High-Elevation Hydropower and Climate Warming in California

Abstract

In California Climate warming is expected to shift the runoff peak from s pring to winter from a reduction in snowpack. For high -elevation hydropower plants, this shift can have important effects on power generation and its economic value. With over 150 hydropower plants in California , estimation of climate warming effects by co nventional simulation or optimization would be tedious and expensive. Two approaches are suggested to estimat e climate warming effects on high -elevation hydropower in California. The first (No -Storage) approach neglects available storage capacity and produ ces an upper bound estimate of lost generation and hydropower revenues from climate warming. The second (No -Spill) approach estimates the available energy storage capacity assuming that existing capacity is enough to avoid spill from high -elevation reservo irs with historical mean flows , providing a lower bound estimate of generation and economic losses . The generation changes in dry and wet climate warming scenarios at different elevation ranges are simulated in aggregate for several climate change scenario s and compared to the historic generation .