Mass Audubon and Harvard Forest recently released their report “Growing Solar, Protecting Nature,” exploring strategies for limiting environmental impacts of ground-mount solar development in Massachusetts. EER contributed to the report by modeling the economic buildout of ground-mount solar required to meet net-zero emissions in Massachusetts by 2050 under different land use scenarios. EER’s analysis builds on the modeling we performed for the Massachusetts Clean Energy and Climate Plan for 2025/2030 and 2050 and leverages methodology we developed in the various Power of Place studies performed with The Nature Conservancy.
Researchers at Harvard Forest used GIS analysis to create three different ground-mount solar potential scenarios, each representing a different degree of forest and natural ecosystem protection. The least-protective Current Siting scenario identified over 1 million acres of land in Massachusetts suitable for solar development. The Protecting Nature—Mid-Impact scenario limited that potential to 94,000 acres, and the Protecting Nature—Low Impact scenario further limited potential to 38,000 acres.
Some key findings of EER’s energy system modeling under these three scenarios are:
It’s possible to achieve Massachusetts’ electric sector and economy-wide emissions targets under all three scenarios. Scenarios with more stringent land protections rely less heavily on ground-mount solar, making up the difference with more offshore wind and imported hydroelectricity.
More extensive land protections cause a shift from large ground-mount solar installations in forested areas to smaller projects in more developed areas—a result of opportunistically building on smaller, more distributed parcels in developed parts of the state. EER assumes that smaller ground-mount projects have higher levelized costs than larger projects, based on historical data from Massachusetts. The cost assumptions used in our analysis result in a 10% total cost premium for solar electricity in 2050 in the Mid-Impact scenario relative to the Current Siting scenario.
The Current Siting scenario results in significantly greater loss of carbon from forests than the Protecting Nature scenarios, per analysis by Harvard Forest. If we assume the long-term cost of carbon removal is $200/ton CO2e, the savings from reduced carbon removal required to meet net zero would fully offset the energy cost increases of targeted solar siting in the Mid-Impact scenario.
The full report is available here and includes Mass Audubon and Harvard Forest’s policy recommendations for minimizing land impacts of solar development in Massachusetts.