If anybody doubts that federal energy regulators are aware of the rapidly changing electricity landscape, they should talk to Jon Wellinghoff, chairman of the Federal Energy Regulatory Commission (FERC).

“Solar is growing so fast it is going to overtake everything,” Wellinghoff told GTM last week in a sideline conversation at the National Clean Energy Summit in Las Vegas.

If a single drop of water on the pitcher’s mound at Dodger Stadium is doubled every minute, Wellinghoff said, a person chained to the highest seat would be in danger of drowning in an hour.

“That’s what is happening in solar. It could double every two years," he said.

Indeed, as GTM Research's MJ Shiao recently pointed out, in the next 2 1/2 years the U.S. will double its entire cumulative capacity of distributed solar -- repeating in the span of a few short years what it originally took four decades to deploy.

Chart: GTM Research/SEIA U.S. Solar Market Insight

Geothermal, wind, and other resources will supplement solar, Wellinghoff said. “But at its present growth rate, solar will overtake wind in about ten years. It is going to be the dominant player. Everybody’s roof is out there.”

And those other resources have not seen declining prices like solar has. “Solar PV is $0.70 or $0.80 per watt to manufacture. Residential rooftop is $4 to $5 per watt. But they are going to drive that down to $2 and then to $1 per watt.”

Advanced storage technologies also promise lower costs, he said. “Once it is more cost-effective to build solar with storage than to build a combustion turbine or wind for power at night, that is 'game over.' At that point, it will be all about consumer-driven markets.”

Wellinghoff was a consumer advocate early in his career and has not changed sides. “Even though the FERC oversees wholesale markets, utilities, and other jurisdictional entities at the wholesale level, the consumer needs to be our major concern," he said.

If FERC does not ensure the grid is ready to integrate the growing marketplace demand for distributed solar and other distributed resources, Wellinghoff said, “We are going to have problems with grid reliability and overall grid costs.”

Transmission infrastructure will be able to keep up with solar growth. The big changes will be at the distribution level where FERC has less influence, he explained. But the commission has been examining the costs and benefits of distributed generation (DG) in wholesale markets.

“Rate structures need to be formulated in ways that fully recognize the costs and benefits of distributed resources,” Wellinghoff said. “In many utility retail rates, a disproportionate amount of the fixed costs are recovered through a variable rate. That is problematic when a lot of people go to distributed generation.”

The net metering controversy this has caused at utilities like Xcel and Arizona Public Service, he said, can only be resolved by “the fully allocated, fully analyzed cost and benefit study of distributed resources.”

There is value in distributed solar, Wellinghoff said, “that can be captured and realized by the distribution utility that is not being paid to PV system owners because they have not been analyzed, quantified, and monetized.”

The Crossborder Energy study in California concluded the benefits of DG are near retail rates, he noted. “If utilities say that study is wrong, let’s get their studies and the studies from the solar side, and let’s have a hearing, let’s have full discovery, and let’s have a fully litigated process. That’s what regulatory commissions at the federal and state levels are for, to put all that data on the table and see what the accurate answers are.”

FERC isn’t involved in that process because it is a retail rate issue, Wellinghoff explained. “But DG and distributed solar can be wholesale grid resources if a wholesale grid operator can access those resources and have some control over them. What FERC has to do is ensure these distributed systems get recognized and compensated and integrated into the wholesale grid.”

If he was put in charge of updating the retail utility business model and pushing it to incorporate DG, Wellinghoff said, he would introduce more competition.

“I would unbundle utility services,” he said. “I would do a full analysis of anything not now competitive, like the distribution system, and then try to ensure I could recover costs in a way that adequately reflected all costs and benefits for all users.”

The sales of retail energy, capacity, and ancillary services should all be competitive and coupled with the wholesale grid, he said.

“Consumers should have access to and be able to respond to five-minute wholesale prices. They should have the opportunity -- not the requirement, but the opportunity -- to respond to those prices and modify their loads and usages to lower their energy costs. The result would be an optimized use of the grid.”

Watch Wellinghoff answer a caller's question about distributed solar: