Pros & Cons
In the U.S., the greatest source of human-caused greenhouse gas emissions is the power sector, at about 38%. The largest source of power is coal, which, even though it produces less than 40% of the power, produces over 70% of the power sector's greenhouse gas emissions. (20% of the greenhouse gas emissions are from natural gas-fired power plants.) Although wind turbines have become familiar in much of the U.S., wind power still (2013) only accounts for about 4% of the power sector.