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Energy poverty and greenhouse gas emissions (GHGs) are two major challenges on the road to sustainable development goals. The main goal of the global policy is to combat GHGs and energy poverty through the transition from fossil fuels to clean and renewable sources. Empirical research with a global or regional focus can offer practical implications for the development of global energy and environmental policies. To this end, this paper estimates the impact of electricity from different sources on energy poverty and GHGs in low-, middle- and high-income countries with annual data. The paper firstly performs the generalized method of moments and the sequential estimation of a linear panel-data model. According to the findings, (i) electricity from coal contributes to the increase in GHGs in the upper-middle income countries but does not have a significant effect on energy poverty. (ii) The effect of electricity from natural gas and nuclear energy on GHGs and energy poverty is mixed. Electricity from nuclear power is confirmed to have a reducing effect on energy poverty in middle and low-income countries. However, it does not have a significant effect in high-income countries. (iii) Electricity from renewable and hydro sources makes a significant contribution to reducing GHGs and energy poverty. (iv) Finally, heterogeneous estimates for robustness check greatly support baseline findings. • Examines the impact of electricity from renewable and non-renewable sources on energy poverty and GHGs in 92 countries. • GMM and SELPDM dynamic panel data estimators are employed. • Electricity from coal is an unsustainable option in tackling energy poverty and GHGs. • The effects of electricity from nuclear and natural gas are controversial. • Electricity from renewable sources is an option that supports Win-Win status. [ABSTRACT FROM AUTHOR]

Currently, most district heating networks in China are running in the heat-setting mode, which limits the adjustments of combined heat and power (CHP) units. By considering the electrical power system and district heating system together, the peak regulatory capabilities of CHP units can be improved, and renewable energy accommodation can be promoted. In this paper, a tractable integrated heat and electricity dispatch (IHED) model is described that addresses the thermal inertia characteristics of pipelines and buildings to increase flexibility. A water mass method (WMM) for pipeline thermal inertias is proposed to simplify the IHED model by removing the integer variables and differential equations. Benefiting from the WMM, the proposed IHED model is a single-level nonlinear model that is tractable. An efficient iterative algorithm based on the generalized Benders decomposition and a sequential approach combined with the iterative algorithm and Interior Point OPTimizer (IPOPT) are proposed to solve the IHED model. The WMM is tested in thermal inertia simulations compared to an existing node method (NM) and commercial simulation software. The proposed solution strategy is verified in a small-scale system and a practical system. The simulation results are discussed to demonstrate the feasibility and economy of the IHED model proposed here. • A water mass method (WMM) for pipeline thermal dynamics is proposed. • An integrated heat and electricity dispatch (IHED) model considering thermal dynamics is proposed. • A decomposition method and an efficient iterative algorithm are proposed to solve IHED. • A sequential approach combined with iterative algorithm and IPOPT is proposed to improve the optimality of the solution. • The WMM is tested in the simulations compared to an existing node method (NM) and a commercial simulation software. [ABSTRACT FROM AUTHOR]

Abstract Recent electricity management systems such as Smart Grids and Virtual Power Plants help to better integrate distributed generation renewable resources (RDG), such as photovoltaic, small hydro or micro wind in electricity markets. In this context, an important increase of small-scale power generation technologies is expected in Spain by 2020, according to the Spanish Action Plan for Renewable Energy. This paper analyses the environmental and economic impacts of the massive integration of RDG in Spain for 2020 by using an Input-Output approach. The induced production and employment effects in every sector due to new RDG project investments as well as the CO 2 reductions attributed to a decline in conventional electricity consumption are estimated. The results indicate that investments in RDG based on photovoltaic and small-hydro have the greatest impact on employment generation. The RDG investments will lead to a decrease in emissions of 21.67% in 2020 compared with 2013. The RDG technologies become an alternative to reach a sustainable economic growth in Spain. In future research, a multi-regional input-output model and the study of the links between energy consumption, standard of living and consumption patterns will aid to delve deeper into the relationship between economic growth and the environmental impacts of small-scale renewable technologies. Highlights • RDG will be over half of total installed electricity generation capacity in 2020. • The impact of RDG deployment is quantified on Spanish economy in 2020. • The IO methodology is used to study the environmental and economic impacts. • Photovoltaic and small-hydro have the highest impact on employment generation. • RDG becomes an alternative to reach a sustainable economic growth in Spain. [ABSTRACT FROM AUTHOR]

Abstract Although renewables in the resource-rich countries of the Middle East and North Africa (MENA) are inconsequential contributors to regional total primary energy supply, recent project developments and overt support from a range of influential regional actors suggest a general trend towards a more environmentally sustainable electricity supply. This trend is driven just as much by economics as other factors, as rapidly falling renewable energy capital costs are complementing favourable policy environments, technical suitability, and concerns around the impacts of anthropogenic climate change and local pollution. Finance is an especially important consideration in this transition, yet it receives insufficient coverage. This paper seeks to remedy this deficiency of academic inquiry by highlighting the case of the Gulf Cooperation Council (GCC) to draw out broader implications for the region. We outline the factors that affect the financeability of projects, review the latest developments in renewable energy finance in the region, and present policy recommendations going forward. Graphical abstract Image Highlights • Renewable energy finance plays a critical role in reducing GCC renewable energy costs. • An overview of critical drivers of renewable energy finance is presented. • Three case studies in the GCC are used to draw out implications for MENA as a whole. • We provide recommendations for encouraging regional renewables finance. [ABSTRACT FROM AUTHOR]

Abstract Energy system integration can bring several benefits to energy systems, notably to those that are in transition to high shares of renewable energy. Strategies are needed to realize the theoretical benefits of this approach in practice. Therefore, this paper proposes the organization and mathematical formulation of a multi-carrier day-ahead market in which electricity, gas and heat are traded simultaneously. This market set-up is applied to a conceptual test case to identify how - compared to a reference set-up mimicking the current practice - the multi-carrier market is able to unlock the benefits of energy system integration. It is quantitatively shown that the multi-carrier market (1) eliminates the need for forecasts of prices on subsequent markets and the consequences of the related errors, (2) allows to use the flexibility available in one carrier to facilitate the balancing in another, e.g. using the flexibility of a heat system to help balance the electricity system, and (3) enables specific market outcomes, unachievable in a sequential set-up, which increase the optimality of the market outcome. Highlights • Consistent multi energy market design solves many energy transition challenges. • Simultaneous clearing of different markets results in an increased social welfare. • Simultaneous clearing of different markets reduces the need for price forecasting. • A policy to facilitate integration of heat and electricity market is to be devised. • Measures to increase the liquidity on DA gas and heat markets should be brought. [ABSTRACT FROM AUTHOR]

Abstract The Brazilian electricity system is an important example of a large country relying on a high renewable energy matrix with a major focus on hydropower, which has historically allowed for low carbon electricity production. However, the increase in the demand and climate change impacts on the availability of these renewable resources represent important challenges for long-term power planning. The contribution of this paper is twofold: Firstly, a first attempt to use the EnergyPLAN model for the analysis of the Brazilian electricity sector and in particular to study future scenarios is presented. Secondly, the possibility of achieving a 100% RES system is also addressed. The 100% RES scenario is found to be theoretically possible but a substantial increase in the overall installed capacity would be required, to support the grid mainly during the spring and summer season. The results underline the importance of seasonal complementarity of hydro and wind power and reveal how an increase in RES would add exportation potential, reducing also the Brazilian external energy dependency. The study identifies risk factors for these high RES scenarios and outlines several avenues for future research to address cost, environmental and technical uncertainties of the system. Highlights • The Brazilian power sector is analysed with EnergyPLAN computer model. • Renewable scenarios are compared for technical, cost, emissions and risk parameters. • The importance of seasonal complementarity of hydro and wind power is outlined. • The 100% RES scenario results in full decarbonization of the system at higher cost. • The 100% RES scenario results in higher exportation and lower importation potential. [ABSTRACT FROM AUTHOR]

Several influential energy systems models indicate that renewable energy must provide a significant share of the world's electricity to limit global temperature rises to below 2 °C this century. To better represent the costs and other implications of this shift, it is important that these models realistically characterise the technical and economic potential of renewable energy technologies. Towards this goal, this paper presents the first temporally-explicit Geospatial Information System (GIS) methodology to characterise the global onshore wind energy potential with respect to topographical features, land use and environmental constraints. The approach combines the hourly NASA MERRA-2 global wind speed data set with the spatially-resolved DTU Global Wind Atlas. This yields high resolution global capacity factors for onshore wind, binned into seasonal and diurnal time-slices to capture the important temporal variability. For each country, the wind power generation capacity available for various capacity factor ranges is produced, and made freely available to the community. This data set can be used to assess the economically viable wind energy potential on a global or per-country basis, and as an input to various energy systems models. [ABSTRACT FROM AUTHOR]

Distributed energy resources DERs are small scale energy system which could provide local supply when placed at customers' premises. They aggregate multiple local and diffuse production installations, consumer facilities, storage facilities and monitoring tools and demand management. The main challenges when assessing the performance of an off-grid hybrid micro-grid system HMGS are the reliability of the system, the cost of electricity production and the operation environmental impact. Hence the tradeoff between three conflicting objectives makes the design of an optimal HMGS seen as a multi-objective optimization task. In this paper, we consider the optimization and the assessment of a HMGS in different Swedish cities to point out the potential of each location for HMGS investment. The HMGS consists of photovoltaic panels, wind turbines, diesel generator and battery storage. The HMGS model was simulated under one-year weather conditions data. A multi objective particle swarm optimization is used to find the optimal system configuration and the optimal component size for each location. An energy management system is applied to manage the operation of the different component of the system when feeding the load. The techno economics analysis shows the potential of HMGS in the Swedish rural development. [ABSTRACT FROM AUTHOR]

Renewable energy has the characteristics of wide distribution, sustainable use and low impact on the environment, which is suitable for application and promotion in the island area. Given the concerns about wind and PV curtailment of energy-rich islands, it is potentially a good idea to export extra renewable energy to the mainland. The aim of this paper is to investigate the economic viability of transforming renewable energy into exportable electricity or hydrogen. A comprehensive renewable energy system model is developed based on the P-graph to simulate an energy system, which integrates electricity, heat and hydrogen on a virtual island. Solar, wind, wave and biomass are the main renewable energy sources in the developed energy system. The objective includes the construction cost, operating cost, and also environmental cost, which is related to the greenhouse gas footprint. Findings from the case study show that extra renewable energy exporting by electricity is cheaper than using hydrogen for the studied island, and the optimal dispatch structure can deliver 51 GWh of electricity annually for 292 M CNY (about 42 M EUR). A sensitivity analysis of export prices and renewable energy uncertainty verifies the economics of electricity export. [Display omitted] • Evaluating the economic benefit of exporting excess renewable energy from islands. • Both the electricity and heating demands of the island are taken into account. • The hydrogen can be exported and used for cogeneration in fuel cells. • Exporting electricity is more economical in the case of island. [ABSTRACT FROM AUTHOR]

Some benefits of spot electricity markets integration include the optimization of renewable power, increasing transmission grid security and the decreasing need for internal generation reserves. The high penetration of wind power is known to have a clear influence on price convergence between electricity markets joined by market splitting. However, in multiple interconnected markets, cross-border flows can also play a role in the market splitting behaviour. Denmark, with a high penetration of wind power, is clearly the ideal case study. This paper aims to assess the influence of high penetration of wind power on the market splitting behaviour between West and East Denmark, taking into account cross-border electricity flows. This is modelled through logit and non-parametric models, estimating the probability of market splitting occurrence between both Danish bidding areas. Market splitting probability is found to be sensitive to wind power, nevertheless with distinct behaviour according to interconnection congestion configuration. The highest availability of wind power in West Denmark, which can reach a generation share of 1.5 times the demand, requires strong cross-border interconnections to allow the export of the excess generation. Policies governing a joint assessment of the requirements for additional interconnection and wind power expansion plans, should be developed. [ABSTRACT FROM AUTHOR]

The common process in all applications of a salinity-gradient solar pond (SGSP) is the energy extraction process using single-phase mode heat transfer with some limitations such as pumping the large amount of mass flow rate, and need for big size of heat exchanger. In every respect, two-phase mode heat transfer can be selected as an advantage due to its passive case of operation and comparatively high heat transfer capacity with rational system size. In this paper, an enhanced design of a large scale SGSP power plant using some two-phase closed thermosyphons has been simulated and compared with the single-phase mode heat transfer. The simulation results showed that the overall thermal efficiency of the solar pond power plant was the highest using both thermosyphons and heat exchangers. [ABSTRACT FROM AUTHOR]

Solar pond has been a reliable supply of heat source for industrial process that requires heat at the temperature <100 °C. In this paper, the prospect of solar pond in generating electricity has been explored with the aid of using TEGs (thermoelectric generators) for converting the heat available at LCZ (lower convective zone) into electricity. By using the transient heat transfer model developed and the testing result of a thermoelectric module, this study has covered the potential of generating electricity for the solar pond operates in the climate of Group A, B, and C under Köppen climate classification. The effect of heat extraction, climatic variation, temperature polarisation, and the conversion efficiency of TEG on the thermal performance and electrical performance of the system has been discussed. The solar pond operates in Riyadh (Group B of Köppen climate classification) possesses the highest potential in generating electricity, which is about 4.834 kWh/year-m 2 at heat extraction of 15% of year average horizontal solar radiation (i.e. solar pond yearly efficiency of 15%) while having average LCZ temperature of 80 °C throughout the year. Overall, the thermal-electrical conversion efficiency, η t of this system is in the range of 1%–1.5% from the heat extracted. [ABSTRACT FROM AUTHOR]

Ever-increasing price of conventional energy resources and related environmental concern enforced to explore alternative energy sources. Inherent uncertainty of power generation and demand being strongly influenced by the electricity market has posed severe challenges for DRPs (Demand Response Programs). Definitely, the success of such uncertain energy systems under new market structures is critically decided by the advancement of innovative technical and financial tools. Recent exponential growth of DG (distributed generations) demanded both the grid reliability and financial cost–benefits analysis for deregulated electricity market stakeholders. Based on the SGT (signaling game theory), the paper presents a novel user-aware demand-management approach where the price are colligated with grid condition uncertainties to manage the peak residential loads. The degree of information disturbances are considered as a key factor for evaluating electricity bidding mechanisms in the presence of independent multi-generation resources and price-elastic demand. A correlation between the cost–benefit price and variable reliability of grid is established under uncertain generation and demand conditions. Impacts of the strategies on load shape, benefit of customers and the reduction of energy consumption are inspected and compared with Time-of-Used based DRPs. Simulation results show that the proposed DRP can significantly reduce or even eliminate peak-hour energy consumption, leading to a substantial raise of revenues with 18% increase in the load reduction and a considerable improvement in system reliability is evidenced. [ABSTRACT FROM AUTHOR]

Economic models are needed to analyze the impact of policies adopted for controlling carbon emissions and increasing distributed renewable generation in microgrids (green penetration). The impacts are manifested in performance measures like emissions, electricity prices, and electricity consumption. This paper presents an economic model comprising bi-level optimization and Pareto analysis. In the bi-level framework, the upper level models the operation of the microgrids and the lower level deals with electricity dispatch in the grid. The economic model is applied on a sample network in two steps. In step1, the bi-level model yields operational strategies for the microgrids and the corresponding values of the grid performance measures. In step2, a statistical analysis of variance combined with Pareto optimization attains guidelines for setting policies for emissions reduction and green penetration without adversely impacting electricity prices and demand. We conclude that renewable generation from microgrids can significantly reduce the negative impacts of the policies. Our economic model is novel as it 1) integrates operational strategies of microgrids and the grid under an emissions control regime, 2) explicitly considers social cost of carbon in the electricity dispatch, and 3) balances multiple objectives of emissions reduction, green penetration, and electricity consumption using a Pareto analysis. [ABSTRACT FROM AUTHOR]

Worldwide, renewable electricity projects are granted production support to ensure competitiveness. Depending on the design of these support schemes, the cash inflows to investment projects will be more or less exposed to fluctuations in electricity and/or subsidy prices. Furthermore, as renewable electricity technologies mature, there is a possibility that the current support scheme will be terminated or revised in ways that make it less generous or more in line with market mechanism. Using a real options approach, we examine how investors in power projects respond to such market and policy risks. We show that: (1) due to price diversification, the differences in market risk between support schemes like tradeable green certificates, feed-in premiums and feed-in tariffs are less than commonly believed; (2) the prospects of termination will slow down investments if it is retroactively applied, but speed up investments if it is not; and, (3) this policy uncertainty may add a substantial risk to investments, especially in the first case where investors expect future curtailment of subsidies to affect new and old installations alike. We conclude the paper by discussing the division of risk between investor and government. [ABSTRACT FROM AUTHOR]

Abstract: NZEB (Net zero energy building) is regarded as an integrated solution to address problems of energy-saving, environmental protection, and CO2 emission reduction in the building section. NZEB could be even possible with electricity production if enough renewable energy could be used. Moreover, various building-service systems with renewable energy sources have been widely considered for potential applications in NZEB. All of these new features extend the technical boundary of the conventional energy-efficient buildings, attach a more profound implication to the sustainable development of building technology, and therefore pose a challenge to evaluation works on NZEB performance. This paper presents a guided tour on NZEB evaluation through literature-research. An overview about definitions and energy-efficient measures of NZEB is presented so that the research object and technology boundary can be clarified for NZEB evaluation. Then, a summary of widely-used research method, tool and performance indicator in evaluation is provided for the methodology part. This part also includes a discussion on the application of LCA (life cycle assessment) in NZEB evaluation and LCA's role in promoting a well-defined NZEB. Finally, potential progress in NZEB evaluation with possible development trends is highlighted in terms of energy storage, load match and smart grid. [Copyright &y& Elsevier]

Abstract: One of the main reasons attributed to the slow uptake of grid-connected residential PV (photovoltaic) systems, is the lack of information about the near-term economic benefits which are as important as long-term viability for residential customers. This paper presents a comparative assessment of the near-term economic benefits of grid-connected residential PV systems. Case studies from the UK and India are taken as examples, as they vary significantly in solar resource, customer demands, electricity prices and financial support mechanisms. A metric termed PEUC (prosumer electricity unit cost) is proposed to develop an economic evaluation methodology to assess the near-term benefits from PV systems. The results obtained showed that, under the present financial support mechanisms, domestic PV systems provide near-term economic benefits in most locations in India. For most locations in the UK, cost reduction is needed to achieve near-term financial benefits and this varies depending on the location of installation. The results presented demonstrate the importance of location specific system planning and demand-generation matching through optimal sizing of the PV system and demand side management. [Copyright &y& Elsevier]

Abstract: The article presents the main design features and photovoltaic requirements of a FPCS (floating photovoltaic cover system) for water irrigation reservoirs whose purpose is to reduce the evaporation of water while generating electrical power. Also, a summary of installation costs and relationship with the yield performance is deeply analyzed. A prototype of 20 kWp was implemented, and given the success of the results observed, the whole surface reservoir was covered (4490 m2 and 300 kWp). The paper analyses the first electricity productions of the system and from these data the CO2 balance of the facility is calculated. [Copyright &y& Elsevier]

Abstract: The various forms of solar energy – solar heat, solar photovoltaic, solar thermal electricity, and solar fuels offer a clean, climate-friendly, very abundant and in-exhaustive energy resource to mankind. Solar power is the conversion of sunlight into electricity, either directly using photovoltaic (PV), or indirectly using concentrated solar power (CSP). The research has been underway since very beginning for the development of an affordable, in-exhaustive and clean solar energy technology for longer term benefits. This paper, therefore, reviews the progress made in solar power generation research and development since its inception. Attempts are also made to highlight the current and future issues involved in the generation of quality and reliable solar power technology for future applications. A list of 121 research publications on the subject is also appended for a quick reference. [Copyright &y& Elsevier]

Abstract: There is a potential to utilize a significant amount of renewable energy in Sweden and European union (EU). Biomass can fulfil some 8500–12,500 TW h/y in EU, while the total utilization was 16,084 TW h/y 2009. Even though there is a significant amount of wind power, hydro power and potentially also solar power, it still is most economical to reduce the consumption of heat, electricity and fuels for vehicles. A saved kWh is normally cheaper than to produce one extra. In this paper different opportunities for saving energy will be discussed. This includes manufacturing industries, process industries, power plants and energy systems including distribution of power and smart grids, food production and transportation. There is also a major potential to save energy in buildings, both in the north where it is cold, and in the south where it can be very hot summer time. Here the potential is to avoid cooling instead. Technical solutions as well as economic incentives are covered. Environmental aspects are addressed, so that the solutions will be long term sustainable. [Copyright &y& Elsevier]

Abstract: The European Union has established challenging targets for the share of renewable energies to be achieved by 2020; for Spain, 20% of the final energy consumption must be from renewable sources at such time. The aim of this paper is the analysis of the consequences for the electricity sector (in terms of excess cost of electricity, investment requirements, land occupation, CO2 emissions and overcapacity of conventional power) of several possibilities to comply with the desired targets. Scenarios are created from different hypotheses for energy demand, biofuel share in final energy in transport, contribution of renewables for heating and cooling, renewable electricity generation (generation mix, deployment rate, learning curves, land availability) and conventional power generation (lifetime of current installations, committed deployment, fossil fuel costs and CO2 emissions cost). A key input in the estimations presented is the technical potential and the cost of electricity from renewable sources, which have been estimated in previous, detailed studies by the present authors using a methodology based on a GIS (Geographical Information System) and high resolution meteorological data. Depending on the scenario, the attainment of the targets will lead to an increase in the cost of electricity from 19% to 37% with respect to 2007. [Copyright &y& Elsevier]

Abstract: The reduction of CO2 emissions linked with human activities (mainly energy services and transport), together with the increased use of renewable energies, remain high priorities on various political agendas. However, considering the increased consumption of energy services (especially electricity), and the stochastic nature of some of the most promising renewable energies (wind for instance), the challenge is to find the optimal mix of technologies that will provide the energy services, without increasing the CO2 emissions, but nonetheless ensuring reliability of supply. The focus of this paper is to present the DESDOP tool, based on mixed integer linear optimisation technics, that helps giving insight in the optimal mix of technologies that will simultaneously help decrease the emissions while at the same time guarantee resilience of supply. The results show that while it is not yet possible to avoid electricity from the grid completely (hence nuclear or fossil fuel), CO2 reductions up to 20%, at no extra costs compared to the business-as-usual case, are easily achievable. [Copyright &y& Elsevier]

This study aims to analyse whether the Australian commitment to the Paris Agreement in 2016 and national energy policies will have a visible effect in decreasing the historical dependence of the NEM (National Electricity Market) on fossil fuels by 2030 and consequently decreasing the carbon emissions generated. In this paper, we model the 2030 electricity mix in the NEM in Australia. EnergyPlan , which is the modelling tool adopted for this study, is described and a reference model is conceived and calibrated based on the 2018 electricity situation on the NEM. The simulations are implemented considering three different supply scenarios and three potential electricity demands, to evaluate how different variables can influence the NEM electricity mix by 2030. This study concludes that by 2030 wind and solar power (including rooftop-PV systems) will be the major renewable energy contributors in the NEM, as opposed to 2018 where hydropower represented the main renewable energy source. Nonetheless, the electricity system in 2030 will continue to rely on fossil fuels, which will account for more than 50% of the final energy mix in every scenario, depicting that new efforts will still be needed beyond 2030. • We foresee the electricity mix in Australia by 2030. • We study three generation and three demand scenarios. • Fossil fuels will still account for more than 50% of the final electricity mix. • We expect a visible CO2 emissions reduction, due to the bet in RES in recent years. [ABSTRACT FROM AUTHOR]

Finland has recently adopted a high profile in climate change mitigation. Finland has declared a national target of achieving carbon neutrality by 2035. As a part of this, the use of coal for energy purposes has been banned from year 2029 onwards. The Finnish electricity system is already very low-carbon, and more wind and nuclear power is being constructed. However, District heating (DH) is a backbone of the Finnish energy system, and it is still quite reliant on fossil fuels and domestic high-emission fuel peat, their share being 51% of DH fuels in 2018. This paper models the impacts of this transition on the electricity markets and DH systems and develops scenarios with a large-scale transition to wind and nuclear power and heat pumps in DH systems. The study finds that large-scale introduction of heat pumps would be profitable in cities Helsinki, Espoo, Turku and Vantaa, especially with the planned decrease of electricity tax. The study indicates that the impacts on Winter time capacity adequacy could be managed, but this requires considerable increases in nuclear and wind capacity. • Finland abandons hard coal use by 2029 as part of achieving carbon neutrality. • Increasing wind and nuclear power mitigates electricity price increase and capacity deficit. • Heat pumps can provide alternative to coal-CHP. • Electricity distribution fee and tax limit economic potential of heat pumps. [ABSTRACT FROM AUTHOR]

This paper presents a transition approach for markets with high-share renewables to connect the delivery of physical medium and long-term market contracts with daily system operation while ensuring safe and reliable grid operation given the under-developed electricity market environment in China. The proposed approach decomposes the market contracts into daily energy schedules with rolling updates of subsequent daily schedules to ensure fairness in contract delivery, then employs security-constrained economic dispatch to allocate the decomposed energy to each power plant to determine the day-ahead schedules. In the security check, a multi-section coordinating strategy is incorporated to maximize the utilization of transmission capacity and determine the optimal power flow. Results of the Yunnan case study demonstrate the feasibility and effectiveness of the proposed approach in modeling the day-ahead schedules and handling the multiple objectives and numerous constraints, and therefore provide a reference for similar hydro-dominated systems in transitioning to electricity spot markets. Finally, discussions and suggestions are proposed to promote electricity markets further. • An approach connecting physical contracts with daily generation schedules is proposed. • The approach is verified to be feasible and effective in the Yunnan electricity market. • The Yunnan case study provides a reference for similar systems transitioning to spot markets. • Discussions and suggestions are proposed to promote electricity markets. [ABSTRACT FROM AUTHOR]

Although several studies have recognized the challenges brought about the high integration of Renewable Energy Sources (RES), research has yet to systematically investigate the effects of different levels of Energy Efficiency Measures (EEMs) on power systems with a high share of RES. The primary aim of this paper is to quantitatively evaluate the economic impact of different levels of energy efficiency investments in systems with a high share of RES, based on the case of Brazil. Our review analysis revealed a lack of understanding of how to calculate the Long-term Average Cost of Saved Electricity (LACoSE). Therefore, the methodological contribution of this research also lies in the proposition of a step-by-step procedure to estimate this variable. Findings of this study suggest that EEMs may result in a reduction in the expected new installed capacity between 1.9% and 10.3%, and from 0.4% to 4.3% for the total CO 2 emissions (for reductions in the final electricity demand varying from 1% to 5% respectively). This comes with a decrease in the overall system costs between 1.9% and 7.7%. The results provide further support for the hypothesis that the economic impacts of energy efficiency investments and its cost-effectiveness are affected by the share of RES in the power system and these type of measures may provide holistic benefits including not only economic advantages but also environmental and social improvements. The proposed methodology largely extends beyond the case addressed as it may provide valuable lessons for other electricity systems. • Cost-effectiveness of energy efficiency measures is assessed for a renewable system. • A methodology is proposed to calculate the Long-term Average Cost of Saved Electricity (LACoSE). • The economic benefits are positive for the power system evaluated. • Results are not highly influenced by the estimated LACoSE. • Findings would support the development of effective energy efficiency policies. [ABSTRACT FROM AUTHOR]