After an all-day session Thursday, the California Air Resources Board voted 9 to 1 to approve the plan, which takes effect 2012, the San Francisco Chronicle reported Friday.
Board Chairwoman Mary Nichols called the proposal "historic," saying the cap-and-trade program "really builds on a history, a legacy of leadership in our state."
The new proposal essentially states the number of metric tons of carbon dioxide emissions will be capped in 2012 at what is forecast to be emitted that year. During the next three years, the limit is expected to shrink by 2 percent per year. From 2015 to 2020, the cap will drop by 3 percent per year, the Chronicle reported.
California's biggest emitters, including utilities and large industrial plants, can expect to feel the impact first, with fuel distributors feeling it in 2015. The proposal will apply to 360 businesses at 600 locations across the state.
Industrial sectors are to receive free credits equal to about 90 percent of the overall average emissions for their sector. Businesses will pay for excessive emissions by buying allowances -- or credits -- if they find they are unable to reduce their carbon dioxide levels, the Chronicle said. The proposal provides for up to 8 percent of emissions to be covered through "offsets" -- environmental actions such as planting trees to offset pollution.
Critics, including environmental organizations, call for changes in the offset program involving forests, arguing current written rules could promote clear-cutting of forests on land that might be eligible for tree-planting credits, leaving huge areas of forests with trees of the same age, which they say would do more harm than good.