UPDATE 1-California wants EPA to slow down climate rules

* Rules would bog down development of renewables-CEC

* Latest hurdle to quick EPA crackdown on greenhouse gases (Adds EPA comment in last paragraph)

WASHINGTON, Jan 11 (Reuters) - California has urged U.S. environmental regulators to slow down implementation of rules on greenhouse gas emissions, saying they could hurt the state’s plans to transform its energy system to run more on renewable energy like solar power.

The Environmental Protection Agency proposed last year to require power plants and factories emitting more than 25,000 tons of greenhouse gases a year to obtain operating permits. The EPA has said the rules could take effect as soon as this spring.

The California Energy Commission supports the rules, but urged EPA to phase them in slowly.

“We believe such an approach would avoid the disruptive effect of the current EPA proposal,” the CEC said in a letter sent in late December to the EPA. It said the proposed rules, as written, would “likely retard, rather than facilitate, reductions in (greenhouse gas emissions) from the electricity sector.”

As part of California’s plan to build more wind and solar power farms, which generate power sporadically, it would construct a fleet of highly efficient natural gas-fired power plants to back those systems.

The new rules could slow down the permitting process of those new natural gas plants, and, in turn, the build out of renewable energy, the letter said. It would also increase reliance on older, less efficient natural gas plants that are not designed to work with renewable energy.

California passed its own climate law in 2006, in the absence of federal climate regulation, that would require the country’s most populous state to cap greenhouse gas emissions at the 1990 level by 2020.

The Obama administration prefers to control U.S. greenhouse gas emissions through legislation rather than by EPA regulation. But, to prod business to support the climate bill that is delayed in Congress, the administration also has pressed the EPA to take early steps on regulating greenhouse gases.

California’s request represents the latest hurdle for quick EPA implementation of rules on emissions of the gases scientists blame for warming the planet.

Oil and gas groups oppose the rules. A beef group last month challenged in court the EPA’s finding that the emissions endanger human health. Other states such as Kansas, Pennsylvania and Florida have also urged EPA to slow down.

An EPA spokeswoman said the agency was still reviewing comments and that no decisions have been made about the final rule. (Reporting by Timothy Gardner; Editing by Marguerita Choy and Walter Bagley)