Want to know which companies to thank for air pollution? Take a look at the University of Massachusetts Amherst Political Economy Research Institute's recent Greenhouse 100 Polluters Index, which calls out the companies with the highest greenhouse gas emissions (based on U.S. Environmental Protection Agency's Greenhouse Gas Reporting Program data from 2011).
As the Energy Capital of the World, Houston's oil and gas companies rank highly on the 2013 naughty list. NRG Energy Inc. (dual-headquartered in New Jersey and in Houston) comes in at No. 12, emitting nearly 44 million metric tons of carbon dioxide in 2011 — more than one-third of that from a coal-fired energy plant in Fort Bend County.
Calpine Corp ranked No. 15 with more than 38 metric tons of CO2 emissions, BP America, at at No. 19, released nearly 35 metric tons into the atmosphere and ConocoPhillips (pre-spin-off) ranked No. 20 on the list, released more than 31 metric tons.
Other Houston-area companies include Dynegy at No. 23; GenOn Energy (which was acquired by NRG Energy last December) at No. 24; Waste Management at No. 37, Shell Oil at No. 42; GDF Suez North America at No. 48; Ascend Performance Materials at No. 53; Southwestern Energy at No. 80; Marathon Oil at No. 82; PDVSA, the 100-percent owner of Houston-based Citgo Petroleum Company, at No. 89; and Motiva at No. 91.
Dallas-Fort Worth-area companies on the polluters list include Luminant General Company at No. 7 for leaking more than 61 million metric tons of CO2 and ExxonMobil at No. 14, with more than 39 million metric tons of CO2 reported in 2011.
San Antonio-based companies Valero and CPS Energy took Nos. 28 and 38 on the list, respectively, followed by Midland-based Dow Chemical at No. 44 and the Lower Colorado River Authority, out of Austin, at No. 58.