Crediting Wind and Solar Renewables in Electricity Capacity Markets: The Effects of Alternative Definitions upon Market Efficiency
研究了容量市场中可再生能源容量信用的不同定义如何影响市场效率，发现不准确的信用核算与税收补贴叠加时效率损失可达6.3%，并提出了基于边际贡献的优化方案。
ABSTRACT As the penetration of variable renewable energy in electricity markets grows, there is increasing need for capacity markets to account for the contribution of renewables to system adequacy. An important issue is the inconsistent industry definition of capacity credits for resources whose availability may be limited, such as renewable generation. Inaccurate credits can subsidize or penalize different resources, and consequently distort investment between renewables and non-renew- ables, and also among different types and locations of renewables. Using Electric Reliability Council of Texas (ERCOT) data, we use a market equilibrium model to quantify the resulting loss of efficiency due to capacity credits alone and in combination with renewable tax subsidies and portfolio standards. Layering inaccurate capacity credits with existing US federal tax subsidies decreases efficiency as much as 6.3% compared to optimal capacity crediting under those subsidies. Compensating producers based on their marginal contributions to system adequacy, considering how renewable penetration affects the timing of net load peaks, can yield an efficient capacity market design.