Rooftop solar is on the rise in Massachusetts

Boston- Massachusetts ranks fourth in the nation for growth in small-scale solar power generation in the past decade, according to a new report released today by Environment Massachusetts and Frontier Group. The report, Rooftop solar on the rise: Small solar projects are delivering 10 times as much power as a decade ago, celebrates the dramatic growth of rooftop solar, illustrates how far we have yet to go to take full advantage of our solar energy potential, and recommends policies to keep rooftop solar rising.

“In the transition away from fossil fuels, we must embrace renewable energy sources, including rooftop solar,” said state Representative Marjorie Decker, House Chair of the Joint Committee on Public Health. “I am thankful to Environment Massachusetts and my co-filer Rep. Sean Garballey for their partnership on the 100% Clean Act, which would require 100% of the electricity in Massachusetts by 2035 to be from clean energy sources like solar.” 

Rooftop solar reduces dependence on fossil fuels, eases strain on the grid during periods of high electricity demand, increases resilience to threats like extreme weather, and limits the amount of land needed for clean energy, all at a steadily falling cost. Small-scale solar energy, of which rooftop solar is the largest component – is growing rapidly in the United States, producing 10 times as much power in 2022 as a decade earlier. The trend holds true in Massachusetts, where small-scale solar produced 3,227 more GWh of energy than it did in 2012. 

“Today, in Massachusetts you can get your energy straight from your roof. Why pay for polluting energy from a power plant hundreds of miles away when we can just soak up the sun on our rooftops?” said Lydia Churchill with Environment Massachusetts. “If we want a clean energy future, we should be deploying rooftop solar everywhere we can.”

Rooftop solar has taken off over the past five years in Massachusetts. Residential solar grew 144% from 2017 through 2022. Over the same time period small-scale commercial solar grew 116% and industrial solar grew by 99%. In total, small-scale solar in Massachusetts generated 3,419 GWh of electricity in 2022 up from 1,516 GWh in 2017. 

“Environment Massachusetts’ analysis illuminates the fact that prioritizing rooftop solar brings a host of benefits to communities, to climate protection, and critically, to nature,” said Michelle Manion, VP of Policy & Advocacy at Mass Audubon, and co-author of the recent Growing Solar, Protecting Nature report.  “This report buttresses our work perfectly.  A shift away from large ground-mount solar in forests and on prime farmland towards rooftop and canopy projects will not only strengthen our push towards the state’s ambitious goals for climate and nature, but will also deliver grid benefits, lower costs, and create a more equitable and resilient energy system for the 21st century economy.”

Despite gains over the last decade, rooftop solar is still a largely untapped resource. The report finds that the United States has so far tapped only 1/28th of its rooftop solar potential. Rooftop solar has the technical potential to meet about 45 percent of national electricity sales in 2022, but in 2022 the U.S. only generated about 1.5 percent of all the electricity it used from rooftop solar. Massachusetts has tapped 10.8 percent of its rooftop solar generation potential, one of the highest in the country. 

The report identifies solar incentives, supportive rate design, interconnection policies and permitting processes as four crucial policies that can determine how successful a state is at tapping its rooftop solar potential. In Massachusetts, legislation is being considered to increase the pace to increase solar and transition the state to get to more clean, renewable energy.

“Given both our untapped potential for solar and the overwhelming need to reduce fossil fuels we cannot afford delay in deploying every tool in the toolbox to generate more clean, renewable energy sources like solar,” said Churchill.