Capacity Value of Solar Power: Report of the IEEE PES Task Force on Capacity Value of Solar Power

This paper reviews methods used for adequacy risk assessment considering solar power, and for assessment of the capacity value of solar power. The properties of solar power are described as seen from the perspective of the balancing authority, comparing differences in energy availability and capacity factors with those of wind. Methodology for risk calculations considering variable generation (VG) are then surveyed, including the probability background, statistical estimation approaches, and capacity value metrics. Issues in incorporating VG in capacity markets are described, followed by a review of applied studies considering solar power. Finally, recommendations for further research will be presented

Hot August Nights: California’s Quest for Resource Adequacy Solutions to Promote Integration of Renewables and Energy Storage in the Midst of Climate Change-Related Challenges to Reliability

This Article focuses on the CPUC RA program’s role in helping to keep the lights (and air conditioning) on while advancing California’s continued mission to decarbonize the grid, even in the face of extreme climate-change induced weather events. It explains how the existing RA program creates risks of overestimating the availability of some capacity, including solar, wind, and energy storage resources, to meet demand in the increasingly critical evening hours. These risks are attributable to the program’s original design, which assumed that all resources will be available to meet load in all hours. This Article outlines the major CPUC regulatory developments since August 2020, aimed at reforming the foundation of RA to better plan and account for the availability limitations inherent in the rapidly shifting electricity resource mix that is necessary to meet California’s ambitious clean energy goals. In sum, this Article demonstrates how the pathway to a zero-carbon future in California is inextricably linked to the successful development and implementation of a reformed RA capacity paradigm that properly ensures procurement of resources capable of meeting both gross peak demand and energy requirements across all hours. Absent these key features, reliability will suffer, and accelerated decarbonization will almost certainly face major roadblocks. Part II provides background on RA in California. Part III describes some of the main components of California’s existing RA program. Part IV explains the main factors underlying the critical need for RA reform in California, including how integration of renewables and energy storage uniquely affects the existing structure. Part V introduces the future of RA in California: the CPUC’s newly reformed “24-hour slice of day” RA framework that will be implemented beginning with a test year in 2024 and will pave the way for a fully decarbonized, reliable grid. Finally, Part VI briefly concludes

Federal Regulatory Barriers to Grid-Deployed Energy Storage

Until recently, the most advanced form of grid-deployed energy storage involved pumping water up a hill. But “newer storage technologies like flywheels and chemical batteries have recently achieved technological maturity and are well into successful pilot stages and, in some cases, commercial operation”. If widely adopted these new energy storage technologies will fundamentally alter the operation of our electricity syste

The role of distribution network operators in promoting cost-effective distributed generation: Lessons from the United States for Europe

We explore the different competitive mechanisms applied by electric utilities from the USA in promoting cost-effective Distribution Generation (DG) resources and the challenges that they face due to the increase in DG connections. Case studies from California, Oregon, Colorado and New York are discussed. The case studies refer to two kinds of competitive mechanisms: Request for Proposals (RFP) and auctions (Renewable Auction Mechanism). The study proposes an auction design with a focus on the UK context and examines the role of energy regulators in auction mechanisms. We think that the experience described in the four case studies can be replicated by Distribution System Operators (DSOs) in Europe, however unbundling rules established in the EC third package need to be taken into consideration

The Final Hurdle?: Security of supply, the Capacity Mechanism and the role of interconnectors

The UK Government has developed a carefully designed Capacity Mechanism to ensure security of supply in the GB electricity system. This paper criticises the methods used to determine the amount of capacity to procure, and argues that the amount finally proposed is likely to be excessive, particularly (but not exclusively) in ignoring the contribution from interconnectors. More broadly, there has been too little attention to either the political economy, or the option value aspects. Procuring too little is risky, but fear of'the lights going out' can easily become a catch-all argument for excessive procurement, and associated subsidy. The risk of over-procurement, particularly of new capacity on long-term contracts, is that it drives up the costs to consumers; undermines renewable energy by transferring capped resources from renewable to fossil fuel producers; and impedes the Single Market including by weakening the business case for future interconnectors. The paper argues that the development of technologies and markets, particularly on the demand- side and of potentially available – 'latent' – capacity - further lowers the risks and increases options. This implies greater potential to defer more capacity procurement – and enhances the value of a more appropriate treatment of interconnectors in security assessments

The Final Hurdle?: Security of supply, the Capacity Mechanism and the role of interconnectors

The UK Government has developed a carefully designed Capacity Mechanism to ensure security of supply in the GB electricity system. This paper criticises the methods used to determine the amount of capacity to procure, and argues that the amount finally proposed is likely to be excessive, particularly (but not exclusively) in ignoring the contribution from interconnectors. More broadly, there has been too little attention to either the political economy, or the option value aspects. Procuring too little is risky, but fear of'the lights going out' can easily become a catch-all argument for excessive procurement, and associated subsidy. The risk of over-procurement, particularly of new capacity on long-term contracts, is that it drives up the costs to consumers; undermines renewable energy by transferring capped resources from renewable to fossil fuel producers; and impedes the Single Market including by weakening the business case for future interconnectors. The paper argues that the development of technologies and markets, particularly on the demand- side and of potentially available – 'latent' – capacity - further lowers the risks and increases options. This implies greater potential to defer more capacity procurement – and enhances the value of a more appropriate treatment of interconnectors in security assessments

Hydropower\u27s Promise: The Opportunities and Challenges of Hydropower for Mitigating Climate-Driven Scarcity

This Article examines hydroelectric resources’ ability to assist states throughout the West and across the country in meeting their statutory and policy goals of reduced or zero carbon emissions, while maintaining reliability. Extreme weather events, and associated costs, are not isolated to the Western Interconnection, but rather increasingly impact other regions and their end-use customers. In its 2021 U.S. Hydropower Market Report, the Department of Energy (DOE) noted that, in nearly every Balancing Authority Area assessed, hydropower was more extensively used for hourly ramping flexibility than any other resource. Additional services hydroelectric resources provide, including storage capacity and black start service to restore power without assistance from the grid, are critical in a context where extreme weather is the new norm