A tax by any other name.  The Heritage Foundation has a good summary of Obama's energy budget here:

"While the budget blueprint euphemistically refers to this money as "climate revenue," in reality it is an energy tax that would force consumers to pay higher energy prices. In the blueprint, $646 billion of revenue would be generated through a cap-and-trade plan from 2012 through 2019, but many have suggested these auction permits would likely be much higher. The Heritage Foundation's Center for Data Analysis's estimate of climate revenue for 2012–2019, using less strict Lieberman-Warner caps, is between $1.6 trillion and $1.9 trillion, which results in even higher taxes on the consumer."