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Abstract: This paper presents a technical assessment of wind power potential for seven locations in Jordan using statistical analysis to determine the wind characteristic based on the measured wind data. Rayleigh distribution is used to model the monthly average data and used to estimate the wind power in the selected locations. Energy calculations, capacity factors and cost of wind energy production were determined for the selected locations with wind machines of different sizes ranging between 1.65 MW and 3 MW. The quantitative estimates of the technical and economic potential are presented graphically. Rayleigh parameter is adjusted to the hub height using one seventh power law to estimate the power output of the machine. The energy cost analyses show that all selected sites have high economic potential with unit cost less than $0.04/kWh of electricity. The lowest unit cost per kWh is obtained by using GE 2.5 MW at Tafila site. Finally, the results of this study reveal that Jordan has high potential wind energy and its environmental and energy policy targets can be met by exploitation wind energy. [Copyright &y& Elsevier]

Abstract: Over the centuries, energy has been supplied by wood, coal, oil and natural gas, as well as by uranium. All these energy sources are limited and create pollution problems. This has led countries to focus on a sustainable and cleaner energy sources. Wind energy is rapidly emerging as one of the most cost-effective forms of renewable energy with very significant increases in annual installed capacity around the world. In this paper, authors have tried to review the current state of wind power utilization in Ethiopia. First, a brief overview is given on the Ethiopian electric power sector in order to gain insight into the main energy sources of the country and installed electric power capacities. Wind energy potential and current energy policy in Ethiopia were discussed respectively in the subsequent sections. Finally, short reviews of the ongoing and planned wind energy together with other renewable energy projects are given. Ethiopia, a country that relies on hydroelectric plants for the bulk of its power, is now developing significant wind energy capacities. Lack of reliable wind data covering the entire country has been one of the reasons for limited application of wind energy in Ethiopia, but recently studies have shown that Ethiopia has substantial potential to generate electricity from wind, geothermal and hydropower. Considering the substantial wind resource in the country, the government has committed itself to generate power from wind plants by constructing eight wind farms with total capacities of 1116MW together with a number of hydropower plants over the five year Growth and Transformation Plan (GTP) period from 2011 to 2015. This development of wind power is a part of the current energy sector policy of the country that aims at a five-fold increase in renewable energy production by the end of 2015. [Copyright &y& Elsevier]

Abstract: It is highly significant for China to improve its development of wind power. In order to promote the sustainable development, a more comprehensive evaluation of factors affecting the effectiveness of investment in the industry wind power is required to be conducted to formulate a relatively stable policy supporting mechanism for the development of wind power. Based on the green accounting framework, this paper evaluates a typical wind power project from economic, environment and energy alternative respects comprehensively. We simulate the main factors influencing cost and benefit of the wind power investment with the Monte Carlo method. Finally, we discuss how to promote wind power with respect to the concern of government, investors and environmentalists. [Copyright &y& Elsevier]

Abstract: China’s wind industry has grown rapidly over the past decade. Continued growth in this industry is critical for China’s domestic energy security and the global environment. However, little is known about the microeconomic drivers that move wind energy development in China. Based on a survey of experts in Mainland China and Hong Kong Special Administrative Region, this paper finds that the most important drivers of wind energy investment in China are perceived to be those that can have an immediate impact on a wind energy developer’s cash flow: government financial assistance, easy and inexpensive transmission access, wind energy cost decline, and a high feed-in-tariff. A renewable portfolio standard, tax incentives and international research and development cooperation are seen as less important. These findings underscore the importance of reducing the financial risk in wind energy development. However, none of the key drivers is directly tied to energy output, which suggests that China’s wind energy policies must be modified to incentivize energy output, rather than just installed capacity. [Copyright &y& Elsevier]

Abstract: Over the last decade there has been a rapid global increase in wind power stimulated by energy and climate policies. However, as wind power is inherently variable and stochastic over a range of time scales, additional system balancing is required to ensure system reliability and stability. This paper reviews the technical, policy and market challenges to achieving ambitious wind power penetration targets in Ireland’s All-Island Grid and examines a number of measures proposed to address these challenges. Current government policy in Ireland is to address these challenges with additional grid reinforcement, interconnection and open-cycle gas plant. More recently smart grid combined with demand side management and electric vehicles have also been presented as options to mitigate the variability of wind power. In addition, the transmission system operators have developed wind farm specific grid codes requiring improved turbine controls and wind power forecasting techniques. [Copyright &y& Elsevier]

Abstract: With regard to energy conservation and the reduction of emissions, China is dedicated to facilitating the development of renewable energy in order to fulfil its international responsibility. In recent years, the installed wind power capacity in China has increased rapidly due to its large scale and centralization. The high penetration of wind power has brought about a series of problems such as the wind energy utilization and curtailment, auxiliary services and the pricing mechanism. The resolution of these problems needs policies which will provide more support than the current technologies and standards for wind power. This paper takes the evaluation of capability of accepting large-scale wind power in China as its object of study. According to the analysis of such risk factors as the influence of the grid on wind power integration, wind power itself, the market and policy, an evaluation model of the ability of accepting large-scale wind power is established based on risk theory. Then, the estimation of the ability to accept wind power in Gansu Province is used to testify to the effectiveness of this model. Finally, a series of reasonable policies for wind power are proposed. [Copyright &y& Elsevier]

Abstract: Wind energy development is booming worldwide with Germany and the United States being forerunners in installed capacity. Based on a review of relevant laws and regulations, policy, siting, and permitting documents, academic literature, and expert interviews, the paper compares the permit and environmental impact assessment (IA) policies and regulations pertaining to wind energy projects in both countries. The focus is on the potential of IAs in supporting an environmentally conscious development of wind power generation. This includes the analysis of IA regulations on the project level, strategic level impact assessment and planning processes, opportunities for public involvement and transparency of processes, and the clarity and predictability of the IA provisions. The findings suggest certain variations between both countries'' permit and IA processes for wind energy projects and further research needs, inter alia on the actual effects of strategic assessment of wind development on subsequent permitting. [Copyright &y& Elsevier]

Abstract: Turkey is a rich country from the point of variety and potential of renewable energy resources. Hydros, winds, biomass, solar and geothermal are important renewable and environmentally friendly sources for energy in Turkey. Turkey produces large amount of hydropower with a total gross hydropower potential of 433TWh/yr, which is equal to 13.8% of the total hydropower potential of Europe. Technically useable potential is 216TWh/yr and economic potential is 140TWh/yr. The main aim of the present study is to investigate hydropower potential of Turkey and small hydropower plants in Eastern Black Sea Region for sustainable energy development in Turkey. The geography of Turkey especially, Eastern Black Sea Region supports and suitable the development of the small hydro plants to increase the energy generation and utilization of available water sources in Turkey. Besides, the paper deals with hydropower policies to meet ever increasing energy demand for sustainable development of Turkey. [Copyright &y& Elsevier]

Abstract: The growth of the renewable energy sector in the world in the first decade of the twenty-first century was rapid. Wind energy sector was one of the fastest growing renewable energy technologies. In this paper, authors have tried to review the current state of wind power utilization in Serbia as one of the most penetrating RES technologies in the world. The brief overview of electric power sector in Serbia was given in order to describe the environment for emerging wind energy sector development. Sufficient wind energy resources were identified in several regions of the country. Current energy policy in Serbia was reviewed in terms of the regulations that have to be followed in order to meet the requirements for RES power plants, i.e. wind power plant construction. In subsequent section short reviews of wind energy projects which are in their initial phases are provided. The wind energy sector in Serbia is emerging despite the difficulties faced by the investors, regulatory bodies and other shareholders, in the course of the past several years. There is an urgent need of a broader transfer of specific knowledge and technologies related to wind farms and wind turbines in order to speed up the current wind energy sector development. [Copyright &y& Elsevier]

Abstract: Energy is an essential ingredient of socio-economic development and economic growth. Many countries frequently held meetings and discussions has energy agenda. These countries are working to balance energy demand and supply. Renewable energy technology is one of the solutions, which produces energy by transforming natural phenomena into useful energy forms. Wind energy is a reliable and promising renewable energy. Wind energy becomes more and more attractive as one of the clean renewable energy resources. The installed capacity of electricity generation from wind energy is rapidly increasing in many countries and these countries are implementing variety incentive policies. Therefore, the importance of wind energy is expected to increase much more in the coming decades. The presented study comprehensively reviews wind energy in terms of three aspects, namely status, potential and policies analyses and assessments, for the first time to the best of the author''s knowledge. This review paper covers the status, potential and policies of the wind energy, the issues faced, and the latest research. Also, the current situation, potential and development of the increasing are discussed. This study is presented recommendations for increasing the installed capacity of wind power. [Copyright &y& Elsevier]

Abstract: Promotion of renewable energy sources is a widely adopted policy since they are accepted to positively contribute to ensure the security of energy supply, mitigate CO2 emissions and meet the increasing energy demand. In parallel with that global thought, wind energy has been a hot topic in Turkish energy agenda although the share of wind energy in total energy resources of the country is still low. In this framework, the policies and applications regarding wind energy in Turkey are examined, the short-term and long-term priorities are evaluated and some suggestions are provided in this paper. [Copyright &y& Elsevier]

Abstract: The intensity of market penetration and hence the relevance of clean energy technologies in mitigating climate change will greatly depend on their cost-effectiveness. This paper discusses the economic and policy aspects of speeding up the market of these technologies to reach cost parity. A combination of historical energy market dynamics, technology diffusion and endogenous learning models were employed in the analyses. Starting from giving a preferential position to emerging renewable energy technologies in the energy and climate policy, which also means securing adequate financial resources for their deployment, could lead in the base scenario to a full-cost breakthrough of wind power around 2027 and of photovoltaics in 2032. The combined global market share of renewable electricity in 2050 could reach 62% of all electricity (now 19%) of which wind and solar power alone could account for almost two-thirds corresponding to a carbon saving in the range of 8–16 GtCO2. However, if the new technologies were downgraded in the energy and climate policy context, the combined impact of solar and wind could remain at no less than 11% which would marginalize these technologies in the fight against climate change. The estimates for financial support to achieve cost parity were very sensitive to the assumptions of the input parameters: in the base case the extra costs or learning investments for solar power were €1432 billion and for wind power €327 billion, but with more conservative input data these values could grow manifold. On the other hand, considering the potentially cheaper electricity from new technologies above the cost parity point and putting a price on carbon could result in a positive yield from public support instead of it being regarded merely as unnecessary spending. The findings stress the necessity of long-term policies and strong commercialization strategies to bring the new energy technologies to breakeven point, but also highlight the complexity of assessing the true costs of making new energy technologies fully competitive. [Copyright &y& Elsevier]

Abstract: Wind power has a significant contribution to make in efforts to abate CO2 emissions from global energy systems. Currently, wind power generation costs are approaching parity with costs attributed to conventional, carbon-based sources of energy but the economic advantage still rests decidedly with conventional sources. Therefore, there is an imperative to ensure that wind power projects are developed in the most economically optimal fashion. For wind power project developers, shaving a few tenths of a cent off of the kilowatts per hour cost of wind power can mean the difference between a commercially viable project and a non-starter. For civic authorities who are responsible for managing municipally supported wind power projects, optimizing the economics of such projects can attenuate stakeholder opposition. This paper attempts to contribute to a better understanding of how to economically optimise wind power projects by conflating research from the fields of energy economics, wind power engineering, aerodynamics, geography and climate science to identify critical factors that influence the economic optimization of wind power projects. [Copyright &y& Elsevier]

Abstract: Recent years have seen growing academic interest in the concept of induced diffusion as efforts to address concerns about energy security and climate change have intensified. Research on induced diffusion explores whether policy tools or interventions can incentivise the diffusion of innovations. This body of literature has explored the effectiveness and efficiency of various policy interventions and as such has been mainly concerned with the determinants of diffusion. This paper is, by way of contrast, concerned with the patterns of diffusion when diffusion is induced. Drawing on the Bass and Davies models of innovation diffusion we develop a number of propositions that suggest that the patterns of diffusion are different when policy plays a role in the diffusion process. These propositions are then econometrically tested in the context of the international diffusion of wind energy in 25 OECD countries. We find that, as predicted, without effective and strong policy interventions, countries will have conventional logistic diffusion with very similar speeds of diffusion. However, as expected the patterns of diffusion take on a different functional form (Bass curve) when there is a strong policy inducement. We conclude by discussing the implications and limitations of these results and suggesting avenues for further research. [Copyright &y& Elsevier]

Abstract: This paper investigates available offshore wind energy resources in China’s exclusive economic zone (EEZ) with the aid of a Geographical Information System (GIS), which allows the influence of technical, spatial and economic constraints on offshore wind resources being reflected in a continuous space. Geospatial supply curves and spatial distribution of levelised production cost (LPC) are developed, which provide information on the available potential of offshore wind energy at or below a given cost, and its corresponding geographical locations. The GIS-based models also reflect the impacts of each spatial constraint as well as various scenarios of spatial constraints on marginal production costs of offshore wind energy. Furthermore, the impacts of differing Feed-in-tariff (FIT) standards on the economic potential are calculated. It confirms that economic potential of offshore wind energy could contribute to 56%, 46% and 42% of the coastal region’s total electricity demands in 2010, 2020 and 2030. The shallow waters along the coasts of Fujian, Zhejiang, Shanghai, Jiangsu and northern Guangdong are identified as suitable areas for developing offshore wind energy in terms of wind resources and economic costs. However, the influence of tropical cyclone risks on these regions and detailed assessments at regional or local scale are worth of further discussions. Nevertheless, the models and results provide a foundation for a more comprehensive regional planning framework that would address additional infrastructure, planning and policy issues. [Copyright &y& Elsevier]

Abstract: Municipalities around the world are using community energy plans (CEPs) to drive progress towards a more sustainable energy future. Many recognize the supply of local and renewable energy as a crucial component of a resilient future including the potential use of wind power generation. The city of Guelph (Ontario, Canada) included wind energy as a component of its CEP. The goal of this work was to estimate the potential for wind power generation within the municipal boundaries of this city. This paper summarizes the methodology used and results obtained with site and meteorological data, wind maps, and turbine power curves. The methodology relies on the use of a geographically uniform array of turbines, spread throughout the community. An array of utility-scale turbines could potentially generate 29% of Guelph’s 2005 total electricity demand, whereas one consisting of small-scale turbines could achieve 10% of that demand. [ABSTRACT FROM AUTHOR]

Abstract: This paper provides an assessment of the commercialization potential for high altitude wind power (HWP). Several technological and policy barriers are identified that may affect the development and deployment of the technology in the US. Technical barriers include electrical transmission from high altitudes and the development of viable methods of energy storage to address intermittency. Non-technical barriers include the lack of a carbon price in the US, which provides an advantage to embedded technologies and widens the ‘valley of death.’ A variety of stakeholders are analyzed in order to understand potential impacts upon the development of HWP. Many fossil fuel producers and utility companies have been leveraging political authority to lobby against a carbon tax, which could be crucial for broad deployment of renewable energy technologies. The combination of technical and non-technical barriers indicates that commercialization of HWP is unlikely in the short term. Commercialization would require major policy shifts at the federal level and advances in S&T. Recommendations are provided to increase federal investment in applied research through additional funding for the Advanced Research Projects Agency—Energy (ARPA-E). It is also recommended that ARPA-E create a matching fund to assist in the commercialization of renewable energy technologies. [Copyright &y& Elsevier]

Abstract: Although wind power is currently enjoying a boom period, maximizing development potential will be largely influenced by how well developers manage social and environmental issues. As more wind farms are developed, threats to both social and ecological endowments will increase. The intent of this paper is to provide a comprehensive literature review and analysis of social impediments to wind power development under two broad thematic areas—concerns over impairment of existing community endowments and concerns over impairment of existing ecosystems—in order to provide policy makers with insight into strategic approaches for reducing the propensity for social opposition to wind power development projects. [Copyright &y& Elsevier]

Abstract: A widely accepted premise regarding wind power development policy is that implementation of economic policy instruments, which are designed to close the cost gap between wind power and entrenched fossil fuel power generation technologies, will significantly catalyze enhanced levels of wind power development activity. This paper contests this premise by arguing that non-economic barriers to wind power development have the capacity to significantly inhibit wind power development in industrialized nations despite the implementation of economic policy instruments. Forces which deter wind power development in four economically advanced economies that exhibit phlegmatic progress in wind power development – Australia, Canada, Japan and Taiwan – are identified and amalgamated into a STEP framework describing social, technical, economic and political forces that inhibit wind power development. The conclusions of this analysis are twofold. First, failure to mitigate these STEP forces may undermine the efficacy of any given economic policy instrument that aims to close the cost gap between wind power and entrenched generation technologies. Second, attempts to mitigate these impediments might represent a way to achieve better policy results with less government financial commitment. [Copyright &y& Elsevier]

Abstract: Indian wind energy sector has seen a CAGR of more than 27% during the period 2002–2007. However, the annual capacity additions has been declining for the past 2 years and recently, India lost one place in the Global ranking on total installed wind capacity to China. While issues like unfavourable tariff, non-uniform state policies, unavailability of evacuation infrastructure, etc. can be attributed to the slower pace of capacity addition, the issue of unavailability of on-shore wind sites with sufficiently high wind velocity is expected to take centre stage in the next 2–3 years. Wind sites with low wind velocity make the investment unattractive to developers. Given the current situation, repowering as an investment option, which has already seen favourable response in countries like Germany and Denmark, would start maturing in India. This paper analyzes the present situation of the wind energy in India, evaluates the different wind energy market segments including repowering market, provides financial highlights of the repowering concept and ends with concluding remarks on major triggers which can set this concept in motion. [Copyright &y& Elsevier]

Abstract: This case study, which analyzes wind power development policy in Taiwan, investigates a theme that is commonly encountered by policy makers in a number of policy settings—how can appropriate policies be developed when two (or more) seemingly valid, yet disparate scientific or technical estimates confound objective analysis? The paper adopts the context of wind power development policy in Taiwan to demonstrate how to employ organizational analysis to identify factors which influence subjective assumptions underpinning disparate estimates of wind power potential and then demonstrates the application of two concepts from chaos theory – fitness landscapes and strategic real options – for guiding policy making despite the existence of technological dissent. In contrast to progressively declining feed-in tariffs that are commonly associated with fledgling renewable energy programs, this study introduces the concept of progressively escalating feed-in tariffs to encourage the development of mature markets—in this case, the Taiwan wind power market. [Copyright &y& Elsevier]

Abstract: Oman relies on gas and oil resources fuels for almost all of its energy needs. Almost 99% of its power generation is based on natural gas. However, the country''s natural gas supplies are currently largely committed, and it may become a net importer soon. Therefore, there is a need to look for alternative energy resources. This paper presents a review of the assessed potential of renewable resources and practical limitations to their considerable use in the perspective of present scenarios and future projections of the national energy for Oman. Solar and wind are likely to play an important role in the future energy in Oman provided that clear policies are established by the higher authority for using renewable energy resources. Rural Areas Electric Company has initiated solar and wind pilot projects in its concession area to confirm the performance and efficiency of renewable technologies in local conditions. [Copyright &y& Elsevier]

Abstract: This paper presents measurement system and detailed analysis of power quality at the substation of two different wind farm sites which are of low and high power rate. Measurement system has been designed using a data acquisition board (DAQ), Labview software, Matlab programming and a portable PC. The system has been installed at medium voltage level at substation of both wind farms. The real measurement results at substations are compared to current regulations in Turkey. [Copyright &y& Elsevier]

Abstract: Wind power in China registered a record level of expansion recently, and has doubled its total capacity every year since 2004. Many experts believe that China will be central to the future of the global wind energy market. Consequently, the growth pattern of wind power in China may be crucial to the further development of the global wind market. This paper firstly presented an overview of wind energy potential in China and reviewed the national wind power development course in detail. Based on the installed wind capacity in China over the past 18 years and the technical potential of wind energy resources, the growth pattern was modeled in this study for the purpose of prospect analysis, in order to obtain projections concerning the development potential. The future perspectives of wind energy development in China are predicted and analyzed. This study provides a comprehensive overview of the current status of wind power in China and some insights into the prospects of China''s wind power market, which is emerging as a new superpower in the global wind industry. [Copyright &y& Elsevier]

Abstract: A consensus has long existed within the electric utility sector of the United States that renewable electricity generators such as wind and solar are unreliable and intermittent to a degree that they will never be able to contribute significantly to electric utility supply or provide baseload power. This paper asks three interconnected questions: [1.] What do energy experts really think about renewables in the United States? [2.] To what degree are conventional baseload units reliable? [3.] Is intermittency a justifiable reason to reject renewable electricity resources? To provide at least a few answers, the author conducted 62 formal, semi-structured interviews at 45 different institutions including electric utilities, regulatory agencies, interest groups, energy systems manufacturers, nonprofit organizations, energy consulting firms, universities, national laboratories, and state institutions in the United States. In addition, an extensive literature review of government reports, technical briefs, and journal articles was conducted to understand how other countries have dealt with (or failed to deal with) the intermittent nature of renewable resources around the world. It was concluded that the intermittency of renewables can be predicted, managed, and mitigated, and that the current technical barriers are mainly due to the social, political, and practical inertia of the traditional electricity generation system. [Copyright &y& Elsevier]

Abstract: A hydrogen economy could offer energy stability, economical, and environmental benefits. In this paper, a hydrogen system based on wind-generated electricity is presented as a viable component in a hydrogen transition strategy. The strengths of a wind-hydrogen system are exhibited in its modular design, exploitation of existing technology, and utilization of a renewable resource. Specifically, a state level assessment of wind power was conducted in order to determine the ability of individual states to meet light-duty vehicle hydrogen fueling demands while utilizing the proposed system. Additionally, analysis related to existing hydrogen resources is presented in order to form a transition scenario. [Copyright &y& Elsevier]

Abstract: Academics, practitioners, and policy makers continue to debate the benefits and costs of alternative sources of energy. Environmental and economic concerns have yet to be fully reconciled. One view is that decisions that incorporate both society''s concern with the environment and investors’ desire for shareholder value maximization are more likely to be truly sustainable. We coin the term dual sustainability to mean the achievement of environmental and financial sustainability simultaneously. Many experts believe that wind energy can help to meet society''s needs without harming future generations. It is clean and renewable. Because the fuel is free it provides the ultimate in energy independence. Wind energy has emerged as a leading prospect, in part, because it is considered by many to be environmentally sustainable. However, a key question that remains is whether wind energy is financially sustainable without the extensive government support that has helped to create and nurture this growth industry. Using reliable, proprietary data from field research, our analysis employs a capital budgeting framework to evaluate the financial economics of investments in wind energy. We find that because of the convergence of improved technology, greater efficiency, and with the increasing cost of traditional, competing sources such as oil and natural gas, wind energy is close to becoming self-sustaining financially without the extensive federal government support that exists today. Wind energy can provide the best of both worlds. It is sustainable from an environmental perspective and it is becoming sustainable financially. In short, those companies investing in wind energy will be able to do well by doing good. Perhaps the achievement of dual sustainability is true sustainability. Our research findings and dual sustainability have several interesting and important implications for public policy towards wind energy. All imply that public policy can now be executed in a more effective and efficient manner. In the paper we outline and offer these better and cheaper public policy alternatives for consideration. [Copyright &y& Elsevier]

Abstract: This paper analyzes the success of wind energy in Spain from 1986 to 2007. Certain special characteristics have emerged in Spain that provide credibility to the feed-in tariff (FIT) device to promote this energy source. To explain this success, the analysis will focus on the intrinsic characteristics of FIT using the concepts of the transaction cost theory (TCE). Nevertheless, in this framework, special attention is placed on the role that specific political and institutional factors have played in providing stability to this instrument. Thanks to an early start and an on-going and generous FIT device, wind energy promotion for electricity has become a political success story in Spain. The main implication of this analysis is that this success is mainly due to the trade-off between stability and flexibility in the use of Spanish FIT. [Copyright &y& Elsevier]

As more distributed energy resources are deployed on electric grid systems across the world, it is important to identify, characterize, and quantify the value elements of different types of distributed energy resources so that policymakers, developers, and utilities can make informed energy deployment decisions. This paper focuses on the value of wind energy as a distributed energy resource (i.e., "distributed wind"). Because of a lack of distributed wind-specific valuation studies, in this review we document the current state of distributed energy resource valuation, analyze a wide array of distributed energy resource valuation metastudies, and identify several value elements for which we recommend developing more robust and standardized calculation methodologies for their potential inclusion in distributed wind valuation. These value elements are ancillary services and locational, resilience, reliability, and resource diversity benefits. This work lays the foundation for a future comprehensive framework for distributed wind valuation studies. • Detailed review of current state of DER valuation. • First specific examination of valuation of wind as a distributed energy resource. • Identification of important value elements for distributed wind valuation. [ABSTRACT FROM AUTHOR]

Distributed energy storage is a solution for increasing self-consumption of variable renewable energy such as solar and wind energy at the end user site. Small-scale energy storage systems can be centrally coordinated by "aggregation" to offer different services to the grid, such as operational flexibility and peak shaving. This paper shows how centralized coordination vs. distributed operation of residential electricity storage (home batteries) could affect the savings of owners. A hybrid method is applied to model the operation of solar photovoltaic (PV) and battery energy storage for a typical UK householder, linked with a whole-system power system model to account for long-term energy transitions. Based on results, electricity consumers can accumulate greater savings under centralized coordination by between 4 and 8% when operating no technology, by 3-11% with electricity storage alone, by 2-5% with stand-alone solar PV, while 0-2% with PV-battery combined. Centralized coordination of home batteries offers more optimized electricity prices in the system, and as such, higher private savings to all consumers. However, consumers without onsite energy technologies benefit more than PV-battery owners. Therefore, based on system-level benefits of aggregation, the regulator should incentivize prosumers with PV-battery, who are able to balance their electricity supply-demand even without central coordination, to let their storage be controlled centrally. Possible revenues of storage owners from ancillary services as well as the cost of aggregation (e.g., transaction fees charged by aggregators) are not considered in this analysis. • Centralized coordination vs. distributed operation of residential solar PV-battery is discussed. • Centralized coordination offers greater savings to prosumers, especially, under time of use tariffs. • Value of home batteries is dependent on the need for flexibility in the energy system in long term. • Consumers without battery benefit from the impact of "storage coordination" on power prices, more than battery owners themselves. • Private benefits of storage aggregation drops by 20% if aggregated storage devices increase five-fold. [ABSTRACT FROM AUTHOR]

Non-stationary renewable energy consumption can be permanently affected by supply, demand and policy shocks, and in this case renewable energy promoting policies can be implemented effectively. It is therefore important to determine which type of renewable energy is stationary. To this end, we introduce a new wavelet-based unit root test which takes into account the smooth structural changes and frequency components in the series. With this method we investigate the stationary of the renewable energy consumption for the US over the period 1973m01-2019m09. To compare the results, we also use conventional ADF and wavelet-based ADF unit root tests that do not take into account structural breaks. The findings of the wavelet-based Fourier ADF unit root test indicate that biofuels energy consumption is stationary, while geothermal, waste, and wind energy consumption are non-stationary. Furthermore, the findings of the wavelet-based ADF unit root test indicate that while hydropower energy consumption is stationary at levels, solar, wood, total biomass, and total renewable energy consumption contain a unit root. Overall, we conclude that renewable energy policies implemented in the US have permanent effects on seven types of renewable energy consumption, whereas these policies have temporary effects on hydropower and biofuels energy consumption. • The paper proposed a new wavelet-based unit root test with Smooth Structural Shifts. • The permanency of shocks on disaggregated renewable energy consumption was investigated. • Nine types of renewable energy consumption data was used. • The shocks have permanent effects on renewable energy consumption except hydropower and wind. [ABSTRACT FROM AUTHOR]