Full Title: The Role of Hydropower Flexibility in Integrating Renewables in a LowCarbon Grid
Author(s): Greg Stark and Greg Brinkman
Publisher(s): National Renewable Energy Laboratory
Publication Date: September 23, 2023
Full Text: Download Resource
Description (excerpt):
Power system flexibility makes the deployment of variable renewable energy (VRE) easier and more cost-effective to integrate into an existing grid. Dispatchable hydropower’s flexibility can help with this process, but its particular benefits to the power system have been difficult to quantify. In this work, we investigate the issue by taking a high-level yet quantitative look at the value that hydropower flexibility offers in terms of services that are helpful in integrating variable renewable energy, with a focus on firm capacity and operating reserves. We found that the flexibility associated with dispatchable hydropower’s ability to respond to load offers approximately 24 gigawatts (GW) of firm capacity. This 24 GW is in addition to both the 18 GW that would still be available if dispatchable hydropower were operated as run-of-river (i.e., dispatchable hydropower’s flexibility accounts for 58% of the firm capacity it provides) and the 13 GW of firm capacity provided by run-of-river. Also of note is that the contributions of firm capacity provided by hydropower’s flexibility vary markedly by region, ranging from 31% in the New York Independent System Operator (NYISO) region to 85% in the PJM region. Finally, in addition to the firm capacity benefits, we found that hydropower’s flexibility offers low-carbon operating reserves that can support approximately 140 GW of VRE, which is almost 10% of the VRE estimated to be necessary to achieve the administration’s goal of a net-zero carbon grid by 2035.