Regulating Roof-Top Solar Generation: Defending Sustainable Projects from Utility Proposals

Residential owned solar panels mounted on roof-tops generated 1.4% of the U.S. electricity supply in 2022. Utilities compensate residential customers using a net metering system by which each kilowatt-hour generated by the customer reduces the customer’s bill by the amount the utility charges for one kilowatt. Despite the small impact of roof-top solar on the total market, in 2022, thirty-two states conducted ninety-four proceedings investigating whether to change the net metering system. In these proceedings, utilities advocated changing the rates to discourage residential investment in solar panels. Utilities argue that net metering provides a subsidy to solar customers because the rate the utility pays is greater than the avoided cost of energy. That excess payment allows solar customers to avoid paying for the distribution network. The cost of the distribution network is shifted to non-solar customers. This article will evaluate these claims. It will show that if the social cost of carbon were in the calculation, it would generate a Kapp cost shift from solar customers to non-solar customers. The size of the Kapp cost shift is greater than the cost of distribution networks, reversing any private cost shift that utilities have estimated.