Pa. Reaches Another Solar Milestone

Pennsylvania’s solar output has doubled in just 17 months, a rapid growth in a state that has historically lagged behind its neighbors in terms of renewable energy adoption. The state recently reached 2 gigawatts of installed solar generation The growth has been made possible by both residential rooftop systems and large utility-scale systems, adding several hundred gigawatt-hours of production to the grid.

But the increase has to be read against the structure of the PJM system that oversees the regional electric grid for the Mid-Atlantic states, including Pennsylvania. PJM remains dominated by fossil fuel electricity sources. In 2024, natural gas accounted for roughly 44.5% of its generation and coal provided 14.5%. Nuclear added another 32%. Solar and wind together remain marginal in the mix, with wind at 3.7% and solar at just 2.1%, and the lengthy interconnection process makes near-term expansion uncertain. Historically, less than a fifth of renewables in PJM’s queue have reached commercial operation, even as applications multiply.

The structure of PJM’s capacity market compounds the problem. In the most recent auction, covering the 2026/2027 delivery year, only about 1% of the electric capacity came from solar and 3% from wind. By contrast, natural gas represented 45%, coal 22%, and nuclear 21%. Prices jumped 22% compared to the prior auction, indicating that conditions are tightening, but the clearing mix shows little large-scale shift toward renewables, despite the rapid expansion in Pennsylvania generation.

While Pennsylvania has seen a dramatic increase in the amount of solar capacity generation in recent years, it is unclear whether this trend will continue. The state still places a large emphasis on fossil fuels, as the industry is one of the leading employers in the region. Recent policy shifts away from renewable energy subsidies at the federal level and the surge in electric demand due to continued electrification of homes and automobiles, as well as a rapid increase in data center projects, has made reliable, baseload energy from fossil fuels more attractive. However, the governor has expressed support for an all-of-the-above energy strategy and for updated alternative energy standards that would mandate more of the state’s energy to come from renewables.