Integrating Renewable Energy into the Electricity Grid: Case Studies Showing how System Operators are Maintaining Reliability

This report provides in-depth case studies of the Electric Reliability Council of Texas and Xcel Energy Colorado to show how they integrate high shares of variable renewable energy. According to the authors, carefully examining the lessons learned in regions such as the ones they examined should help independent system operators (ISOs) and utilities ensure that significantly larger amounts of variable renewable energy can be integrated at small to modest costs while maintaining high levels of reliability.