Lessons from Renewables Planning in California and Suggestions to Korea

California has established aggressive Renewables Portfolio Standards (RPS) goals to increase the fraction of electricity generated from renewable energy resources and to decrease greenhouse gas emissions under AB 32. By 2010, 20% of California's electricity is required to come from renewables, and 33% has been proposed as a goal for 2020. Most of this new renewable generation will require the electric grid for delivering its electricity to customers. Renewable generators will be integrated into the electric grid at both the transmission and distribution levels, but most of them are expected to connect to the transmission system in locations remote from load centers and existing transmission infrastructure, thus requiring transmission extensions. Some of this renewable generation will exhibit properties quite different from traditional generation and loads, which pose special challenges for providing timely adequate grid delivery capacity, maintaining reliability, and avoiding economic inefficiencies. Finally, power flow constraints through transmission “gateways†into population centers must be relieved before the electricity from renewables can reach customers. In addition to constructing effective transmission interconnections between the renewable resource development areas and California's high-voltage electrical grid, it will be necessary to expand the transmission system capability between the backbone grid transmission gateways and from the transmission gateways to the local load centers. Meeting these challenges for the successful integration of renewables into the electric delivery system will require new or expanded capabilities for the grid. At higher RPS levels, the conventional “build†solutions alone will prove inadequate. New transmission technologies offer the prospect of providing a substantial portion of these new or expanded capabilities. In this report, we investigate how California is dealing with these challenges. We are covering current status, planning issues and operational issues of renewable energy. We hope this report is useful to whom studying renewable energy.