Most states show decreases in CO2 emissions
Written byChrista Marshall, ClimateWire
Carbon dioxide emissions from energy use declined in the majority of states between 2000 and 2010, according to an analysis released yesterday by the Department of Energy.
Led by big percentage decreases in CO2 emissions in Delaware, the District of Columbia, New York and Maine, states' overall energy-related CO2 emissions fell 4.2 percent during the decade. Thirty-two states witnessed an emissions decrease from 2000 to 2010.
The nation's two biggest emitters –- Texas and California –- saw CO2 emission declines of more than 3 percent, according to the analysis.
Perry Lindstrom, an industry economist at DOE, said reductions in energy intensity and switching from fuels like coal to renewables helped drive carbon dioxide output down over the 10-year period.
Forty-seven states reduced energy intensity, which measures energy consumed by unit of economic output, according to the department. Many states are detaching their economic growth from energy-intensive industries, Lindstrom said.
"Software designers are replacing steel plants," he said.
Wyoming leads in per-capita CO2 emissions
In Delaware, for example, per-capita emissions fell even more than the total statewide percentage, or by 36.4 percent over the decade. Energy intensity fell 34.6 percent in the state.
Similarly, energy intensity declined in some of the heaviest emitters, falling by more than 25 percent in Texas, Virginia, Wyoming, Maryland and Alaska, according to the data.
The numbers also outline the general emissions profile of the United States –- much of the nation's carbon dioxide emissions remain centered in coal-dependent states in the Midwest, in refinery centers like Texas and in population giants like California.
At 118.5 metric tons per capita, Wyoming has the highest per-capita emissions in the United States, followed by North Dakota, Alaska, West Virginia and Louisiana. The department noted those states are heavy fossil fuel producers with relatively small populations. Wyoming also has bitter winters, which drive up energy use.
New York has the lowest per-capita carbon dioxide emissions, largely because of heavy use of mass transit and "efficiencies of scale" in New York City. People sharing heating and cooling systems in large apartment buildings, for example, tend to use less energy than individuals in large homes.
2013 emissions could go up
State-level data from the department since 2010 are not yet available. However, emissions have continued their downward trend past 2010 at the national level. Energy-related carbon dioxide emissions in 2012 were the lowest in the United States since 1994, at 5.3 billion metric tons of CO2, the department said last month.
Lindstrom said, however, that 2013's data might show an emissions uptick, as higher natural gas prices allow coal to make some inroads in the fuel mix. Coal emits roughly twice the CO2 emissions of natural gas during the burning process.
The data released yesterday measure emissions at the location of fossil fuel burning. For example, they include emissions released from a power plant but not emissions from consumers who might use the imported electricity in a different state.
"An analysis that attributed 'responsibility' for emissions with consumption rather than production of electricity, which is beyond the scope of the present paper, would yield different results," the department said.
The issue has prompted some researchers to call for consumption-based methods for measuring states' carbon footprints. Last year, Stockholm Environment Institute analysts calculated that Oregon's emissions would be 47 percent higher under a consumption model of calculation.