The coming years may be rooftop solar's time to shine

Science Friday
Rooftop solar on house

Rooftop solar power is booming. And as more and more consumers discover that prices for solar power are falling, they're slapping panels on their roofs and buying less energy from the power companies.

Are we really seeing a revolution in rooftop solar? “Yes,” says David Roberts, a staff writer at

“I think by any measure, the word revolution applies at this point,” Roberts says. “Just for perspective, the residential solar industry grew 76 percent in the last year in the US. ... It's exciting because I think we're right at the very, very beginning of it.”

In a recent speech, even President Barack Obama took note: “For decades,” he said, “we've been told that it doesn't make economic sense to switch to renewable energy. Today that's no longer true.”

Rooftop solar power still represents just a tiny percentage of overall US electricity production — less than 1 percent  — but the growth is exponential, Roberts says.

“It took well over a decade to double the amount of rooftop solar prior to this year,” he says. “Now it's expected to double again almost every year in the next few years. It's going to start to make a real dent within the next five or six years.”

As one might imagine, some utilities are not happy with this new reality. Others, however, are trying to embrace it.

Gil Quiniones, the president and CEO of the New York Power Authority, the largest state-owned electric utility in the United States, believes this could be an exciting time for utility companies, if they are willing to find ways to adapt.

"Utilities must find a way to integrate solar so that it also benefits the operation of their grids," Quinones says. “Utilities will have to modernize the grid that Thomas Edison and Nikola Tesla built. ... The grid will still exist, but it will help foster more distributed energy resources.”

Quinones also chairs the Electric Power Research Institute, which defines ‘distributed energy resources’ as “smaller power sources that can be aggregated to provide power necessary to meet regular demand.”

“The one-way flow grid will have to be bi-directional or even multi-directional, and utilities will have to adapt as distributed energy resources become more and more common,” Quinones says.

Roberts agrees. “It's less about physical infrastructure at this point than intelligence and coordination, since [so many] customers are now also producers,” he explains. “They produce energy, they store it, they can sell it when it's expensive, or store it when it's cheap. And so it becomes a matter of information technology. It's a matter of keeping track of all these tiny little producers — hundreds of thousands of them.”

Some utility companies are resisting this kind of change. Utilities in Arizona, for example, want to charge new rooftop solar customers a $21 monthly fee to connect to the grid, even if those cutomers generate all of their own energy.

Quinones believes this may not be the best way to adapt to a future that inevitably includes renewables. Roberts says the utilities may not have a choice.

“Utilities all over the country are fighting to put these new fees on solar homeowners, because they're panicking, but they're failing all over the place,” he says. The Nevada Public Utility Commission, he points out, just ruled against the new fixed fees, as did the state of Colorado.

“In about 20 states, utilities are trying to add these fees and they're losing everywhere,” Roberts says. “The only place they've won even a modest victory is in Arizona. So, I really think that changing the model, the regulatory model is the only way forward for utilities.”

Quinones says utility companies should transform themselves into ‘distribution service platforms.’ That is, instead of building new power plants and sub-stations, utilities should work with their customers and encourage them to install distributed energy resources.

“Distributed energy resources can actually help utilities in the planning and the operation of their grids,” he insists. “The big grid is still going to be there. But re-designing it so that the distributed energy resources will work in synchronicity with it is really the optimum way to serve the public.”

This article is based on an interview that aired on PRI's Science Friday with Ira Flatow

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