Review on climate and water resource implications of reducing renewable power curtailment in China: A nexus perspective

As the transition towards a clean energy system is indispensable for combatting climate change and realizing low carbon development, China has enforced a series of policy incentives and investments to expedite renewable energy production. Such an acceleration is, however, contradictory to serious renewable power curtailment occurring recently. Taking on a water-energy-carbon nexus perspective, the impact of such curtailment can be of multifold, far from a lens viewing the mere loss in productivity of renewable energy sources. This study extensively reviews relevant literature to examine the causes and consequences of renewable power curtailment in China, and the inter-connections between water, energy, and carbon emission in power generation. Then two types of experiments are designed, namely the complete-depletion experiment and the partial-depletion experiment, to assess the potential implications on carbon emission and water resource if a range of incremental curtailment reductions applies. The experiments manifest that reductions on renewable energy curtailment would spawn notable reductions in carbon emission and savings on water resource, given the fact that renewable energy, particularly wind and solar power, would require far less water use and emit no carbon emission in their electricity generation than fossil-fired thermal power. We demonstrate that reduction of wind power curtailment would produce the most significant environmental benefits, followed by reductions of solar power and hydropower curtailments. The analytical results highlight the urgency and significance of addressing the renewable energy curtailment challenge experienced in China, which in turn requires synthetic introspection and consciousness on China’s power system transformation policy and its practices. Expected advancement in technical solution and market reform in China calls for enhancing the flexibility of the whole energy generation-trade system with increased, stabilized quotas for renewable energy production.