As the world deploys more variable and intermittent renewable energy capacity, power system operators increasingly need to make decisions that curtail the power that those sources generate to ensure the reliability of the electric power system. Curtailment refers to the reduction in power production from a generator to accommodate grid or environmental constraints.
In order to enhance the economic performance of renewable generators (and avoid wasting valuable low-carbon electricity), policymakers might choose to implement curtailment caps: policies that penalize curtailment beyond a certain percentage of produced power. Although well intentioned and creative, the impact of these policies has been understudied.
In research published recently in iScience, Ahmed Abdulla worked with colleagues to better understand how curtailment caps might impact the cost, reliability, and emissions of the Chinese power system. They find that capping curtailment increases costs and emissions while also threatening the reliability of the power system by increasing the instances of over and under-generation. Moreover, it depresses further deployment of renewable energy capacity and encourages flexible fossil resources that can address reliability concerns. The research team concludes that policy makers must think carefully about the unintended and potentially deleterious effects of such curtailment cap policies.