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Abstract

Wind energy has developed rapidly over the last two decades to become one of the most promising and economically viable sources of renewable energy. Although wind energy is claimed to provide clean renewable energy without any emissions during operation, but it is only one side of the coin. The blades, one of the most important components in the wind turbines, made with composite, are currently regarded as unrecyclable. With the first wave of early commercial wind turbine installations now approaching their end of life, the problem of blade disposal is just beginning to emerge as a significant factor for the future. This paper is aimed at discovering the magnitude of the wind turbine blade waste problem, looking not only at disposal but at all stages of a blade’s lifecycle. The first stage of the research, the subject of this paper, is to accurately estimate present and future wind turbine blade waste inventory using the most recent and most accurate data available. The result will provide a solid reference point to help the industry and policy makers to understand the size of potential environmental problem and to help to manage it better. This study starts by estimating the annual blade material usage with wind energy installed capacity and average blade weight. The effect of other waste contributing factors in the full lifecycle of wind turbine blades is then included, using industrial data from the manufacturing, testing and in-service stages. The research indicates that there will be 43 million tonnes of blade waste worldwide by 2050 with China possessing 40% of the waste, Europe 25%, the United States 16% and the rest of the world 19%.

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... They offer no viable workarounds for the ecological damage and deplorable working conditions, often in the Global South, involved in metal ore extraction [6,7]. The waste streams generated by so-called renewables at the end of their short working lives are either ignored or assumed away, to be dealt with eventually by yet non-existent recycling processes [8][9][10]". ...
... Sovacool [6,7] reports alarming cases of forced labor in Africa and mafia-like operations in Latin America, but concludes that "ample opportunities exist to make low-carbon world more pluralistic, demographic and just". The S-R's statement that the "end of their short working lives are either ignored or assumed away, to be dealt with yet non-existent recycling technologies" is even more elusive as their own references [8][9][10] do not support this argument. Chowdhary et al. [8] reviews several PV recycling technologies and highlights the need for recycling to become obligatory worldwide (it is already obligatory in the EU and solar modules are about to be included in a revision of the European Union's Eco-design Directive (Directive 2009/125/EC)). ...
... Xu et al. [9] provide a quantitative basis to support the recycling of PV panels. Liu and Barlow [10] admit that the recycling of the blades of wind turbines is still in development and estimate what the demand for recycling will be in the future, more or less the opposite of "ignored" or "assumed away." ...
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.
... A wind turbine has a design life of approximately 20 years and therefore many of the initial installations from the first commercial wind farms are fast approaching their decommissioning stage (Beauson and Brøndsted, 2016;Liu and Barlow, 2017). In addition, wind farm repowering is leading to wind turbines being taken down prior to their 20 year design life. ...
... This is creating a rising environmental concern due to the potentially large volumes of waste from the composite blades, which will need to be managed (Liu and Barlow, 2016). Liu and Barlow (2017) estimate that by 2050 there will be a cumulative total of around 43 million tonnes of blade waste globally and there will be around 2 million tonnes per year by 2050. This cumulative estimate agrees with Bank et al. (2018a) which was obtained using the future "moderate scenario growth" wind power estimates from the Global Wind Energy Council (GWEC, 2016). ...
... There is risk of a rapid accumulation of EOL blades, which will prove difficult to address, without advanced planning and preparation (Andersen et al., 2016). Liu and Barlow (2017) recognise the need to accurately predict waste quantities to help policy makers, governments and the manufacturing industry to prioritise waste reduction and minimise environmental impacts. A limited number of studies has attempted to conduct such research. ...
Article
The End-of-Life (EOL) stage of the first commercial wind farms is fast approaching and uncertainty remains in how to deal with their non-biodegradable Fibre Reinforced Polymer (FRP) composite wind turbine blades. Repurposing options could potentially delay large volumes of material entering unsustainable waste streams such as landfill or incineration and contribute to the circular economy. To plan waste management methods as well as inform the collective team of policy makers, decision makers and local governments, it is essential to understand and assess the geographical variability in the quantity of potential FRP composite blade waste material. Decisions regarding EOL blades are complex due to the varying numbers of blades and diversity in models, therefore it is essential that decommissioning plans are tailored for each location. This research introduces an innovative spatiotemporal approach to investigate the magnitude of the problem and quantify blade waste material associated with the EOL stage of wind turbine blades using the island of Ireland case study. The technical and spatiotemporal variability is assessed through an integrated Geographical Information Science (GIS) framework and online dashboard for decision-making. The findings indicate that for the island of Ireland approximately 53,000 tonnes of composite material will reach the EOL stage by 2040 with highest material densities located in the west and southwest of the island. The integrated GIS approach provides important information on blade type and model to assist decision-making on the design of repurposing strategies for FRP composite blades and provides an exemplar for other countries.
... Currently, they are not considered re-cyclable due to their complex multi-material structure [3]. Neutralization and collection of fiber-reinforced polymer composites currently takes place through mechanical processes such as: processing the material into fillers, reinforcements, thermal processes-energy recovery or thermo-chemical processes [4][5][6]. ...
... According to research conducted in this field, by 2050, there will be 43 million tons of wind turbine waste in the world, of which individual regions of the world will have: 40 % China, 25 % Europe, 16 % USA, 19 % the rest of the world [4], Figure 1. Annual production of shovel waste in Europe will be 325 000 tons while wind power will reach 450 GW [11]. ...
... Projected wind turbine waste in 2050[4]. ...
Article
Circular waste management is the answer to the daily waste of all types. Wind power plants installed in the 1990s are ending their service life of turbine blades, hence the need to properly manage this waste. The aim of the article is to investigate the mechanical properties of mining and industrial waste The article presents the results of research on geopolymers based on coal shale of the Staszic mine and waste from wind turbine blades in three types of compositions: 50/50, 72/25, 25/75. The results of the research show that these materials can be used as fillers for products that do not require high strength values. Die Kreislaufwirtschaft ist die Antwort auf den täglichen Abfall aller Art. Windkraftanlagen, die in den 1990er Jahren installiert wurden, beenden ihre Lebensdauer der Rotorblätter, daher muss dieser Abfall ordnungsgemäß entsorgt werden. Ziel des Artikels ist es, die mechanischen Eigenschaften von Bergbau‐ und Industrieabfällen und Abfall von Rotorblättern in den Zusammensetzungen 50/50, 72/25, 25/75 zu untersuchen. Die Forschungsergebnisse zeigen, dass diese Materialien als Füllstoffe für Produkte verwendet werden können, die keine hohen Festigkeitswerte erfordern. The aim of research is to show the possibilities of using waste materials from the mining industry as well as the energy industry for production of geopolymer materials. The results of research show that these materials can be used as fillers for products that not require high strength values. Use of such fillers for geopolymer matrix would potentially allow a significant use and reduce waste.
... Increasingly, several recent studies have specifically focused on addressing the concern related to the blade waste generation from the wind power sector in future decades. Liu and Barlow (2017) conducted a study to estimate the wind turbine blade waste until 2050, mainly for China, the United States, and Europe. The waste was carefully estimated throughout all the life cycle stages, from the manufacturing process to the EoL. ...
... The turbine blade mass data is not available for most wind turbine models installed in Canada to date; data from the above manufacturers are assumed to be representative of all producers. We estimate blade mass based on turbine blade diameter (Liu and Barlow, 2017), and calculate the weighted average blade weight per unit power based on current wind turbines installed in Canada. The weighted average for the modelled blade mass per unit rated power is estimated to be 12.35 tonnes/MW by considering 47 different turbine models (see Fig. S2 in SI). ...
... Wind turbine blade waste is estimated by considering waste generation at manufacturing, operational & maintenance (O&M), and EoL stages ( Fig. 1). Manufacturing and O&M wastes are estimated following a similar approach by (Liu and Barlow, 2017), and waste generation rates are shown in Table 1. Manufacturing waste arises due to in-process wastes, blade testing process, and defective blades. ...
Article
Electricity production by wind turbines is considered a clean energy technology, but the life cycle of wind turbines could introduce environmental risks due to waste generation, especially at the decommissioning process. This study predicts the future wind turbine blade waste arising in Canada, throughout all life cycle stages, from manufacturing until end of life, based on the installed capacities of existing Canadian wind farms and projected future installations. Five alternative strategies for managing this waste stream are assessed in terms of life cycle greenhouse gas emissions and primary energy demand, including landfilling, incineration, and mechanical recycling. For the base case scenario, it is observed that the total cumulative waste until 2050 is 275,299 tonnes, with on-site waste accounting for around 75% of this total. Waste generation is concentrated in provinces with greater wind power deployment: Ontario and Quebec alone account for 70% of total blade waste. Life cycle environmental impacts of waste management strategies are dependent on background energy systems, with incineration a significant source of greenhouse gas emissions, particularly when displacing low-carbon grid mixes. Cement kiln coprocessing achieves net zero emission by converting waste into energy and raw materials for the cement. Mechanical recycling can achieve substantial reductions in primary energy demand and greenhouse gas emissions but achieving financial viability would likely require substantial regulatory support.
... Many countries worldwide install wind turbines to increase the renewable energy share. However, as early commercial wind turbine installations now approach their end of life (EOL), the problem of rotor blade material recycling/recovery is emerging (Liu and Barlow 2017;Ortegon et al., 2013). Until today, recycling of rotor blades is not possible (Liu and Barlow 2017) or difficult. ...
... However, as early commercial wind turbine installations now approach their end of life (EOL), the problem of rotor blade material recycling/recovery is emerging (Liu and Barlow 2017;Ortegon et al., 2013). Until today, recycling of rotor blades is not possible (Liu and Barlow 2017) or difficult. Amongst other reasons, this is based on uncertainties regarding the materials used in rotor blades, so that many studies describe potential rotor blade material compositions (Andersen et al., 2016;Zimmermann and Gößling-Reisemann 2012;Garret et al. 2011Garret et al. , 2013aEymann et al., 2015;Geuder 2004;Vestas 2006;D'Souza et al., 2011;Martinez et al., 2009;Ghenai 2012;Razdan and Garrett 2017). ...
... Literature quantifies expected rotor blade waste on national level (Ortegon et al., 2013 (US); Andersen et al., 2016 (SE); Arias 2016 (US); Pehlken et al., 2017 (GER); Sultan et al., 2018 (UK); Zotz et al., 2019 2 (GER, onshore only); Tota-Maharaj and McMahon 2020 (UK)), in Europe (Sommer et al., 2020;Lichtenegger et al., 2020) and worldwide (Lefeuvre et al., 2019;Liu and Barlow 2017;Larsen 2009). Various models estimate the rotor blades' masses depending on their properties. ...
Article
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Worldwide, wind turbine stocks are ageing and questions of reuse and recycling particularly of rotor blades become urgent. Especially, rising rotor blade wastes face lacking good recycling options and exact quantification is difficult due to information gaps on the rotor blade size, mass and exact material composition. In a combined approach, the expected rotor blade waste is quantified and localized on a national level for Germany until 2040. Fibre-reinforced plastics (FRP) from rotor blades are in focus and differentiated into two material classes: glass-fibre reinforced plastics (GFRP) and glass- and carbon-fibre reinforced plastics (GFRP/CFRP). The quantification approach is based on a national power plant stock database (Marktstammdatenregister) and regression models, combined with a power class-based estimation for missing datasets. As a result, between 325,726 and 429,525 t of waste from the GFRP material class and between 76,927 t and 211,721 t of waste from the GFRP/CFRP material class arise from obsolete rotor blades in Germany until 2040. This corresponds to a share of between 11% and 32% of wind turbines with GFRP/CFRP rotor blade material in Germany. For GFRP, waste peaks in 2021, 2035 and 2037 are expected with around 40,000 t of waste per year. For GFRP/CFRP, waste peaks in 2036 and 2037 will induce more than 20,000 t/a. Mostly affected federal states are Lower Saxony, Brandenburg, North Rhine-Westphalia and Schleswig-Holstein. The methods are applicable and transferable to other countries, particularly with ageing wind turbines fleets.
... This research therefore investigates the problem of handling end-of-life (EoL) blades and mainly looks at the problem of the composite parts, due to the fact that a standard wind turbine blade consists of 90 wt% composite material and the rest of the content is a mixture of PVC, balsa wood, metal, paint and sealing. According to various studies [13][14][15] the general composition of a blade is: composite material ~93% PVC ~2% balsa wood ~2% metal, paint and putty ~3% Some of the first wind turbine blades were designed from the National Advisory Committee for Aeronautics (NACA) profiles, which, over time, have been optimized, and there are now many different profile types used by individual manufacturers [16]. Although many different manufacturers exist, most WTBs are constructed more or less alike A typical structure is seen in Figure 1, in which the blades consist of three main parts: two aerodynamic shells (on the compression side and the tension side), which are joined together and stiffened by either one or several integral (shear) webs or by a box beam [14,17] Figure 1. ...
... By determining the amount of waste in wt% (percentage by total mass) from the individual categories, it is possible to estimate a total future annual amount of waste from wind turbine blades. Based on a study prepared by [13], a median for the At present, most of the blades consist of polymer composite reinforced with glass fibers (GF); some are reinforced with carbon fibers (CF), and more and more hybrid combinations of glass fibers and carbon fibers are being introduced. The resin is most often high-grade epoxy or polyester. ...
... By determining the amount of waste in wt% (percentage by total mass) from the individual categories, it is possible to estimate a total future annual amount of waste from wind turbine blades. Based on a study prepared by [13], a median for the amount of composite material used per MV installed wind turbine was determined. The study was based on 14 different wind turbine manufacturers and their [13,15,22]. ...
Article
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Wind energy has seen an increase of almost 500 GW of installed wind power over the past decade. Renewable energy technologies have, over the years, been striving to develop in relation to capacity and size and, simultaneously, though with less focus on, the consequences and challenges that arise when the products achieve end-of-life (EoL). The lack of knowledge and possibilities for the recycling of fiber composites and, thus, the handling of EoL wind turbine blades (WTBs) has created great environmental frustrations. At present, the frustrations surrounding the handling are based on the fact that the most commonly used disposal method is via landfills. No recycling or energy/material recovery is achieved here, making it the least advantageous solution seen from the European Waste Commission’s perspective. The purpose of this research was thus to investigate the current recycling methods and to categorize them based on the waste materials. The opportunities were compared based on processing capacity, price, environment and technology readiness level (TRL), which concluded that recycling through co-processing in the cement industry is the only economical option at present that, at the same time, has the capabilities to handle large amounts of waste materials.
... Some EU nations have prohibited the disposal of composite blades in landfills for environmental [4], necessitating the development of novel EOL solutions for composites in this industry. The used scrap blade materials are anticipated to double in the next decade, from 1,000,000 t in 2020 to 2,000,000 t in 2030 [22]. An estimated 25% of all EOL trash will be generated in the EU, according to estimates [12]. ...
... wt% GF. Owing to the existence of hazardous metals and organic substances, as well as GFs, the recovery of WPCBs to retrieve GFs is a difficult procedure [7,22]. ...
Article
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The rising usage of carbon and glass fibers has raised awareness of scrap management options. Every year, tons of composite scrap containing precious carbon and glass fibers accumulate from numerous sectors. It is necessary to recycle them efficiently, without harming the environment. Pyrolysis seems to be a realistic and promising approach, not only for efficient recovery, but also for high-quality fiber production. In this paper, the essential characteristics of the pyrolysis process, their influence on fiber characteristics, and the use of recovered fibers in the creation of a new composite are highlighted. Pyrolysis, like any other recycling process, has several drawbacks, the most problematic of which is the probability of char development on the resultant fiber surface. Due to the char, the mechanical characteristics of the recovered fibers may decrease substantially. Chemically treating and post-heating the fibers both help to reduce char formation, but only to a limited degree. Thus, it was important to identify the material cost reductions that may be achieved using recovered carbon fibers as structural reinforcement, as well as the manufacture of high-value products using recycled carbon fibers on a large scale. Recycled fibers are cheaper than virgin fibers, but they inherently vary from them as well. This has hampered the entry of recycled fiber into the virgin fiber industry. Based on cost and performance, the task of the current study was to modify the material in such a way that virgin fiber was replaced with recycled fiber. In order to successfully modify the recycling process, a regulated optimum temperature and residence duration in post-pyrolysis were advantageous.
... It is estimated that composite materials from blades worldwide will amount to 330,000 tonnes of waste per year by 2028, and 418,000 tonnes per year by 2040 (Ramirez-Tejeda et al., 2017). By 2050, other loses in manufacture, transport, and operation, such as severe weather damage, has been estimated to total 0.8Mt each year (Liu & Barlow, 2017). ...
... Composite blades are, by their very nature, a combination of different materials, which represent a further challenge in terms of separation and varying chemistry. At the global scale, the cumulative total blade waste is expected to reach 2.9 Mt per year by 2050 (Liu & Barlow, 2017) and turbine blades are increasing in size as development continues. ...
Article
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This article reviews the environmental, ecological, and social impacts of current renewable energy technologies. Problems of these technologies are highlighted in terms of manufacturing, installation, lifetime, and end-of-life. What emerges are concerning issues that need to be urgently addressed as they potentially threaten the recovery of the Earth system and therefore also impact society. It is suggested that many of these issues have been overlooked because of our focus on carbon reduction, which, while important, may lead to a failure to deal with other equally concerning threats, and even exacerbate them. These threats are highlighted and then urgent priorities, in terms of policy, regulation, and research, are identified, paving the way to an energy future that does not threaten the functionality of the Earth system. Finally, key underlying themes are identified that may inform our decision-making as we move forward. If we are to aim for a truly sustainable future, in terms of economics, ecology, and society, this article argues that we must seek to aim higher than current practice and plan for a future that not only arrests anthropogenic climate destabilization and its threat to many species, including our own, but that builds the foundations for ecological recovery. Better-than-before is not good enough. We need energy technologies that minimize our impact on our planet.
... Among all OWT components, blade waste recycling and reuse are the most important topics [227][228][229]. The blades are made from composite materials, which are energy-intensive to manufacture and environmentally problematic. ...
... Therefore, the disposal and recycling of broken blades represent valuable research topics. Blade waste is predicted to significantly increase in upcoming decades; there is a clear linear trend between blade mass and power rating [227]. ...
Article
Operations and maintenance of offshore wind turbines (OWTs) play an important role in the development of offshore wind farms. Compared with operations, maintenance is a critical element in the levelized cost of energy, given the practical constraints imposed by offshore operations and the relatively high costs. The effects of maintenance on the life cycle of an offshore wind farm are highly complex and uncertain. The selection of maintenance strategies influences the overall efficiency, profit margin, safety, and sustainability of offshore wind farms. For an offshore wind project, after a maintenance strategy is selected, schedule planning will be considered, which is an optimization problem. Onsite maintenance will involve complex marine operations whose efficiency and safety depend on practical factors. Moreover, negative environmental impacts due to offshore maintenance deserve attention. To address these issues, this paper reviews the state-of-the-art research on OWT maintenance, covering strategy selection, schedule optimization, onsite operations, repair, assessment criteria, recycling, and environmental concerns. Many methods are summarized and compared. Limitations in the research and shortcomings in industrial development of OWT operations and maintenance are described. Finally, promising areas are identified with regard to future studies of maintenance strategies.
... Generally, blades and nacelle are likely to be decommissioned after 20-25 years (Nijssen and Brøndsted, 2013). These reinforced polymers are inert in nature and provide the required stability and strength to the structure, but since these materials are made from the crossed linked thermoset polymers, they cannot be easily degraded in landfills (Liu and Barlow, 2017). Even incinerating these materials may result in toxic emissions e.g. ...
... For determining the blade material, the blades are categorized into four categories: 1 MW, 1-1.5 MW, 1.5-2 MW, 2-5MW and larger than 5 MW. B a s e d o n e x p e r i m e n t s performed in other studies, the corresponding material may be assumed as the following: 8.43 tonnes/MW for less than 1 MW; 12.37 tonnes/MW for 1-1.5 MW; 13.41 tonnes/MW for 1.5-2 MW; 12.58 tonnes/MW for more than 5 MW (Liu and Barlow, 2017). The manufacturing waste is assumed to be generated in first year of installation and taken as 17.2% of the material installed. ...
Chapter
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The understanding of the harmful effects of fossil fuels and its impact on global warming have led to the growth of renewable sources of energy in India and the world as a whole. This study presents an overview of wind energy in India and across the globe. The study assesses the quantum of waste generated from the adoption of wind energy system in India and reviews various end-of-life options for wind blades from the literature reviews/ studies.
... Green New Dealers advance no viable solutions (technical or financial) for electrifying the many high-heat-intensive manufacturing processes involved in constructing high-tech wind turbines and solar panels (not to mention all other products in modern society) [22][23][24][25]. The waste streams generated by so-called renewables at the end of their short working lives are either ignored or assumed away, to be dealt with eventually by yet non-existent recycling processes [26][27][28]. Proposals for electrifying the 80% of nonelectrical energy demand overlook crucial facts, namely that the national-scale transmission systems and grids required for electrified land transportation do not even exist today, nor is the needed build-out likely given material, energy, and financial constraints [29]. ...
... A 3.1 MW wind turbine creates anywhere from 772 to 1807 tons of landfill waste, 40 to 85 tons of waste sent for incineration, and about 7.3 tons of e-waste [20]. Wind turbine blades, made of composite materials, are completely unrecyclable at present [28]. ...
Article
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We add to the emerging body of literature highlighting cracks in the foundation of the mainstream energy transition narrative. We offer a tripartite analysis that re-characterizes the climate crisis within its broader context of ecological overshoot, highlights numerous collectively fatal problems with so-called renewable energy technologies, and suggests alternative solutions that entail a contraction of the human enterprise. This analysis makes clear that the pat notion of “affordable clean energy” views the world through a narrow keyhole that is blind to innumerable economic, ecological, and social costs. These undesirable “externalities” can no longer be ignored. To achieve sustainability and salvage civilization, society must embark on a planned, cooperative descent from an extreme state of overshoot in just a decade or two. While it might be easier for the proverbial camel to pass through the eye of a needle than for global society to succeed in this endeavor, history is replete with stellar achievements that have arisen only from a dogged pursuit of the seemingly impossible.
... Composite materials are desirable for design engineers in the construction sector to build elaborate and irregular envelopes and facades [9]. In the wind energy sector, as turbine blades become longer than 50 m, the use of polymer matrix composites is the most sought-after solution [10]. The automotive industry also uses composite materials to produce sheet molding compound (SMC) and dough molding compound (DMC), as well as boat hulls [1,11]. ...
... Projections made by EuCia indicate that around 66,000 tons of thermoset composite will originate from wind turbine blades in 2025, representing only 10% of the total estimated thermoset composite waste for the same year [24]. Looking forward to the future, there are a massive 43 million tons of blades expected to be recycled in 2050, as a consequence of the intensive installation of wind towers to fulfil green energy source targets [10,18]. Consequently, wind energy as a green source should be reconsidered. ...
Article
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In this paper, a review of the current status and future perspectives for reinforced glass fiber waste is undertaken, as well as an evaluation of the management hierarchy for these end-of-life materials. Waste levels are expected to increase in the coming years, but an improvement of collection routes is still necessary. The recycling processes for these materials are presented. The associated advantages and disadvantages, as well as the corresponding mechanical characteristics, are described. Although mechanical shredding is currently the most used process, there is a potential for thermal processes to be more competitive than others due to the fiber quality after the recycling process. However, the energy requirements of each of the processes are not yet well explained, which compromises the determination of the economic value of the recycled fibers when included in other products, as well as the process feasibility. Nevertheless, the work of some authors that successfully integrated recycled glass fibers into other elements with increased mechanical properties is evaluated. Future recommendations for the recycling of glass fiber and its commercialization are made.
... As an example of the potential end-of-engineered-life challenge of offshore wind turbine blades, a typical 6 MW wind turbine has a blade length of 75 m (approximately the same length as an A380 aeroplane wingspan) and mass per unit rated power of 12.58 tonnes/MW [21], i.e. 75.5 tonnes per blade and 3 blades per turbine. With 16,435 wind turbines forecast to have been installed in our oceans by 2040 (Fig. 3), this sets up a significant volume of composite to manage at the end-of-engineered-life. ...
Article
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Thousands of structures are currently installed in our oceans to help meet our global energy needs. This number is set to increase with the transition to renewable energy, due to lower energy yield per structure, growing energy demand and greater and more diverse use of ocean space (e.g. for food, industrial or scientific activity). A clear and comprehensive picture of the spatial and temporal distribution of ocean energy assets is crucial to inform marine spatial planning, sustainable design of ocean infrastructure and end-of-engineered-life management, to prevent an exponentially increasing asset base becoming an economic and environmental burden. Here we define the spatial and temporal dimensions of the challenge that lies before us through creation of a comprehensive global dataset of past, current and forecast ocean energy infrastructure and offshore energy resources, both hydrocarbon and wind, for the period 1960–2040. The data is collected together for the first time and made available in the public domain through an interactive online map. The resulting oceanscape provides insight into the type, quantity, density and geographic centres of the accumulating asset base, which in turn enables informed consideration of how marine space alongside design and end-of-engineered-life of ocean infrastructure can be managed responsibly and sustainably.
... The problem with closing the cycle of products made of composites, however, is a multisector problem. The construction sector, the electric and electronic industry, transport and the maritime sector also have a problem with post-consumer polymer waste management [8][9][10][11][12]. ...
Article
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Wind power plants during generation of electricity emit almost no detrimental substances into the milieu. Nonetheless, the procedure of extraction of raw materials, production of elements and post-use management carry many negative environmental consequences. Wind power plant blades are mainly made of polymer materials, which cause a number of problems during post-use management. Controlling the system and the environment means such a transformation of their inputs in time that will ensure the achievement of the goal of this system or the state of the environment. Transformations of control of system and environment inputs, for example, blades production, are describing various models which in the research methodology, like LCA (Life Cycle Assessment), LCM (Life Cycle Management), LCI (Life Cycle Inventory), etc. require meticulous grouping and weighing of life cycle variables of polymer materials. The research hypothesis was assuming, in this paper, that the individual post-production waste of wind power plant blades is characterized by a different potential impact on the environment. For this reason, the aim of this publication is to conduct an ecological and energy life cycle analysis, evaluation, steering towards minimization and development (positive progress) of selected polymer waste produced during the manufacture of wind power plant blades. The analyzes were based on the LCA method. The subject of the research was eight types of waste (fiberglass mat, roving fabric, resin discs, distribution hoses, spiral hoses with resin, vacuum bag film, infusion materials residues and surplus mater), which are most often produced during the production of blades. Eco-indicator 99 and CED (Cumulative Energy Demand) were used as the computation procedures. The influence of the analyzed objects on human health, ecosystem quality and resources was appraised. Amidst the considered wastes, the highest level of depreciating impact on the milieu was found in the life cycle of resin discs (made of epoxy resin). The application of recycling processes would decrease the depreciating environmental influence in the context of the total life cycle of all analyzed waste. Based on the outcome of the analyzes, recommendations were proposed for the environmentally friendly post-use management of wind power plant blades, that can be used to develop new blade manufacturing techniques that better fit in with sustainable development and the closed-cycle economy.
... The wind turbine industry is expected to stockpile millions of tons of composite wind blades in the coming years [1]. These structures are mainly manufactured from E-Glass fiber (with some use of Carbon fiber) embedded in epoxy, polyester, or vinyl ester resins [2]. ...
Article
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This paper demonstrates the concept of adaptive repurposing of a portion of a decommissioned Clipper C96 wind turbine blade as a pole in a power transmission line application. The current research program is aimed at creating a path towards sustainable repurposing of wind turbine blades after they are removed from service. The present work includes modelling and analysis of expected load cases as prescribed in ASCE 74 and NESC using simplified boundary conditions for tangent pole applications. Load cases involving extreme wind, concurrent ice and wind, extreme ice, differential ice, broken conductor, and broken shield have been analyzed and governing load cases for bending, shear, and torsion have been examined. Relative stiffnesses of different parts forming the wind blade’s cross section (i.e., shell, web, and spar cap) are determined. The corresponding stresses associated with each part under the governing loads are compared to allowable strength values which are determined from composite laminate theory and modelling of the known laminate structure of the E-Glass FRP material. Stresses and deflections obtained are compared with governing reliability-based design criteria and code requirements. The results of the structural analysis indicate that the wind blade can resist the expected loads with reasonable safety factors and that the expected deflections are within permissible limits. Recommendations are provided for detailing and modification of the wind blade for a power pole application in which crossarm and davit connections are highlighted, and foundation details are emphasized.
... The increasing number of wind turbine installations and their expected growth in size and number in the next few years gives rise to an imminent challenge of disposal of end-of-life blades (8). By 2051, an estimated 43 million tons of blades will be retired globally (16% in the United States) (9). The major component of most blades is GFRP, and only a small fraction is structural foam and metals. ...
Article
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Millions of tons of glass fiber reinforced polymer (GFRP) waste have been steadily generated from end-of-life wind turbine blades and many other GFRP composites prevalent in everyday life, with limited reuse options. Recycled GFRP (rGFRP) by mechanical processing could be used in mortar and concrete as fibers or fillers. Maintaining the composite nature of rGFRP with a high fiber content is paramount to increased mechanical properties for concrete. In this study, high-modulus rGFRP particles were produced in three small, medium, and large relative sizes by hammer milling and screening. Small and medium rGFRPs were used in 1, 2, 3%, and large rGFRP in 1, 2, 3, 5, and 7% volume replacing sand in mortar. Almost all rGFRP-mortars showed significant improvement in flexural strength with their high modulus. All size groups of rGFRP progressively showed higher fracture toughness at higher amounts. Within the large group, 5 and 7%Vol had flexural toughness of about 2.00J compared with 0.75J of 3%Vol. Large rGFRP at 5 and 7%Vol offered nearly 60% and 70% 28 day equivalent flexural ratio. Micrographs of rGFRP–matrix interfaces from fracture faces showed rGFRP was well embedded within the matrix, provided bridging and deflecting of microcracks, and failed in pullout or rupture modes. Fly ash and silica fume had a positive synergy with 3%Vol large rGFRP and improved its flexural toughness from 0.75J to 1.12 and 1.00J, respectively. The investigated recycling process and sizes of rGFRP shreds showed great promise in this exploratory study and are recommended for further evaluation for highway and bridge concrete.
... The European Composites Industry Associaton (EuCIA) has estimated that the mass of composite materials used to manufacture wind turbines is already 2.5 million tonnes. In 2050, the mass of these materials is expected to reach 43 million tonnes, where 25% will be in Europe, 40% in China, 16% in the United States and 19% in the rest of the world [2]. ...
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This paper concerns the recycling of waste material from wind turbine blades. The aim of the research was to determine the possibility of using ground waste material derived from the exploited structures of wind turbines as a filler in geopolymer composites. In order to determine the potential of such a solution, tests were carried out on three different fractions originating from the ground blades of wind turbines, including an analysis of the morphology and chemical composition of particles using SEM and an EDS detector, the analysis of organic and inorganic matter content and tests for multivariate geopolymer composites with the addition of waste material. The compression and flexural strength, density, and absorbability tests, among others, were carried out. The composite material made of the geopolymer matrix contained the filler at the level of 5%, 15%, and 30% of dry mass. The addition of the filler showed a tendency to decrease the properties of the obtained geopolymer composite. However, it was possible to obtain materials that did not significantly differ in properties from the re-reference sample for the filler content of 5% and 15% of dry mass. As a result of the research, it was found that waste materials from the utilization of used wind power plants can become fillers in geopolymer composites. It was also found that it is possible to increase the strength of the obtained material by lowering the porosity.
... Nevertheless, mechanical recycling is considered to be the only mature and environmentally friendly process found in the current market. [16] 1.1.2 | Thermal recycling Thermal recycling methods are mainly used to recover pure solid residues that are the reinforcing fibers. ...
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Waste from hundreds of thousands of tons of non‐recyclable end‐of‐life wind turbine blades will be generated within the next decades. This work studies the effect of recycled fiber categories on the tensile properties of reinforced polylactic acid (PLA) specimens made by fused filament fabrication 3D printing. Three different fiber categories, that is, virgin, ground, and pyrolyzed, are examined and compared experimentally and analytically using micromechanical models. Tensile tests are performed on different PLA specimens prepared with the three fiber categories and two fiber contents of 5% and 10% per ASTM D638. Compared to virgin fibers, both recycled fibers, that is, ground and pyrolyzed fibers, exhibit higher strength and stiffness values. Ground recycled fibers showed higher ultimate tensile strength compared to the pyrolyzed ones, while higher stiffness values were obtained for pyrolyzed fibers. Single fiber tensile tests, pull‐out interfacial strength tests, thermal analysis, and microscopic imaging are performed to evaluate parameters used in the micromechanical models. The Halpin‐Tsai and Cox models showed good agreement with the experimental modulus results with errors less than 5% for pyrolyzed fibers, while the minimum prediction error was 24.1% for strength results.
... This expansive growth on energy generation is reflected to technological development, as well as in the development of increasingly tall and slender wind turbines, and as a consequence, these turbines can suffer severe dynamic excitations, thus reaching the service limit state for excessive vibrations [2,3]. ...
... A blade's mass follows an approximately third-degree exponential increase as a function of blade length (Brøndsted et al. 2005). Given the number of wind turbines in operation and nearing their end-of-service life, it is anticipated that millions of tons of blade waste will need to be disposed of in the next 20 years (Liu and Barlow 2017). ...
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This paper focuses on the conceptual use of a fiber-reinforced polymer (FRP) wind turbine blade that is repurposed for a second life as an electrical transmission pole. Thousands of tons of fiber-reinforced polymer composite wind turbine blades are currently coming out of service globally and are being landfilled or incinerated. These are not environmentally preferable disposal methods. This paper presents a detailed structural analysis of a Clipper C96, 46.7-m-long turbine blade used as an electrical pole. The analytical procedure needed to characterize the wind turbine blade for repurposing includes determining the external and internal geometry of the blade, identifying the types of materials and laminates used throughout the blade, and calculating effective moduli and section properties for structural analysis. Code-specified load combinations are then used to analyze the transmission line BladePole to determine internal forces and deformations and stresses. Maximum stresses were compared to those obtained from theoretical models. The results indicate that wind turbine blades can safely be used as electrical transmission poles.
... According to some estimates, the demand for polymer composite materials will reach 150 thousand tons by 2020, which is 52% more than in 2014 [1,2]. Considering the life cycle of products, the volume of to-be-disposed reinforced composite materials could reach 1-3% of their annual production [3][4][5][6]. ...
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The technical feasibility of the recycling of specific polymeric composite materials was evaluated. Two types of carbon composites, both with phenol-formaldehyde resin but with different reinforcement, were studied. It was discovered that the solvolysis with the oxidizing agents used in an acidic environment allowed for the achievement of a high-efficiency fiber extraction. The extracted secondary carbon fibers had a high degree of purity (95–99.5% of resin was removed). Fiber thickness slightly decreased during the process (on average, by 20%). The use of chopped secondary fibers (3–9 mm fiber length) for concrete reinforcement produced a positive effect. Hence, the compressive and bending strength of the concrete blocks were accordingly 1.5% and 16% higher in comparison with the control sample. The use of secondary carbon fabric for the production of composite materials a good result: the effective tensile strength of CFRP samples reinforced with recovered fabric is only lower by 4.5% in comparison with virgin fabric.
... In addition, due to the applications of more advanced technologies, the costs for wind farm will be slashed by about 40% in 2050 (Wiser et al., 2021), making the utilization of wind power more promising. However, by 2050, China will cumulatively produce nearly 17.2 million tons wind turbine blade wastes (Liu and Barlow, 2017). Recycling and reuse of the blade wastes are costly, energy consuming and may release toxic gases (Rani et al., 2021). ...
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As apanoramic overview of the multipronged national-scale regulations of China to synchronously decelerate climate change and improve air quality, this study pores through a constellation of China's strategies aimed to obtain coinstantaneous reductions in the emissions of atmospheric pollution and greenhouse gases (GHGs). These strategies, inclusive of afforestation and silviculture, ultra-low industrial emissions, energy structure reform, renewable energy development, household emission reductions, transportation emission control, and shutdown of cryptocurrency mining, have vouchsafed China new pragmatic dimensions in pursuit of its climate goals and have established a roadmap to bide time for the future. Here we show blow-by-blow the pros and cons of these pathways to illustrate the reasons why they best serve China's long-term targets and dovetail with China's geopolitical realities. Because of the interactions between air pollutants and GHGs, cooperatively reducing the emissions of both air pollutants and climate change gases have mutual benefits and are efficacious for the enhancement of air quality and mitigation of global warming.
... Due to the ever rising growth of wind power, the end-of-life (EOL) wastes from the WT blades is one of the major environmental problems [22][23][24][25]. FRPCs such as glass FRPCs (GFRPCs) and carbon FRPCs (CFRPCs) are commonly used in WT blades to give improved strength and stiffness to weight ratios, ease of producing needed forms, and inexpensive manufacturing and material costs (GF composites). ...
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Large number of wind turbines which have been installed by the wind energy industry in the last three decades will become scrap in near future. Wind turbine blades are the most sophisticated and at the same time, one of the largest part of the wind energy systems. During the breakdown or at the end of life period of a blade, the disposal of the blade material is a serious concern. Hence, the study of recycling and reusing the wind turbine blade is essential. The present work is a review on recycling and reuse of wind turbine blades that includes techniques of recycling, diverse materials used for blade manufacturing, wastage of materials during the different stages of its lifecycle and the energy consumption of particular recycling processes along with the energy content of the blade materials. The commonly used materials for wind turbine blades are polymers (Polyester (PE) resin, Epoxy (EP) resin and Polyvinyl chloride (PVC)) and fibers (Glass Fiber (GF) and Carbon Fiber (CF)); among these the CF has the highest recycling energy consumption of 183–286 MJ/kg. The different types of processes used for the recycling of wind turbine blade are mechanical, thermal (pyrolysis and oxidation in fluidized bed) and chemical. The recycling energy consumption for mechanical processes are minimal (0.27/3.03 MJ/kg), whereas the same for chemical processes are highest (63–91 MJ/kg).
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Electrical energy storage systems are key to the integration of intermittent renewable energy technologies such as photovoltaic solar systems and wind turbines. As installed battery energy storage system capacities rise, it is crucial that the environmental impacts of these systems are also positive. In this work, a methodology to ascertain the effect and effectiveness of integration of energy storage on the carbon footprint of isolated island grid energy systems and its reduction is presented. Two metrics are introduced — the Levelized Emissions of Energy Supply (LEES), and the reduction in emissions per additional unit of energy storage (R). The proposed methodology is applied to an island grid scenario to ascertain the variation in the LEES value with the peak power and energy storage capacity of the BESS. A simplified LCA of a utility-scale Lithium-ion BESS is also carried out for this purpose. It is found that for the considered scenarios, incorporation of battery systems is always effective in reducing emissions, with a maximum possible reduction of nearly 50% compared to no storage. With the help of the metric R, the proposed methodology is also useful in identifying isolated energy systems which should be prioritized for incorporation of additional energy storage capacity.
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Recent calls by world leaders recommend that policy responses to the COVID crisis incorporate “green stimulus” or “green recovery” as a vital element. In a 2014 article in this journal, we argued that green stimulus would be an inefficient way to either boost demand and restore full employment in the context of the global financial crisis or pursue long-run environmental goals. In this paper, we argue that the attempt to marry green and COVID recovery programs may prove an even less fitting response to the near-term crisis, while still threatening to put environmental policy on paths that prove inefficient in the long run. We argue that green stimulus/recovery, while yielding more long-term climate benefits, would likely generate a slower and smaller recovery in jobs and activity than a traditional macroeconomic stimulus. This creates a trade-off for policymakers. The global financial crisis provides our primary real-world experience of green stimulus/recovery policies. A small but growing number of ex post empirical studies suggest that these measures' near-term growth impact was less than expected or obtained at a relatively high cost. There is also a danger that orienting green programs toward near-term shocks like the global financial crisis and COVID could compromise public understanding of, political support for, and the quality of environmental and climate policies in the long run. This article is categorized under: • Climate Economics > Economics of Mitigation Abstract Trade-offs are inescapable: the greener the stimulus, the weaker the recovery from COVID.
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Wind power produces more electricity than any other form of renewable energy in the United Kingdom (UK) and plays a key role in decarbonisation of the grid. Although wind energy is seen as a sustainable alternative to fossil fuels, there are still several environmental impacts associated with all stages of the lifecycle of a wind farm. This study determined the material composition for wind turbines for various sizes and designs and the prevalence of such turbines over time, to accurately quantify waste generation following wind turbine decommissioning in the UK. The end of life stage is becoming increasingly important as a rapid rise in installation rates suggests an equally rapid rise in decommissioning rates can be expected as wind turbines reach the end of their 20–25-year operational lifetime. Waste data analytics were applied in this study for the UK in 5-year intervals, stemming from 2000 to 2039. Current practices for end of life waste management procedures have been analysed to create baseline scenarios. These scenarios have been used to explore potential waste management mitigation options for various materials and components such as reuse, remanufacture, recycling, and heat recovery from incineration. Six scenarios were then developed based on these waste management options, which have demonstrated the significant environmental benefits of such practices through quantification of waste reduction and greenhouse gas (GHG) emissions savings. For the 2015–2019 time period, over 35 kilotonnes of waste are expected to be generated annually. Overall waste is expected to increase over time to more than 1200 kilotonnes annually by 2039. Concrete is expected to account for the majority of waste associated with wind turbine decommissioning initially due to foundations for onshore turbines accounting for approximately 80% of their total weight. By 2035–2039, steel waste is expected to account for almost 50% of overall waste due to the emergence of offshore turbines, the foundations of which are predominantly made of steel.
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The deployment of wind energy technologies is instrumental to support a sustainable energy transition. However, the manufacturing, operation and end-of-life management of wind turbines (WTs) entail the consumption of a significant amount of energy and material resources contributing to environmental impacts. Thus, much of the ongoing sustainability research on WTs have been concentrated on material innovation (e.g. substitution of rare earth elements in the generators) and technology innovation (e.g. new recycling technologies for blade composites) to increase resource security and efficiency. Nevertheless, there is a lack of research analysing the role circular business models (CBMs) can have in driving implementation of circular economy (CE) strategies for narrowing, slowing and closing resource loops in the wind industry. Accordingly, this paper summarises the key potential sustainability benefits related to 14 CBMs with application to the wind industry, including the main industrial challenges that should be overcome to facilitate the upscaling of sustainable CBMs and value chains. A description of how CBMs can be implemented to support the resource-efficient management of wind energy projects at different stages of development and operation is also provided with the aim of guiding CE-oriented decision-making processes.
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Performances of hybrid Natural Fiber-Reinforced Composites (NFRCs) from E-glass, Nacha (Hibiscus macranthus Hochst. Ex-A . Rich.), and Sisal (Agave sisalana) fibers are investigated for wind turbine blades applications. The process of composite manufacturing was getting started with harvesting and extracting the fibers from undesired constituents. To improve the interfacial interaction between fibers, it was further treated with 5% of NaOH and remnants removal. The experiment was performed based on the Taguchi method, specifically with L16 orthogonal array. Four levels of a natural fiber weight ratio (i.e. 5%, 10%, 15 %, and 20%) were considered during the composite preparations process while the weight of glass fiber was maintained at 5% and 10%. The composites are manufactured using the hand lay-up method, and the test specimens are as per American Society for Testing and Materials (ASTM) standards. Then, tensile, compressive, and flexural tests were carried out using a universal testing machine (UTM). Analysis of variance (ANOVA) was employed to determine the factors which affect the experimental responses. Hence, in the main effect, it was confirmed that Nacha fiber (%wt of N) significantly contributes to tensile, compressive, and flexural strength at a 95% level of confidence. Furthermore, the optimal fiber compositions of composites are determined based on a higher signal-to-noise ratio (S/N) for the corresponding strengths.
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Global wind energy is developing rapidly, with total installed capacity having increased from 24,332 MW in 2001 to 650,758 MW in 2019. Environmental concerns have been raised over the large volumes of waste that will be generated as these wind turbine blades are decommissioned over the coming decades. Although wind turbines are largely clean during operation, in manufacture and end-of-life stages they release emissions and consume significant energy. Wind turbine blades are mainly made from lightweight thermoset composites (glass fibre/carbon fibre), which are economically challenging to recycle. This study aims to understand the economic feasibilities of recycling technology options for blade waste management. We have used a quantitative method, first building a financial performance model for wind turbine blade end of life, then evaluating and comparing the financial performance for all available end of life options, and finally performing a sensitivity analysis. We found that mechanical recycling and fluidised-bed recycling are the optimal options of the ready-to-go technologies, and chemical recycling is the optimal option for technologies currently available only at lab scale.
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The growing use of fibre-reinforced polymer (FRP) composites and the increasing global generation of FRP waste implies an urgent need to develop a circular economy strategy to promote the recovery of fibres and the valorisation of resins. This review paper analyses the current scenario of FRP recycling technologies and evaluates the potentials of microwave-assisted heating as a technology to provide an intensification in terms of energy-efficiency, selective heating and processing speed, as well as an electrified thermal treatment for FRP recycling. The paper presents an overview of the estimated FRP production and waste generation per sector in the coming decennia and the current and envisioned international legislation related to the management of end-of-life FRP. The paper also discusses the strong and weak points of the existing FRP recycling technologies, their readiness level and overall environmental impact in terms of equivalent CO2 emissions. Furthermore, the emerging microwave-assisted FRP recycling technology is evaluated, showcasing the potentials and obstacles for its implementation and the potential end-use and characteristics of the recycled components. A literature survey on the existing prototypes, MW-assisted waste-to-value processes and reported energy demand is conducted. Finally, the required resources and framework for the consolidation of the MW-assisted FRP recycling as an alternative and economically viable technology are assessed.
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Wind turbines are becoming larger to produce more power from the wind in a given area. While the large-size wind turbines are advantageous in terms of generating power, the blades are very heavy and difficult to transport and install. General Electric Co. and the National Renewable Energy Laboratory proposed a new blade design and manufacturing concept that covers the blade with tensioned fabrics. This fabric-covered wind turbine blade is composed of spar-rib structures and covering fabric skins. The present study investigates the aerodynamic effects of fabric skin. A fluid–structure interaction (FSI) analysis was performed about the fabric skin of a large-sized fabric-covered blade. Through static and dynamic FSI analyses, the response of the fabric skin was analyzed according to the wind speeds. The natural frequencies and mode shapes were compared. It was confirmed that the tension of the fabric skin should be increased as much as possible to maintain aerodynamic efficiency, and in addition that the natural frequencies and mode shapes were changed by the wind speeds.
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Electricity generated from tidal streams via underwater turbines has significantly lower greenhouse gas emissions than fossil-fuel derived electricity. However, tidal stream turbine blades are conventionally manufactured from non-recyclable reinforced polymer composite materials. Tidal stream capacity is forecast to be over 1GW by 2030, which using current methods will ultimately produce around 6000 tonnes of non-recyclable blade waste. This waste is currently disposed of in landfill or incinerated, both of which have greenhouse gas and human health impacts. To address a growing waste management problem, this high-level study considers for the first time a range of conventional and bio-based materials, manufacturing methods, and end-of-life treatments to determine the blade materials and designs likely to have low environmental impact. A finite element model is used to develop material cases and Life Cycle Assessment is used to study the impacts of each over a ‘cradle to dock, dock to grave’ scope. The impact of material choices on cost and modifications to the wider turbine are considered. Compared to a glass fibre composite turbine blade, steel blades are around 2.5 times heavier, and incur additional environmental impact due to upgrades required to the wider turbine. Carbon fibre composite blades weigh less than glass fibre, but cause greenhouse 80% greater gas emissions, and human and ecosystem health risks, so are also not recommended. The best environmental performance of the cases considered was a flax fibre composite. This material offers greenhouse gas emissions around 50% lower than glass fibre materials when manufactured using conventional epoxy resin, and around 40% lower when manufactured using recyclable epoxy resin, which also enables the reuse of the fibre and may further reduce environmental impact. Initial results suggest that the cost of these materials are similar to or lower than conventional composite materials.
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Gasoline commonly contains several additives to enhance fuel efficiency. Knocking is the property related to the fuels' abnormal combustion in the internal combustion (detonation) engines. Additives are commonly added to gasoline to prevent knocking in the combustion chamber. This work provides novel octane hyperboosting phenomenon in isoolefinic hydrocarbons/ gasoline blends. Octane hyperboosting is characterized by the motor octane number (MON) of the mixtures, including isoolefinic hydrocarbons into motor gasoline. exceeding the MON of the individual components in that mixture. This finding counters the widely held assumption that interpolation between the MON values of a pure compound and the base fuel provides the bounds for the MON performance of the blend. This is clearly distinct from the more commonly observed synergistic blending of gasoline additives with gasoline, where the MON never exceeds the performance of the highest performing component. The results demonstrated that there was a nonlinear MON change phenomenon where a maximum MON of 50% isoolefinic hydrocarbons was greater than that of pure isoolefinic components. This phenomenon can be called “octane hyperboosting” Finally, this phenomenon also increases the potential candidate list of gasoline additives, as compounds hitherto discounted due to their lower pure component MON may exhibit hyperboosting behavior, and thereby enhanced performance, in blend.
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Fuel properties and engine efficiency represent the prime parameters developed by the transport technology, combustion science, and refining industry focused, all of them, to reduce local and global emissions from vehicles. To assist in making an initial down-selection of promising fuel blendstock candidates, it is useful to use a fuel “merit function.” This work proposes novel strategy technique to upgrade the fuel properties using merit function. Moreover, this function provided a simple tool to evaluate the potential thermal efficiency benefits of various fuels when multiple fuel properties or performance metrics are changing simultaneously. Merit function is a mathematical equation that link fuel properties to efficiency gains. Additionally, it includes research octane number (RON), octane sensitivity (S), heat of vaporization (HoV), laminar flame speed (SL), particulate matter index (PMI), catalyst light-off temperature (Tc,90). The merit function demonstrated that increasing RON and S provided the most straightforward pathway to increased efficiency. On average, the largest contributors to merit function score were RON, S, and HoV. The RON and S relate the potential efficiency improvements of the engine to the fuel’s resistance to autoignition for engine operating with high compression ratio.
Chapter
As the use of fossil fuels for energy production and in motor vehicles is gradually replaced by wind power, solar power, and electric cars, there is a corresponding increase in a newer form of waste – e-waste – and the chemical pollutants released from this waste. There is increasing evidence, from the effects on wildlife and from those involved in the recycling of this waste, that pollutants released from e-waste may be harmful.
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This review covers the recent advancements in selected emerging energy sectors, emphasising carbon emission neutrality and energy sustainability in the post-COVID-19 era. It benefited from the latest development reported in the Virtual Special Issue of ENERGY dedicated to the 6th International Conference on Low Carbon Asia and Beyond (ICLCA′20) and the 4th Sustainable Process Integration Laboratory Scientific Conference (SPIL′20). As nations bind together to tackle global climate change, one of the urgent needs is the energy sector's transition from fossil-fuel reliant to a more sustainable carbon-free solution. Recent progress shows that advancement in energy efficiency modelling of components and energy systems has greatly facilitated the development of more complex and efficient energy systems. The scope of energy system modelling can be based on temporal, spatial and technical resolutions. The emergence of novel materials such as MXene, metal-organic framework and flexible phase change materials have shown promising energy conversion efficiency. The integration of the internet of things (IoT) with an energy storage system and renewable energy supplies has led to the development of a smart energy system that effectively connects the power producer and end-users, thereby allowing more efficient management of energy flow and consumption. The future smart energy system has been redefined to include all energy sectors via a cross-sectoral integration approach, paving the way for the greater utilization of renewable energy. This review highlights that energy system efficiency and sustainability can be improved via innovations in smart energy systems, novel energy materials and low carbon technologies. Their impacts on the environment, resource availability and social well-being need to be holistically considered and supported by diverse solutions, in alignment with the sustainable development goal of Affordable and Clean Energy (SDG 7) and other related SDGs (1, 8, 9, 11,13,15 and 17), as put forth by the United Nations.
Article
The recycling of glass fibre thermoset composites in general and of wind turbine blades in particular has been investigated for many years but still remains challenging. In order to provide the reader with an overview of the challenges related to the end-of-life of wind turbine blades, this review first describes the chain of processes taking place when wind turbine blades end their service life. Key elements of this value chain are presented and discussed throughout the review. These include the estimation and prediction of the volume of wind turbine blade waste, the legislation and standards framing the processes of the value chain and the technical processes transforming wind turbine blades into new valuable materials and their applications. The review highlights the need of solutions addressing the entire value chain and ends with discussing the potentials of circular economy and life cycle engineering to facilitate the implementation of sustainable solutions. To provide a holistic picture of the sustainability of these solutions, the mechanisms of social acceptance and technology perception are also discussed.
Article
Zusammenfassung de Die Windenergie hat sich in den letzten Jahrzehnten zu einem wichtigen Pfeiler der Stromproduktion entwickelt. Ein modernes Rotorblatt besteht aus Kompositmaterialien, die mit Hilfe von unterschiedlichen Verarbeitungstechnologien aufgebaut werden. Als Rohstoffe kommen Glas- und Carbonfasern, Tränkharze, Kernmaterialien und Strukturklebstoffe zum Einsatz, anschließend werden mehrere Coatingsschichten aufgebracht. Kleinere Reparaturen der Rotorblätter können mit Hilfe von schnell verarbeitbaren Systemen vor Ort durchgeführt werden. Nach Ende der Lebensdauer sind Entsorgungs- und zunehmend Recyclingkonzepte in Richtung einer nachhaltigen Kreislaufwirtschaft erforderlich. Summary en Wind energy has become an important pillar of electricity production in recent decades. A modern rotor blade consists of composite materials that are built up using different processing technologies. Glass and carbon fibers, impregnating resins, core materials and structural adhesives are used as raw materials, followed by application of several coating layers. Minor repairs of a rotor blade can be carried out on site using fast-curing systems. At the end of their service life, increasingly recycling concepts are required to establish a sustainable circular economy.
Article
The limited literature on the cost of various recycling methodologies for thermoset composites sets the background of this work, focusing mainly on the identification of an upper and lower economic value of glass fibre recovered from wind turbine blades recycling. The study briefly reviews the materials used by various original equipment manufacturers (OEM) for wind turbine blades. Successively, it provides an overview of the various recycling methods with interest in recovered materials, mechanical and physical properties, which are used, for estimating a maximum expected value. All recycling processes show a negative effect on mechanical properties with strength loss between 30% and 60%. Process energy demands are reviewed, and considerations are set forward to estimate the minimum cost of operating mechanical, pyrolysis and fluidized bed plants in Germany. Ultimately, current applications of recovered material and related markets are explored. Through interviews and secondary data, it is highlighted that despite the lower mechanical properties, grinded material finds applications in traditional processes, cement kilns and new products. It is also found that pyrolysed fibres can be used as insulation material and oils can be easy to distil. Pyrolysis is a relatively expensive process, thereby, distillation of the oils and energy recovery are necessary enablers towards commercial viability. Mechanically grinded material presents the lowest process cost with ca. €90/tonne, thus, below landfilling and incineration and falling within the attention of private businesses. Numerous markets are available for recovered materials from wind turbine blades, primarily for grinded products and secondly for pyrolysed glass fibre.
Article
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The so-called 20-20-20 targets for the European Union include a reduction in greenhouse gas emissions by 20% compared to 1990, 20% of primary energy from renewables, and a 20% reduction in primary energy demand through energy efficiency by 2020. Wind energy has played and will continue to play a significant role in progress towards meeting these goals; in 2012 it accounted for around 7% of total European electricity consumption. Against the background of the recent trend towards ever larger wind turbines at higher hub heights, this contribution explores the challenges to and prospects for a continued up-sizing of wind turbines in the future. Based on a literature review and interviews with experts in the European wind industry, the key challenges for large onshore wind turbines are identified and qualitatively analyzed in a European context. Further developments of large wind turbines depend on several components and related challenges rather than just one. The main challenges are thought to be related to social acceptance, the logistics of transport and erection, and the medium term sustainability of the political and economic support for wind energy. It seems likely that social acceptance will center around the issue of aerodynamic noise and the allowed distance from the turbine, although further research is required to fully understand the public perception of especially large wind power plants. In addition, the sheer size of larger wind turbines in the future presents significant challenges in terms of the materials and structures employed. There is little consensus on the likely development of drive train technologies, though a slight tendency towards direct drive systems with permanent magnet generators as well as multi-stage gearboxes was encountered, which could also serve to improve reliability. For the rotor blades, a trend towards fully carbon fiber blades is expected, and towers will continue to be constructed from steel and/or concrete, albeit both of these components increasingly in the form a modular construction.
Article
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Rising demand for fibre reinforced polymer composite material and environmental issues necessitates resource efficient use of manufacturing and end of life composite waste. The impact of such sustainability or recycling initiatives can be limited and misguided if the global/national picture is not thoroughly considered. This problem is addressed in this paper with the aid of new Sankey diagrams generated from virgin material and waste volumes in the UK. Environmental footprints of virgin material and recycling were used to explore the resource benefits of composite re-manufacturing. The use of Sankey diagrams enables better decision making with respect to targeting sustainability effort.
Article
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Fiber-reinforced polymer composites are engineered materials commonly used for many structural applications because of the high strength-to-weight and stiffness-to-weight ratios. Although the service life of these materials in various applications is usually between 15 and 20 years, these often keep the physical properties beyond this time. Recycling composites using chemical, mechanical, and thermal processing is reviewed in this article. In this review of carbon, aramide, and glass fiber composites, we provide, as of 2011, a complete view of each composite recycling technology, highlight the possible energy requirements, explain the product outputs of recycling, and discuss the quality (fiber strength) of recyclates and how each recyclate fiber could be used in the market for sustainable composite manufacturing. This article also includes the new concept of 'direct structural composite recycling' and the use of these products in the same or different applications as low-cost composite materials after small modifications.
Article
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Wind turbines with a rated power of 5 to 6 MW are now being designed and installed, mostly for offshore operation. Within the EU supported UpWind research project, the barriers for a further increase of size, up to 20 MW, are considered. These wind turbines are expected to have a rotor diameter up to 250 m and a hub height of more than 150 m. Initially, the theoretical implications of upscaling to such sizes on the weight and loads of the wind turbines are examined, where it is shown that unfavourable increases in weight and load will have to be addressed. Following that, empirical models of the increase in weight cost and loads as a function of scale are derived, based on historical trends. These include the effects of both scale and technology advancements, resulting in more favourable scaling laws, indicating that technology breakthroughs are prerequisites for further upscaling in a cost-efficient way. Finally, a theoretical framework for optimal design of large wind turbines is developed. This is based on a life cycle cost approach, with the introduction of generic models for the costs, as functions of the design parameters and using basic upscaling laws adjusted for technology improvement effects. The optimal concept or concepts is obtained as the one that minimizes the total expected costs per megawatt hour (levelized production costs). Copyright © 2011 John Wiley & Sons, Ltd.
Article
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Electric generation by wind turbine is growing very strongly. However, the environmental impact of wind energy is still a matter of controversy. This paper uses Life Cycle Assessment, comparing two systems: a 4.5MW and a 250W wind turbines, to evaluate their environmental impact. All stages of life cycle (manufacturing, transports, installation, maintenance, disassembly and disposal) have been analysed and sensitivity tests have been performed. According to the indexes (PEPBT (primary energy pay back time), CO2 emissions, etc.), the results show that wind energy is an excellent environmental solution provided first, the turbines are high efficiency ones and implemented on sites where the wind resource is good, second, components transportation should not spend too much energy and, third, recycling during decommissioning should be performed correctly. This study proves that wind energy should become one of the best ways to mitigate climate change and to provide electricity in rural zones not connected to the grid.
Article
The wind power industry is growing rapidly. Wind turbines (WTs) are perceived as a low environmental impact energy generation technology. While the service life of a WT is relatively long (20-40 years), at some point a significant number of WTs will reach the end of their service lives. To recover maximum value from these WTs, planning for the end-of-service life of wind turbines (EOSLWTs) is paramount. Historically, environmental life cycle assessments of WTs have often only considered the materials extraction and processing, manufacturing, and use phases, leaving the management of EOSLWTs outside the scope of their attention. Four key EOSLWTs issues that are essential for the continuing development of wind energy technologies are presented: i) The challenges of managing of EOSLWTs given the fast growth rate of the industry and the large number of existing installed WTs; ii) The EOSLWT alternatives such as remanufacturing and recycling to recover functional and material value respectively; iii) The critical activities in the WT reverse supply chain such as recovery methods, logistics of transportation, quality of returns, and quality of reprocessed WTs; and iv) The economic and business issues associated with EOSLWTs. It is expected that the discussion provided will stimulate a dialog among decision makers and raise awareness of economic opportunities and unanticipated challenges in the wind power industry.
Article
Stella Job, Knowledge Exchange Expert for the Materials Knowledge Transfer Network (KTN), UK, discusses the issues surrounding the recycling of glass fibre reinforced plastics (GRP), and reviews some of the options available today.
Article
The main concept currently in use in wind energy involves horizontal-axis wind turbines with blades of fiber composite materials. This turbine concept is expected to remain as the major provider of wind power in the foreseeable future. However, turbine sizes are increasing, and installation offshore means that wind turbines will be exposed to more demanding environmental conditions. Many challenges are posed by the use of fiber composites in increasingly large blades and increasingly hostile environments. Among these are achieving adequate stiffness to prevent excessive blade deflection, preventing buckling failure, ensuring adequate fatigue life under variable wind loading combined with gravitational loading, and minimizing the occurrence and consequences of production defects. A major challenge is to develop cost-effective ways to ensure that production defects do not cause unacceptable reductions in equipment strength and lifetime, given that inspection of large wind power structures is often problematic.
Article
WITH A BOOMING WIND ENERGY INDUSTRY, DRIVING THE DEVELOPMENT OF LARGER AND LARGER TURBINES, THE QUESTION IS NOW ARISING OF HOW TO DEAL WITH WIND TURBINES AT THE END OF THEIR LIFECYCLE, AND PARTICULARLY THOSE WIND TURBINE BLADES MADE OF HARD-TO-RECYCLE COMPOSITES. RENEWABLE ENERGY FOCUS' KARI LARSEN INVESTIGATES POSSIBLE ROUTES FOR THE RECYCLING OF WIND TURBINE BLADES.
Article
This model intends to provide projections of the impact on cost from changes in economic indicators such as the Gross Domestic Product and Producer Price Index.
Article
Although wind technology produces no emissions during operation, there is an environmental impact associated with the wind turbine during the entire life cycle of the plant, from production to dismantling. A life cycle assessment is carried out to quantify the environmental impact of two existing wind turbines, a 1.8 MW-gearless turbine and a 2.0 MW turbine with gearbox. Both technologies will be compared by means of material usage, carbon dioxide emissions and energy payback time based on the cumulative energy requirements for a 20 year life period. For a quantitative analysis of the material and energy balances over the entire life cycle, the simulation software GEMIS® (Global Emission Model of Integrated System) is used.The results show, as expected, that the largest energy requirement contribution is derived mainly from the manufacturing phase, representing 84.4% of the total life cycle, and particularly from the tower construction which accounts for 55% of the total turbine production. The average energy payback time for both turbines is found to be 7 months and the emissions 9 gCO2/kWh. Different scenarios regarding operation performance, recycling of materials and different manufacturing countries such as Germany, Denmark and China are analysed and the energy payback time and carbon dioxide values obtained. Finally, the wind energy plant is compared with other renewable and non-renewable sources of energy to conclude that wind energy is among the cleanest sources of energy available nowadays.
Article
The technologies for recycling thermoset composite materials are reviewed. Mechanical recycling techniques involve the use of grinding techniques to comminute the scrap material and produce recyclate products in different size ranges suitable for reuse as fillers or partial reinforcement in new composite material. Thermal recycling processes involve the use of heat to break the scrap composite down and a range of processes are described in which there are various degrees of energy and material recovery. The prospects for commercially successful composites recycling operations are considered and a new initiative within the European composites industry to stimulate recycling is described.
Article
Life cycle assessment is a technique to assess environmental aspects associated with a product or process by identifying energy, materials, and emissions over its life cycle. The energy analysis includes four stages of a life cycle: material production phase, manufacturing phase, use phase, and end-of-life phase. In this study, the life cycle energy of fiber-reinforced composites manufactured by using the pultrusion process was analyzed. For more widespread use of composites, it is critical to estimate how much energy is consumed during the lifetime of the composites compared to other materials. In particular, we evaluated a potential for composite materials to save energy in automotive applications. A hybrid model, which combines process analysis with economic input–output analysis, was used to capture both direct and indirect energy consumption of the pultrusion process in the material production and manufacturing stages.
Article
Both environmental and economic factors have driven the development of recycling routes for the increasing amount of carbon fibre reinforced polymer (CFRP) waste generated. This paper presents a review of the current status and outlook of CFRP recycling operations, focusing on state-of-the-art fibre reclamation and re-manufacturing processes, and on the commercialisation and potential applications of recycled products. It is shown that several recycling and re-manufacturing processes are reaching a mature stage, with implementations at commercial scales in operation, production of recycled CFRPs having competitive structural performances, and demonstrator components having been manufactured. The major challenges for the sound establishment of a CFRP recycling industry and the development of markets for the recyclates are summarised; the potential for introducing recycled CFRPs in structural components is discussed, and likely promising applications are investigated.
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