Editor's Note:
Over-the-counter prices for California carbon allowances eased in light trading during the week ended May 15, as the market awaited the results of the latest greenhouse gas allowance auction.
As of May 15, the May 2018 vintage 2018 California carbon contract was eyed in a bid-and-ask range of $14.65/tonne to $14.69/tonne, down 1 cent from prior assessments.
The benchmark December 2018 vintage 2018 California carbon contract was assessed in a bid-and-ask range of $14.97/tonne to $15.02/tonne as of May 15, easing 2 cents from the start of the month.


The market is taking a breather ahead of the May 23 release of the results of the latest quarterly allowance auction held by the Western Climate Initiative, or WCI, on May 15.
The sale offered more than 90.0 million current vintage allowances and more than 12.4 million advance auction allowances on the auction block. The current vintage offering consisted of more than 13.3 million 2016 allowances and more than 77.2 million vintage 2018 allowances.
In the WCI's prior auction in February, 100% of the more than 98.0 million current vintage allowances sold at US$14.61/tonne, or 8 cents above the price floor of US$14.53/tonne.
Under the WCI, the California and Quebec cap-and-trade programs were formally joined at the beginning of 2014, with their first joint auction held in November 2014. Ontario became the third member of the WCI on Jan. 1, allowing the three governments to hold combined auctions under the program.
Market prices and included industry data are current as of the time of publication and are subject to change. For more detailed market data, including power and natural gas index prices, as well as forwards and futures, visit our Commodities pages.
