The Effects of Resource Intermittency on Electricity System Emissions

Abstract:

Since society subsidizes the production of renewable electricity in order to decrease emissions from the electric power system, it is important to quantify the environmental benefits of renewables. We use the intermittency characteristics of renewable resources to assess the impact of renewable generation on the emissions of carbon dioxide and other air pollutants. Previous studies have investigated the impact of wind or solar generation on emissions; rather than focusing on a particular technology, we separate the intermittent resource into its components – specifically variability, predictability, and timing – and isolate the effect of each component. For the Texas electricity grid, we use the observed outputs of generating units to econometrically estimate the effect of each intermittency characteristic on CO₂, SO₂, and NO_x emissions. We then use the econometric results to evaluate and compare the expected emissions implications of adding different resources to the system. While the econometric estimates are derived from the wind currently online in Texas, the decomposition of the intermittency makes the results technology agnostic and allows for a comparison between prospective resources of different types. Preliminary results will be presented.