California’s second cap-and-trade auction today

California’s second cap-and-trade auction is being held today, with more than 23 million greenhouse gas emission credits on the block.

The credits, known as allowances, allow industries and other emitters of greenhouse gases to continue in operation as they gradually reduce emissions as required by state law. Several hundred entities are expected to participate in today’s three-hour event, which concludes at 1 p.m.

The allowances, each of which is worth a metric ton of carbon emissions, are sold in blocks of 1,000 units each. Going into the auction, the minimum per-allowance price, known as the reserve, was $10.71.

At the state’s first cap-and-trade auction last November, the reserve was about $10.05. That event brought in some $285 million, largely for utilities’ issues, including ratepayers’ relief, and some proceeds went for environmental protections.

The Air Resources Board, which supervises the auctions, said 12.92 million allowances were available in the latest auction for 2013, and some 9.56 million advance credits were up for sale for 2016.

The auctions are a critical piece of California’s law to curb carbon emissions, AB 32. The law requires greenhouse gases to be reduced to 1990 levels within the next seven years.

The proceeds of the latest auction will be distributed by March 11.