New Berkeley Lab Brief on Value of Solar Studies with a Focus on Value Categories and Methodologies

Berkeley Lab has just released a brief titled A Review of Value of Solar Studies In Theory and In Practice. This brief is a result of technical assistance conducted under the U.S. Department of Energy-funded Resources and Assistance for State Energy Offices and Regulators program. In the brief, Berkeley Lab researchers summarize a collection of state- and utility-commissioned value of solar (VoS) studies and related literature, with a focus on who commissioned the study, which value and cost categories were discussed and/or quantified, and the methods used. 

Though most states in the United States required net metering as of 2024 (i.e., compensating solar output at the full electricity rate), many have taken recent action to address distributed generation compensation and valuation. One common action is for states to commission VoS studies that quantify the value and costs associated with distributed solar output to inform solar tariff and incentive design. 

The objective of this work is to compile information on prior VoS studies to inform state regulators and other stakeholders that may pursue related studies or integrate findings into ratemaking design. To do so, we summarized two meta-analyses that reviewed state- and utility-funded VoS studies conducted between 2005 and 2018 as well as four additional studies published from 2018 through 2023. While the brief goes into further detail on methodology and other specifics, Table 1 illustrates the value categories that were included in each of the four more recent studies and whether they were quantified, qualitatively included, or omitted. 

Table 1: Regions in which value of solar studies were conducted between 2018 and 2023 that are analyzed in this brief and whether each value and cost category were either quantified, discussed, or omitted

This brief is intended to contextualize and summarize the value and cost categories that have been included in past VoS studies and research as well as the methodology used to quantify these values. This can provide context to states that may want to do the same in order to understand or quantify the net benefits of solar or integrate findings into new or updated solar incentives or tariffs.

We thank the U.S. Department of Energy’s Office of Energy Efficiency and Renewable Energy for their support of this work.

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