U.S. carbon emissions fell 3 percent from 2008 to 2009, the largest one-year drop on record since the government began keeping tab on such things in 1990, reports the Los Angeles Times.

Projected improvements in the economy should lead to a 1.5-percent increase in CO2 emissions in 2010, according to the latest Short Term Energy Outlook report from the Department of Energy.

With a projected 5.5 percent growth in manufacturing output during 2010, the Energy Information Administration says that electricity sales to the industrial sector will grow 1 percent.

The EIA estimates that residential consumers will boost their electricity consumption 3.5 percent this year with a return to a warmer summer.

Total consumption of electricity across all sectors is expected to grow 2 percent during 2010 and 1.5 percent in 2011.

Increased use of coal in the electric power sector and continued economic growth, combined with the expansion of transportation-related petroleum consumption, should lead to a 1.2-percent increase in CO2 emissions in 2011.

Still, even with increases in 2010 and 2011, projected CO2 emissions in 2011 are lower than annual emissions from 1999 through 2008.