We cannot just swap 24/7 fossil fuel power plants for intermittent renewables. To prevent electricity shortfalls the capacity of a solar or wind plant must exceed that of the fossil fuel plant it replaces. But by how much? That’s the question that the Effective Load Carrying Capability (ELCC) metric is designed to answer. It’s not a new concept, but is now becoming very important. Mark Specht at the Union of Concerned Scientists explains the … [Read more...]