Solar to Grid – Market Value and Bulk Power Impacts of US Solar Through 2019

August 21, 2021

Solar to Grid – Market Value and Bulk Power Impacts of US Solar Through 2019

With continued deployment of solar across the United States, assessing the interactions of solar with the power system is an increasingly important complement to studies tracking the cost and performance of solar plants. This presentation focuses on the historical contribution to reliability, trends in market value, and impacts on the bulk power system of solar deployed in the U.S. through the end of 2019 with preliminary data for 2020.

Specifically we will cover growth in solar generation and associated market penetration as well as solar’s contributions to resource adequacy based on various calculation methods. We will present solar’s energy and capacity value, market value decline with growing solar penetration, and overall competitiveness relative to solar’s PPA prices and LCOE estimates. Finally we will highlight the implications of solar growth for wholesale price patterns, ancillary service requirements, changes to net-load ramps, and overall demand for increased flexibility.

The scope of this analysis includes the seven organized U.S. wholesale power markets and is based on historical hourly solar generation profiles for each individual plant larger than 1 MW or county-level aggregate profiles for smaller solar. In addition, we present a limited set of results for ten utilities that are outside of the independent system operator (ISO)/regional transmission organization (RTO) markets.

More information (a technical report, briefings, underlying data, and interactive visualizations) can be found at