels and chemicals.
Chapter
Die zukünftigen Entwicklungen hinsichtlich des Verbrauchs und der Kosten von Fahrzeugen mit unterschiedlichen Antriebstechnologien werden an dieser Stelle untersucht. Zudem werden Preisprognosen für verschiedene Energieträger vorgestellt. Ein besonderer Fokus wird auf die zukünftigen Gasgestehungs- und Tankstellenkosten von Wasserstoff und synthetischem Methan wie auch auf die Stromkosten gelegt. Es wird gezeigt, dass sich vermutlich zukünftig die Herstellkosten von Fahrzeugen verschiedener Antriebstechnologien annähern. Dadurch steigt die Bedeutung der Energiekosten. Diesbezüglich wird eine deutliche Reduktion der Energiepreise für erneuerbare Energieträger sowie des Fahrzeugverbrauchs erwartet.
Article
The discussion about the benefits of a global energy interconnection is gaining momentum in recent years. The techno-economic benefits of this integration are broadly discussed for the major regions around the world. While there has not been substantial research on the techno-economic benefits, however, some initial results of the global energy interconnection are presented in this paper. Benefits achieved on the global scale are lower than the interconnections within the national and sub-national level. The world is divided into 9 major regions and the major regions comprise of 23 regions. When all the considered regions are interconnected globally, the overall estimated levelized cost of electricity is 52.5 €/MWh for year 2030 assumptions, which is 4% lower than an isolated global energy system. Further, the required installed capacities decrease by 4% for the fully interconnected system. Nevertheless, a more holistic view on the entire energy system will progress research on global energy interconnection as, synthetic power-to-X fuels and chemicals emerge as an important feature of the future sustainable global energy system with strong interactions of the power system not only to the supply, in energy fuel and chemicals trading globally, but also to the demand side. Global energy interconnection will be part of the solution to achieve the targets of the Paris Agreement and more research will help to better understand its impact and additional value.
Thesis
(In English Below) Obtener un sistema energético que contribuya a asegurar la estabilidad climática del planeta es uno de los desafíos más importantes de la primera mitad del siglo XXI. Con el propósito de contribuir en la búsqueda de vías que permitan superar la crisis climática global, pero desde acciones locales, y apelando a que la tecnología fotovoltaica (FV) cuenta con excelentes características para habilitar la transición energética que se necesita, esta tesis doctoral tiene como principal objetivo analizar, desde un enfoque global y local, el rol que la energía solar FV descentralizada podría jugar en la transición energética sostenible de un país y territorio específico. Para esto, se emplea como caso de estudio a Chile y particularmente, una de las regiones que lo conforma: la región de Aysén. Tanto Chile como la región de Aysén tienen aspectos que son un reflejo de la crisis global del Antropoceno, pero también cuentan con una gran oportunidad para implementar soluciones ejemplares basadas en sus enormes potenciales de energía renovable (ER). Para realizar dicho análisis se han considerado todos los sectores consumidores de energía y se utilizó una herramienta desarrollada por la Lappeenranta University of Technology (LUT), con la que se modelaron escenarios de transición energética hacia un sistema 100 % basado en ER para Chile, desde un enfoque global y local, donde, en el enfoque local se incluyó a la región de Aysén. Los resultados revelan que, tanto en Chile como en la región de Aysén, lograr un sistema energético 100% renovable para el año 2050 es técnicamente factible y económicamente viable. En ese año, dependiendo del enfoque y escala territorial, la contribución a la generación eléctrica por parte de la tecnología FV en su conjunto varía entre 39–86 % y, la contribución de la FV descentralizada varía entre 9–12 %; no obstante, la FV descentralizada aporta entre un 27–52 % de la electricidad final que es mayormente consumida en las ciudades por los sectores eléctrico, térmico y transporte. A su vez, la energía solar FV descentralizada crearía en Chile entre el 9–15 % de los empleos anuales directos durante el periodo de transición. Es decir, entre los años 2020 y 2050, el sector de la FV descentralizada crearía 174.274 empleos directos. Además, los resultados también revelan que Chile puede alcanzar la neutralidad en emisiones de carbono en el año 2030 y, se puede convertir en un país emisor negativo de gases de efecto invernadero a partir del año 2035. Todo esto sería posible utilizando menos del 10 % del potencial tecno-económico de ER disponible en este país. Tras los resultados del trabajo de investigación realizado en esta tesis doctoral, se concluye que la energía solar FV es un elemento vital en la transición energética sostenible, así como también, alcanzar un sistema energético totalmente desfosilizado es más importante que lograr la neutralidad en las emisiones de carbono. Esto último se debe a que una transición a nivel país hacia un sistema energético 100 % renovable implicaría beneficios socio-ambientales y socioeconómicos locales, con impactos globales positivos que se necesitan con urgencia. Si Chile implementara una vía de transición hacia un sistema energético 100 % renovable, no solo podría convertirse en un caso ejemplar en el avance hacia una economía post-combustibles fósiles, si no que también podría contribuir a la transición energética global: a través de la extracción limpia de materias primas clave (como lo son el cobre y el litio), y a través de la producción de combustibles y químicos basados en ER. En resumen, la tecnología FV puede contribuir en la mitigación del cambio climático y la reducción de los niveles de contaminación del aire en las ciudades, al tiempo que impulsa el crecimiento económico local; todo esto, de una manera más descentralizada y participativa. ///////////////////////////////////////// Obtaining an energy system that will help to ensure the climactic stability of the planet is one of the most important challenges of the first half of the 21st century. In order to contribute to the search for ways to overcome the global climate crisis, from local activities, and appealing to the fact that photovoltaic (PV) technology has excellent characteristics which could enable the energy transition that is needed, this doctoral thesis has as its main objective the analysis, from a global and local approach, the role that decentralized solar PV could play in the sustainable energy transition of a specific country and territory. For this purpose, Chile and one of its regions (the Aysén region) are used as a case study. Both Chile and the Aysén region have aspects that reflect the global crisis of the Anthropocene, but they also present a great opportunity to implement exemplary solutions, based on their enormous renewable energy (RE) potentials. To carry out this analysis, all energy-consuming sectors were considered. A tool developed by the Lappeenranta University of Technology (LUT) was used, with which energy transition scenarios were modelled towards a 100% RE-based system for Chile, from a global and local approach. The Aysén region was included in the local approach. The results reveal that, both in Chile and in the Aysén region, achieving a 100% RE system by 2050 is technically feasible and economically viable. In that year, depending on the approach and territorial scale, the contribution to electricity generation by PV technology as a whole would vary between 39–86%. The contribution of decentralized PV would be between 9–12%. However, decentralized PV would contribute 27–52% of the final electricity that is mostly consumed in cities by the power, heat and transport sectors. In turn, decentralized solar PV would create between 9–15% of annual direct jobs in Chile during the transition period. In other words, between 2020 and 2050, the decentralized PV sector would create 174,274 direct jobs. In addition, the results also reveal that Chile could achieve carbon neutrality in 2030 and could become a negative greenhouse gas emitter by 2035. All of this would be possible by using less than 10% of the techno-economic potential of RE available in this country. From the results of the research work carried out in this doctoral thesis, it is concluded that solar PV is a vital element in the sustainable energy transition. We also find that achieving a fully defossilized energy system is more important than achieving carbon neutrality. The latter is due to the fact that a transition at the country level towards a 100% RE system would imply local socio-environmental and socio-economic benefits, with positive urgently needed global impacts. If Chile implements a transition path towards a 100% RE system, it could not only become an exemplary case in moving towards a post-fossil fuel economy, but could also contribute to the global energy transition through the clean extraction of key raw materials (such as copper and lithium), and through the production of RE-based fuels and chemicals. In summary, PV technology can contribute to mitigating climate change and reducing air pollution levels in cities, while boosting local economic growth, doing all of this in a more decentralized and participatory way.
Chapter
In diesem Kapitel werden Potenziale hinsichtlich des Verbrauchs und der Kosten von Fahrzeugtechnologien dargelegt. Zudem werden mögliche Preisentwicklungen für verschiedene Energieträger vorgestellt. Ein besonderer Fokus wird auf die zukünftigen Gasgestehungs- und Tankstellenkosten von Wasserstoff und synthetischem Methan wie auch auf die Stromkosten gelegt. Es wird gezeigt, dass sich vermutlich zukünftig die Herstellkosten von Fahrzeugtechnologien annähern. Dadurch steigt die Bedeutung der Energiekosten. Es ist eine deutliche Reduktion der Energiepreise für erneuerbare Energieträger sowie des Fahrzeugverbrauchs erwartbar.
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Photovoltaic installations are usually guaranteed to operate for 25 to 30 years, with a warranty of 80% of initial performance remaining after this time. However, in order to determine the profitability of a project, it is important to estimate the performance of the photovoltaic modules over their lifetime, depending on their environment. In this study, a first version of an ageing model for photovoltaic systems is considered, taking into account the influence of the environmental stress factors, which are the temperature, the relative humidity, and the exposure to UV radiation. Another stress factor also needs to be taken into account: the module's voltage potential versus ground (Potential Induced Degradation). The impact of cell cracks on the modules is also included in the model, their impact over the years depending on the temperature, but mainly to thermal cycles, due to the differences in temperature between day and night (thermal dilatation). Accelerated Damp Heat tests, thermal cycling tests, PID tests and UV tests are interpreted and used for calibrating the model, in addition to other degradation studies taken from relevant literature. A simple model is first built for the corrosion, with the temperature and humidity as stress factors, considering only the maximum power degradation. A more advanced model is then built, considering the degradation of the two-diode model parameters. A model has been built for each degradation, that is to say corrosion (temperature and humidity), AR coating and EVA discoloration (UV exposure), PID causes (temperature, humidity and voltage), and cell cracks (Thermal cycling). First simulations have been done, with weather data from the south of France (Mediterranean climate), Miami (hot and humid), and Dubai (hot and dry) showing that the power output after 30 years is still above the warranty limit of 80%.
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This paper assesses two different carbon capture and utilization (CCU) routes as disposal options for captured CO2 emissions. The adopted methodology is presented and applied to the study of urea synthesis and methanol production. Process flow modelling is used to analyze their technological performances. The adopted conceptual design strategy allows for the contextualization of the modelled technologies and their comparison in terms of selected scales and process configurations. The results highlight the potential benefit of CO2 utilization, by avoiding CO2 emissions. The proposed approach is amenable for the screening of other prospective technologies: polymer synthesis, CO2 mineralization and formic acid production, which will be addressed by the Joint Research Centre (JRC) in a follow-up study of CCU.
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Conference Paper
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PV and wind power are the major renewable power technologies in most regions on earth. Depending on the interaction of solar and wind resources, PV and wind power industry will become competitors or allies. Time resolved geospatial data of global horizontal irradiation and wind speeds are used to simulate the power feed-in of PV and wind power plants assumed to be installed on an equally rated power basis in every region of a 1°x1° mesh of latitude and longitude between 65°N and 65°S. An overlap of PV and wind power full load hours is defined as measure for the complementarity of both technologies and identified as ranging between 5% and 25% of total PV and wind power feed-in. Critical overlap full load hours are introduced as a measure for energy losses that would appear if the grid was dimensioned only for one power plant of PV or wind. In result, they do not exceed 9% of total feed-in but are mainly around 3% - 4%. Thus the two major renewable power technologies must be characterized by complementing each other.
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This manual is a guide for analyzing the economics of energy efficiency and renewable energy (EE) technologies and projects. It is intended: (1) to help analysts determine the appropriate approach or type of analysis and the appropriate level of detail, and (2) to assist EE analysts in completing consistent analyses using standard assumptions and bases, when appropriate. Included are analytical techniques that are commonly required for the economic analysis of EE technologies and projects. The manual consists of six sections: Introduction, Fundamentals, Selection Criteria Guide, Economic Measures, Special Considerations for Conservation and Renewable Energy Systems, and References. A glossary and eight appendices are also included. Each section has a brief introductory statement, a presentation of necessary formulae, a discussion, and when appropriate, examples and descriptions of data and data availability. The objective of an economic analysis is to provide the information needed to make a judgment or a decision. The most complete analysis of an investment in a technology or a project requires the analysis of each year of the life of the investment, taking into account relevant direct costs, indirect and overhead costs, taxes, and returns on investment, plus any externalities, such as environmental impacts, that are relevant to the decision to be made. However, it is important to consider the purpose and scope of a particular analysis at the outset because this will prescribe the course to follow. The perspective of the analysis is important, often dictating the approach to be used. Also, the ultimate use of the results of an analysis will influence the level of detail undertaken. The decision-making criteria of the potential investor must also be considered.
Thesis
As electricity generation based on volatile renewable resources is subject to fluctuations, data with high temporal and spatial resolution on their availability is indispensable for integrating large shares of renewable capacities into energy infrastructures. The scope of the present doctoral thesis is to enhance the existing energy modelling environment REMix in terms of (i.) extending the geographic coverage of the potential assessment tool REMix-EnDaT from a European to a global scale, (ii.) adding a new plant siting optimization module REMix-PlaSMo, capable of assessing siting effects of renewable power plants on the portfolio output and (iii.) adding a new alternating current power transmission model between 30 European countries and CSP electricity imports from power plants located in North Africa and the Middle East via high voltage direct current links into the module REMix-OptiMo. With respect to the global potential assessment tool, a thorough investigation is carried out creating an hourly global inventory of the theoretical potentials of the major renewable resources solar irradiance, wind speed and river discharge at a spatial resolution of 0.45°x0.45°. A detailed global land use analysis determines eligible sites for the installation of renewable power plants. Detailed power plant models for PV, CSP, wind and hydro power allow for the assessment of power output, cost per kWh and respective full load hours taking into account the theoretical potentials, technological as well as economic data. The so-obtined tool REMix-EnDaT can be used as follows: First, as an assessment tool for arbitrary geographic locations, countries or world regions, deriving either site-specific or aggregated installable capacities, cost as well as full load hour potentials. Second, as a tool providing input data such as installable capacities and hourly renewable electricity generation for further assessments using the modules REMix-PlasMo and OptiMo. The plant siting tool REMix-PlaSMo yields results as to where the volatile power technologies photovoltaics and wind are to be located within a country in order to gain distinct effects on their aggregated power output. Three different modes are implemented: (a.) Optimized plant siting in order to obtain the cheapest generation cost, (b.) a minimization of the photovoltaic and wind portfolio output variance and (c.) a minimization of the residual load variance. The third fundamental addition to the REMix model is the amendment of the module REMix-OptiMo with a new power transmission model based on the DC load flow approximation. Moreover, electricity imports originating from concentrating solar power plants located in North Africa and the Middle East are now feasible. 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The scope of this study is the techno-economic evaluation of the Power to Methanol (PtM) concept, valorising CO2 that comes from high CO2 emitting lignite-fired power plants, in order to investigate the prospect of PtM in a future energy market of high RES penetration and advanced lignite-fired power plants. The concept was examined for the case of Greece. Two distinct case studies were selected, regarding the entity that makes the investment in PtM: a) the power plant owner case and b) the private investor case. The study focused on the estimation of the MeOH cost for a marginally feasible investment by fulfilling techno-economic criteria. In the case of the power plant owner the MeOH cost was estimated at 421€/tn MeOH and was about 40% lower than the cost calculated for the private investor case (580€/tn MeOH), due to the higher operating capacity of the H2 and MeOH plants and the lower electricity cost in the first case. The MeOH cost was further decreased in both cases by considering: a) large plant scales, b) low electricity cost, c) high operating time for the H2 and MeOH plants, d) low CO2 costs and/or e) low discount rates. Following the results for Greece, the power plant owner case was also examined for Germany and proved to be even more sustainable, due to the lower electricity cost in Germany.
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The direct hydrogenation of CO2 into dimethyl ether (DME) has been studied in a fixed bed reactor (TR: 220–260 °C; PR: 5.0 MPa; GHSV: 8800 NL/Kgcat/h), in presence of CuZnZr-ferrierite hybrids combining in a single pellet the metal-oxide sites responsible for CO2 activation/hydrogenation and the acidic sites for MeOH dehydration to DME. Two different preparation methods (i.e., impregnation and gel-oxalate coprecipitation) have been adopted to evaluate how the metal loading and element interdispersion over the bidimensional lamellar structure of the ferrierite affect the nature and morphology of the active sites. A CuZnZr:FER weight ratio greater than 1 allowed to obtain the best activity-selectivity pattern on the co-precipitated samples, attaining a CO2 conversion of 23.6% at 260 °C and a cumulative MeOH/DME yield of ca. 15%. The effects of experimental conditions on the activity-selectivity pattern were also investigated, to disclose the preferential reaction pathways leading to higher DME selectivity.
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This study demonstrates how seawater reverse osmosis (SWRO) plants, necessary to meet increasing future global water demand, can be powered solely through renewable energy. Hybrid PV–wind–battery and power-to-gas (PtG) power plants allow for optimal utilisation of the installed desalination capacity, resulting in water production costs competitive with that of existing fossil fuel powered SWRO plants. In this paper, we provide a global estimate of the water production cost for the 2030 desalination demand with renewable electricity generation costs for 2030 for an optimised local system configuration based on an hourly temporal and 0.45° × 0.45° spatial resolution. The SWRO desalination capacity required to meet the 2030 global water demand is estimated to about 2374 million m3/day. The levelised cost of water (LCOW), which includes water production, electricity, water transportation and water storage costs, for regions of desalination demand in 2030, is found to lie between 0.59 €/m3–2.81 €/m3, depending on renewable resource availability and cost of water transport to demand sites. The global system required to meet the 2030 global water demand is estimated to cost 9790 billion € of initial investments. It is possible to overcome the water supply limitations in a sustainable and financially competitive way.
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In order to define a cost optimal 100% renewable energy system, an hourly resolved model has been created based on linear optimization of energy system parameters under given constrains. The model is comprised of five scenarios for 100% renewable energy power systems in North-East Asia with different high voltage direct current transmission grid development levels, including industrial gas demand and additional energy security. Renewables can supply enough energy to cover the estimated electricity and gas demands of the area in the year 2030 and deliver more than 2000 TW hth of heat on a cost competitive level of 84 €/MW hel for electricity. Further, this can be accomplished for a synthetic natural gas price at the 2013 Japanese liquefied natural gas import price level and at no additional generation costs for the available heat. The total area system cost could reach 69.4 €/MW hel, if only the electricity sector is taken into account. In this system about 20% of the energy is exchanged between the 13 regions, reflecting a rather decentralized character which is supplied 27% by stored energy. The major storage technologies are batteries for daily storage and power-to-gas for seasonal storage. Prosumers are likely to play a significant role due to favourable economics. A highly resilient energy system with very high energy security standards would increase the electricity cost by 23% to 85.6 €/MW hel. The results clearly show that a 100% renewable energy based system is feasible and lower in cost than nuclear energy and fossil carbon capture and storage alternatives.
Article
This study investigates various design and operating aspects for the valorization of industrially captured CO2 towards methanol production and the circumstances under of which this concept can be economically viable. Cost breakdown in various Power-to-Fuel concepts confirm that hydrogen cost is the most crucial factor. Several power delivery options for hydrogen production through electrolysis are compared for their economics. The use of cheap electricity in conjunction with adequate time coverage throughout the annum is of high importance for lowering the overall H2 production costs. Also, a Power-to-Fuel system integrated with a coal fired power plant can be an interesting option for excess power transformation when the electricity sell is not profitable. The economic analysis on the H2 production scheme revealed that each of the three main parameters for the determination of the H2 cost (electrolyzer capital cost, electricity cost and storage cost) can play the key role in the feasibility of the plant depending on the concept each time. A considerable effort is needed in order the CO2 derived fuels to reach a competitive level in the global market.
Article
Power-to-gas (PtG) technology has received considerable attention in recent years. However, it has been rather difficult to find profitable business models and niche markets so far. PtG systems can be applied in a broad variety of input and output conditions, mainly determined by prices for electricity, hydrogen, oxygen, heat, natural gas, bio-methane, fossil CO2 emissions, bio-CO2 and grid services, but also full load hours and industrial scaling. Optimized business models are based on an integrated value chain approach for a most beneficial combination of input and output parameters. The financial success is evaluated by a standard annualized profit and loss calculation and a subsequent return on equity consideration. Two cases of PtG integration into an existing pulp mill as well as a nearby bio-diesel plant are taken into account. Commercially available PtG technology is found to be profitable in case of a flexible operation mode offering electricity grid services. Next generation technology, available at the end of the 2010s, in combination with renewables certificates for the transportation sector could generate a return on equity of up to 100% for optimized conditions in an integrated value chain approach. This outstanding high profitability clearly indicates the potential for major PtG markets to be developed rather in the transportation sector and chemical industry than in the electricity sector as seasonal storage option as often proposed.
Article
The production of hydrogen from renewable sources by water electrolysis can be coupled to a downstream chemical synthesis. This enables the production of liquid fuels or chemical raw materials that can be used in today's infrastructure. However, it is not clear which synthesis technology fits best to the novel boundary conditions for chemical plants (e.g. small scale, flexible operation). In order to identify the most promising syntheses, different one-stage synthesis systems are evaluated in terms of technology, economics and acceptance. The analysis gives in all cases production costs that are significantly above today's market prices. Fischer-Tropsch (FT) synthesis routes are expected to have a higher public acceptance compared to the other technologies due to the high product similarity to conventional energy carriers (diesel, crude oil). The economic feasibility of synthetic natural gas (SNG) production suffers from the low product price of natural gas as a benchmark, but its technical score is high. Methanol production is identified as the synthesis technology that achieves the highest overall score. The analysis shows that not only techno-economic parameters, but also parameters representing the public acceptance like the fit to the existing infrastructure, have to be considered to identify appropriate technologies that may play a role in future energy systems.
Conference Paper
Mehrere fundamentale Faktoren beschränken die Stabilität der weltweiten Elektrizitätsversorgung. Diese sind insbesondere die stetig zunehmende Nachfrage, sich erschöpfende fossile und nukleare Energieressourcen, Emissionen von sehr schädlichen Treibhausgasen, erhebliche Energieungerechtigkeit und ein global unausgeglichener ökologischer Fußabdruck. Photovoltaik (PV) Systeme werden hinsichtlich mehrerer Aspekte - speziell wirtschaftliche und technische - auf ihren ergänzenden und ersetzenden Energiebeitrag zum limitierten konventionellen Energiesystem untersucht. Um den optimalen Systemansatz für PV Kraftwerke abzuleiten werden mehrere solare Ressourcen, die an die jeweiligen PV Systeme angepasst sind, verglichen. Infolge der ökonomischen Bewertung der solaren Ressourcen werden zwei besonders wettbewerbsfähige PV Systeme identifiziert. Das Konzept der Erfahrungskurven wird als wesentliche Methode für wirtschaftliche Projektionen in den 2010er Jahren genutzt. Die Haupttreiber für Kostensenkungen bei PV Systemen sind die Lernrate der Technologie und die Wachstumsrate der Produktion. Für diese werden die relevanten Aspekte diskutiert: Investitionen in Forschung und Entwicklung, technisches PV Marktpotenzial, zahlreiche PV Technologien und die energetische Nachhaltigkeit der PV. Die drei wesentlichen Marktsegmente der PV sind PV Lösungen für netzferne Gebiete, dezentralisierte kleinere netzgekoppelte PV Systeme (einige kWp) und große PV Kraftwerke (Vielfaches von 10 MWp). Das weltweite ökonomische Marktpotenzial für alle wesentlichen PV Marktsegmente wird hauptsächlich durch die Anwendung der ‘grid-parity‘ und ‘fuel-parity‘ Konzepte abgeleitet. Das Hybridisierungspotenzial von PV Kraftwerken in Bezug auf alle relevanten Kraftwerksarten wird auf seine technische, wirtschaftliche und geografische Machbarkeit hin untersucht. Die wesentlichen Erfolgsfaktoren für hybride PV Kraftwerke werden diskutiert und umfassend für Öl, Gas und Kohle gefeuerte Kraftwerke, Windkraft, solarthermische Kraftwerke (STEG) und Wasserkraftwerke analysiert. Für die 2010er Jahre werden detaillierte weltweite Nachfragekurven für hybride PV-Fossile Kraftwerke unter Einbezug aller fossilen Kraftwerke, Länderdaten und Brennstoffarten ermittelt. Die fundamentalen technischen und ökonomischen Potenziale von hybriden PV-STEG, hybriden PV-Wind und hybriden PV-Wasserkraftwerken werden betrachtet. Die weltweite Ressourcenverfügbarkeit für PV und Windkraft ist exzellent, weswegen es von größter Bedeutung ist, ob sich PV und Windkraft durch eine kompetitive oder komplementäre Beziehung zueinander auszeichnen. Die Komplementarität von hybriden PV-Windkraftwerken wird bestätigt. Es ergibt sich daher keine Reduktion des globalen ökonomischen PV Marktpotenzials und Systeme auf der Basis von hybriden PV-Windkraftwerken sind sehr wahrscheinlich. Das zentrale Ziel lautet erneuerbare Kraftwerkstechnologien in das globale Elektrizitätssystem zu integrieren und dabei eine Durchdringung von 100% zu erreichen. Neben Ausgleichskapazitäten werden hierfür Speicher benötigt, insbesondere für die saisonale Elektrizitätsspeicherung. Erneuerbares Methan (RPM) bietet sich hierfür an. Eine umfassende weltweite Analyse untersucht Elektrizitätssysteme auf der Basis von hybriden PV-Wind-RPM-Gaskraftwerken. Ein solches Elektrizitätssystem könnte unter Einbezug des Wärme- und Transportsektors und sogar der Chemieindustrie wettbewerbsfähig sein und nahezu alle heutigen Beschränkungen überwinden. Hybride PV Kraftwerke stellen eine äußerst attraktive Option zur Elektrizitätsversorgung dar. Die Photovoltaik wird gemeinsam mit der Windkraft die Solar- und Windenergie als hauptsächliche und finale Energiequellen für die Menschheit etablieren.
Article
This study demonstrates – based on a dynamical simulation of a global, decentralized 100% renewable electricity supply scenario – that a global climate-neutral electricity supply based on the volatile energy sources photovoltaics (PV), wind energy (onshore) and concentrated solar power (CSP) is feasible at decent cost. A central ingredient of this study is a sophisticated model for the hourly electric load demand in >160 countries. To guarantee matching of load demand in each hour, the volatile primary energy sources are complemented by three electricity storage options: batteries, high-temperature thermal energy storage coupled with steam turbine, and renewable power methane (generated via the Power to Gas process) which is reconverted to electricity in gas turbines. The study determines – on a global grid with 1°x1° resolution – the required power plant and storage capacities as well as the hourly dispatch for a 100% renewable electricity supply under the constraint of minimized total system cost (LCOE). Aggregating the results on a national level results in an levelized cost of electricity (LCOE) range of 80-200 EUR/MWh (on a projected cost basis for the year 2020) in this very decentralized approach. As a global average, 142 EUR/MWh are found. Due to the restricted number of technologies considered here, this represents an upper limit for the electricity cost in a fully renewable electricity supply.
Article
The activity and durability of two hybrid bifunctional dimethyl ether (DME) synthesis catalysts: 6CuO–3ZnO–Al2O3/γ-Al2O3 and 6CuO–3ZnO–1Al2O3/HZSM-5, have been evaluated for the conversion of CO2/H2 to DME at 260 °C, 5 MPa, and gas per hourly space velocity (GHSV) of 3000 mL gcat−1 h−1 in fixed-bed and slurry reactors. The catalyst 6CuO–3ZnO–Al2O3/γ-Al2O3 mostly promoted reverse-water-gas-shift (RWGS) reaction with very low selectivity to DME, and a low conversion of CO2. The other catalyst, 6CuO–3ZnO–1Al2O3/HZSM-5, showed much higher conversion of CO2 with higher selectivity to DME in both, fixed-bed and slurry reactors.
Article
We present a geographical assessment of the performance of crystalline silicon photovoltaic (PV) modules over Europe. We have developed a method that is based on a material specific analytical expression of the PV conversion efficiency, relative to nominal efficiency, as a function of module temperature and irradiance. This method is combined with a climate database that includes average daytime temperature and irradiance profiles. It is found that the geographical variation in ambient temperature and yearly irradiation causes a decrease in overall yearly PV performance from 3 to 13% relative to the performance under Standard Test Conditions, with the highest decrease found in the Mediterranean region. Based on the above results we developed a simplified linear expression of the relative PV module efficiency that is a simple function of yearly total irradiation and yearly average daytime temperature. The coefficients to the linear expression are found by fitting to the map resulting from the above-mentioned analytical approach. The prediction of total yearly PV output from this linear fit deviates less than 0·5% from the more detailed calculation, thus providing a faster and more simplified alternative to the yield estimate, in the case when only limited climate data are available. Copyright © 2008 John Wiley & Sons, Ltd.
Chapter
The world is currently consuming about 85 million barrels of oil a day, and about two-thirds as much natural gas equivalent, both derived from non-renewable natural sources. In the foreseeable future, our energy needs will come from any available alternate source. Methanol is one such viable alternative, and also offers a convenient solution for efficient energy storage on a large scale. In this updated and enlarged edition, renowned chemists discuss in a clear and readily accessible manner the pros and cons of humankind's current main energy sources, while providing new ways to overcome obstacles. Following an introduction, the authors look at the interrelationship of fuels and energy, and at the extent of our non-renewable fossil fuels. They also discuss the hydrogen economy and its significant shortcomings. The main focus is on the conversion of CO2 from industrial as well as natural sources into liquid methanol and related DME, a diesel fuel substitute that can replace LNG and LPG. The book is rounded off with an optimistic look at future possibilities. A forward-looking and inspiring work that vividly illustrates potential solutions to our energy and environmental problems.
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Carbon Asset Risk: From Rhetoric to Action
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Surface meteorology and Solar Energy (SSE) release 6.0 Methodology
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Assessment of Mid-Term Growth Assumptions and Learning Rates for Comparative Studies of CSP and Hybrid PV-Battery Power Plants
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Comprehensive technoeconomic assessment of dimethyl ether (DME) synthesis and Fischer-Tropsch synthesis as alternative process steps within biomass-to-liquid production
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