Share story

OAKLAND, Calif. — The modern era of solar electricity got under way in 1954 as Bell Laboratory scientists unveiled a “solar battery” made from silicon that was used to power a toy Ferris wheel and a radio.

But solar, for much of the past 60 years, has languished in the shadows of energy technology as the silicon cells could never produce energy cheaply enough to compete with fossil fuels.

In recent years, solar has boomed as costs have declined and government policies have favored a renewable energy source that can help combat climate change.

Some of the strongest government support is in California, which is now the epicenter of the nation’s solar industry.

The state backs solar through financial incentives and a law that requires utilities derive 33 percent of their energy from renewable energy sources by 2020. The state also has created a system that caps carbon emissions and allows business to trade in a carbon market.

California’s solar energy generation hit a record earlier this year, accounting for 6 percent of energy from the California Independent System Operator, which manages the bulk of the state’s flow of electricity. Last year’s growth in solar capacity was greater than all earlier years combined.

This power flows strongest in the middle of the day, when demand is far from the peak in late afternoon to early evening.

That makes the grid increasingly difficult to keep in balance, and California now is making a whole new round of investments in battery and other storage systems that can capture some of that midday power for later use.

By 2020, the California Public Utilities Commission is calling for the development of 1.3 gigawatts of storage — enough to power more than 1 million homes.

Most of the solar power now produced in California comes from large centralized solar installations built in the desert.

The biggest is the $2.2 billion Ivanpah project built last year, which generates enough power to serve 140,000 homes. This system involves a vast network of 34,000 mirrors that concentrate the sun’s energy, with the heat generating steam to power turbines. The project has come under criticism for killing birds that fly through the site.

But about a third of the state’s total solar capacity comes from small-scale, rooftop photovoltaic installations that utilities must acquire, according to the California Solar Energy Industries Association.

On one block of modest stucco homes in the foothills of Oakland, three families now have solar panels on their rooftops.

Brian Wong, a 63-year old-retiree, said he used to pay about $90 a month for electricity. But after installing solar panels earlier this year, he found his the utility owed him $5.86 for surplus power he fed back onto the grid during the month of April.

“Why not invest in my future power? It makes sense,” Wong said. “It’s kind of like buying my own gas station.”

Wong says the $15,000 system will be paid off in seven years.

Some analysts predict solar will cause a major disruption of current utility business models as fewer traditional customers receive all their power from the grid.

That battle has raged most fiercely in California, Arizona and 13 other states where a private company has vastly expanded the numbers of rooftop installations by leasing out solar systems.

The California Public Utilities Commission is under orders from the legislature to come up with a new set of rules for utility purchase of rooftop solar energy.

Without changes, some analysts predict that the utilities are headed for financial troubles.

This spring, Barclay’s downgraded the bond ratings of the entire U.S. utility sector, forecasting that the combination of declining costs for both solar and storage would increasingly prompt power consumers to move away from grid power.

Other analysts say such concerns may be overblown.

Lawrence Berkeley National Laboratory researchers developed models for two different utilities that each got 10 percent of their power from small-scale solar installations. They predicted that utility rates over a 20-year period would increase by no more than 4 percent to cover the solar costs.

“That doesn’t sound too catastrophic to me,” said Galen Barbose, a co-author of the study.

Hal Bernton: 206-464-2581 or