Nowadays, many countries have set ambitious targets for renewable energy penetration in the coming decades, as increasing variable renewable energy (VRE) is one of the main approaches for greenhouse gas (GHG) mitigation. However, in a recent study by Prof. Yang Yu’s group at Tsinghua University and his collaborators, it demonstrates that VRE crowds out nuclear power (VRECON) but cannot fully obtain the left market share, which is obtained by fossil energy, and this leads to a GHG increase risk associated with increasing VRE. They developed an integrated dispatch-and-investment model to estimate the VRECON GHG-boosting effect in the Pennsylvania-New Jersey-Maryland Interconnection and the Electric Reliability Council of Texas. In the above two markets, VRECON could increase the annual GHG emission by up to 136 MTCO2eq totally.
Furthermore, they find that the VRECON GHG-boosting effect can be mitigated by optimizing the mix of wind and solar power. To ensure future GHG emission reductions, the research suggested that policymakers should require the proper mix of wind and solar power associated with the Renewable Portfolio Standards. It is also necessary to manage the pace of nuclear power’s retirement to match the progress of VRE’s penetration.
The findings are published in iScience, which is a new open access journal from Cell Press that provides a platform for original research in the life, physical, earth, and health sciences. The first author of the paper is Professor Xiaoli Zhao from China University of Petroleum, and the corresponding author Assistant Professor Yang Yu.