"The House could vote today on a measure to cap U.S. greenhouse gas emissions, with Democratic leaders predicting a tight victory for a behemoth bill that has grown more complex with each compromise.
The heart of the bill, which now runs to 1,201 pages, is a plan to reduce emissions to 17 percent below 2005 levels by 2020. To do that, it would create a cap-and-trade system, in which polluters would be required to accrue buyable, sellable credits for all the greenhouse gases they produce.
But the bill also contains a system of caveats, safety valves and rule changes meant to satisfy unhappy Democrats. The result is legislation that could transform the U.S. energy industry -- and allow both Wall Street and the Corn Belt to build a side business in carbon."