The outdated network has created an economic division of solar energy

If United States will one day make a breakthrough in the production of global warming carbon emissions, will have to reduce the use of solar energy, much of which can be generated from the roofs of homes and businesses. Solar provides only 3% of U.S. energy supplies today, but the White House and states like California are pushing to increase that to more than 40% in the coming decades.

To get there, homeowners and businesses will need more financial incentives to install photovoltaic panels, while large-scale solar farms will also need land and transmission lines to send energy from rural to urban areas. Last week, state regulators in California required builders to install solar panels and store batteries in new commercial and high-rise residential buildings. But a new study finds that some low-income neighborhoods and minorities may be abandoned, mainly because utilities have not improved the electricity grid equally everywhere.

Even if rooftop solar panels were free for everyone, the authors say, homeowners in those areas would not be able to use solar panel energy to operate appliances or charge electric vehicles without buying a special battery. This is because the mains in these areas cannot accept the extra electricity generated by the solar panels.

“There is not enough capacity for everyone to have solar energy, even if that solar energy is free,” said Anna Brockway, lead author of the study, published this week in the journal Energy of nature and a graduate student in the Energy and Resources group at UC Berkeley. “We find that these restrictions are stronger in communities identified with blacks and disadvantaged. These communities have an even smaller capacity of the household network to be able to receive the solar energy that people would like to receive. “

Brockway and her colleagues are studying Pacific Gas and Electric and Southern California Edison, two utilities in California, the state that produces the most solar energy in the country. PG&E’s service area extends from Shasta Peak south to Santa Barbara, while the SCE’s service area covers Los Angeles County, Orange County and San Bernardino County, as well as the Nevada border region. They chose these two communal areas because they have the largest use of solar energy in the state. Both serve high- and low-income areas, as determined by the census data, and together provide power to 30 million people.

The researchers compared the company’s own “hosting capacity” maps, which is how much energy the electricity grid can carry in each neighborhood, with data from a census of racial demographics and a block-level economy. They then calculated how much capacity the circuit would need to accommodate the sunroofs and distribute them in neighborhoods.

For decades, the power grid has been built to send electricity in one direction – from a power plant, through transmission lines, to home or business. But homeowners have started generating electricity and sending it in other ways. In richer areas and whiter communities, where solar panels have become common over the past few decades, utilities have upgraded equipment to make two-way electricity easier. “Early adopters disproportionately fit into certain demographic characteristics of being white and having a higher income than the average paid,” Brockway said.

But this is not the case in minority neighborhoods, where rooftop solar energy is less common. Take, for example, transformers that connect power lines to any home or business. The older ones are not designed to carry the extra energy generated by the roof panels in the opposite direction. Any additional current would be converted into heat, which could damage or destroy the transformers. “Every time you move electricity from one place to another, whether it’s solar or through the grid, to charge something, there will be an increased amount of energy flowing through the lines,” Brockway said. These lines, she continues, “are only able to handle a certain amount of current.”

This congestion could also make it harder to charge electric vehicles at home, says Mohit Chabra, a senior scientist at the Council for the Protection of Natural Resources, and it will make it harder for the United States to switch from electric electric cars to gas. “The fact that the grid is not ready to take on the level of electrification we want is not a good thing,” Chabra said. “We don’t want a situation where blacks and lower-income neighborhoods can’t charge their cars at home or near their homes.”