Solar Capital

Across the country, shopping malls, schools, factories and other large non-residential buildings are basking in the sun, a powerful and too often wasted source of electricity that could serve the neighborhoods around them.

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Installing solar panels on these vast rooftops could provide one-fifth of the energy needed by disadvantaged communities, bringing renewable energy to people who can least afford it, according to a Stanford University study. While such power-sharing arrangements exist, the study found that marginalized neighborhoods generate almost 40% less electricity than affluent neighborhoods. “We were surprised to see that there was still such a big difference,” said Moritz Wussow, a data and climate scientist and lead author of the study.

This imbalance, often called the solar equity gap, is even more prevalent in home installation numbers. Placing solar panels on top of large commercial buildings can provide renewable energy to tenants while also helping homeowners who cannot afford the high upfront costs of this technology. Previous research by Wussow’s colleagues found that wealthy households are more likely to take advantage of tax credits and rebates aimed at making solar energy more affordable.

For the federal Solar for All program funded by the Inflation Reduction Act, which is expected to provide $7 billion to states to provide more equitable access to clean energy, the study shows that using commercial rooftops can be an effective way to reach two-thirds of people in disadvantaged communities in the country and start to close this gap.

“The transition to renewable energy is one of the main pillars that the government wants to spend money on,” Wussow said. “Our research aims to contribute to reducing the equity gap and give an idea of ​​how this can be achieved.”

Using DeepSolar, Stanford’s AI-powered satellite imagery database, the study counted the number of solar panels on large roofs of at least 1,000 square feet across the United States. To help research better inform policy, it examined the prevalence of these panel boards in census tracts identified as disadvantaged by the federal Justice40 environmental justice initiative.

These areas, which must generate low incomes and cause additional environmental burdens such as pollution, make up approximately one third of the census areas. The researchers then calculated the cost of generating solar power on nonresidential buildings in these areas and found that even in states like Alaska, where the sun doesn’t shine for almost two months of the year, the cost per kilowatt will still be lower than the local utility rate. If companies produce their own energy and share it, the results show that residents of surrounding neighborhoods can save and meet at least 20% of their annual energy needs.

Despite prevailing capital gaps, community solar projects have been around for over a decade. “I like to think of it as a model, an accounting mechanism where people, whether they own or rent, can participate in the transition to solar energy,” said Matthew Popkin, U.S. programs manager at RMI, a nonprofit -profit dealing with research on sustainable development. Most on-site solar systems are subscription-based, in which homes connected to on-site solar panels pay for a portion of the energy. Such programs help neighborhoods in cities from Denver to Washington, D.C. save money and ditch fossil fuels.

“There is no one-size-fits-all approach, there is no model that works for every community or city as a whole,” Popkin said. “More creativity will likely help move this issue forward.”

Boston, a city that lacks open space but has plenty of rooftops, could soon see the rise of community solar installations in commercial buildings. The Boston Community Solar Cooperative, which launched in March of this year, will begin its mission to provide clean energy to disadvantaged households with an 81-kilowatt solar array placed on a grocery store in Dorchester, one of the city’s lowest-income neighborhoods. Gregory King, president of the cooperative, said the project is only possible because of solar tax credits provided by the Inflation Control Act.

“The idea behind this model is really to empower the community,” he says. “We need to create more and more, especially rooftop solar panels, in an urban environment like Boston.”

Recent changes in the way utilities buy solar energy from homes, a process called net metering, have resulted in a decline in residential installations. But with Solar for All funds expected to be distributed to states as early as July, experts like Popkin say these new resources could shape the next wave of community solar. “The biggest unknown we have right now is what some of these exact funding structures will look like,” he said, but inclusive planning will be key. As communities across the United States race to reap the benefits of clean energy, encouraging businesses to go solar and share the rewards can ensure a brighter future for all.

This article was originally published in Milling On

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