Creative Commons/Börkur Sigurbjörnsson

Electric power lines in San Francisco

Low-income and energy-efficient Pacific Gas and Electric Company customers will see their electricity bills start to rise this summer, while households that use lots of electricity will start to receive less-expensive bills.

The sweeping billing changes, sought by PG&E, were approved Thursday with a 4-0 vote by the California Public Utilities Commission. But the commission rejected a bid by the company to introduce a controversial new monthly fee of at least $2.40 per customer.

San Francisco customers who spend less than about $120 a month on electricity during the summer will generally see their bills rise under the new rates system, while customers spending more than that amount will see bills fall, The Utility Reform Network, a consumer advocacy group, calculated.

Low-income San Francisco residents earning less than twice the federal poverty level, such as a four-person household living on $40,000 a year, would see a $44.71 monthly bill rise to $51.05 this summer and rise again to $54.16 in 2013, TURN calculated.

In Bakersfield, where electricity use is higher than in the city because of differences in climate and housing designs, customers spending less than $230 in summer will generally see their bills rise, TURN determined, while customers spending more than that will start paying less.

The changes represent the most radical overhaul of PG&E's residential rates in a decade and are designed to alleviate pressure on heavy electricity users, such as residents of big houses that are constantly heated or cooled. About one-quarter of PG&E's residential customers — those who use the most electricity — have borne virtually all of the company's rate hikes since 2001 under a system designed to promote energy conservation and protect low-income Californians from rising energy prices.

PG&E has described the high per-kilowatt prices charged to its biggest customers as unfair and in dire need of reform.

TURN and the Greenling Institute, which represents communities of color, cheered the rejection of PG&E’s flat monthly bill but characterized other aspects of Thursday’s ruling as a mixed bag.

“This doesn’t really solve the fundamental problem, which is that PG&E’s rates are simply too high — they have some of the highest average rates in the nation,” TURN staff attorney Matthew Freedman said after Thursday's hearing. “The exercise today was a zero-sum game. It doesn’t make the pain go away, it just spreads it around for more people.”

Thursday’s ruling will change the way PG&E sets residential customers' electricity prices. The formula varies depending on where residents live and how much power they consume. The changes will start to take effect next month and will continue to be rolled out until 2013.