Climate change is a challenging issue not just for electric utilities and Southern Company but for our nation and the world. Leadership on this issue requires developing and deploying technologies that reduce greenhouse gases while making sure that electricity remains reliable and affordable.
Carbon dioxide is a byproduct of combustion. Southern Company is researching—with the federal government and other partners—how to capture and store carbon dioxide emitted from power plants to keep it out of the atmosphere. (See also DOE Carbon Sequestration Atlas and Climate Challenge Emission Reductions.)
Carbon dioxide is neither the most widespread nor the most potent greenhouse gas. For example, water vapor is a greenhouse gas in higher atmospheric concentration while methane has a much stronger greenhouse effect.
Considerable progress has been made in controlling some anthropogenic (from human activity) greenhouse gases, like chlorofluorocarbons from refrigeration. Another lesser known gas, sulfur hexafluoride, has been a focus of Southern Company's attention. Sulfur hexafluoride has more than 20,000 times the global warming impact of carbon dioxide on a pound-for-pound basis.
Southern Company has about 500 transmission substations with 1,740 breakers that use sulfur hexafluoride for its essential insulating properties. By joining a voluntary EPA program to reduce sulfur hexafluoride emissions by better detecting and repairing leaks, Southern Company has made progress in reducing sulfur hexafluoride releases.
Measures taken have reduced emissions from the equivalent of about 660,000 metric tons of carbon dioxide in 1993 to an equivalent of about 100,000 metric tons in 2010. Emissions are expected to continue to decline and should reach an equivalent of 75,000 metric tons this year.
EarthCents programs reduce electricity consumption and consequently lower carbon dioxide emissions. More on EarthCents.
With other members of Edison Electric Institute, an association of shareholder-owned electric companies, we support climate change framework that calls for an 80 percent reduction of carbon emissions from current levels by 2050 and also recommends to Congress a unified industry position for allocating emissions allowances distributed to the utility sector under potential cap-and-trade legislation. Details on climate change position »
Over the past decade, Southern Company, with the Department of Energy and other partners, has been developing cleaner, less expensive, more reliable methods for power production from coal.
Rather than burning coal directly to make electricity, we're breaking coal down into chemical components. Impurities can be removed from the coal before it is fired, avoiding some emissions. Gases that result from this chemical breakdown can fuel integrated gasification combined cycle power plants, which are more efficient and therefore cleaner than current ones.
Now we've taken gasification one step further, a new process, called Transport Integrated Gasification, uses air rather than pure oxygen—and lower-grade sub-bituminous and lignite coals—to more affordably gasify the coal.
TRIG and other technologies developed at the National Carbon Capture Center will also make carbon dioxide capture and geological storage cheaper than capture and storage at existing coal-fueled plants. Look for TRIG to be used in the 582-megawatt gasification plant in Kemper County, Miss.