CO2 emissions limits for new US power plants proposed

On 20 September the United States Environmental Protection Agency (EPA) proposed the country’s first Clean Air Act standards to cut carbon pollution from new power plants to combat climate change and improve public health.

Power plants are responsible for roughly one-third of the country’s greenhouse gas emissions.

The proposed rules will require new fossil fuel fired power plants to capture and store a portion of the carbon dioxide (CO₂) they produce. Coal emits about twice as much CO₂ as natural gas when burned to make power.

According to the EPA’s proposal, new coal-fired units should meet a limit of 1,100 pounds of CO₂ per megawatt-hour (MWh). The limit for new large natural gas-fired turbines is set at 1,000 pounds of CO₂/MWh, while new small natural gas-fired turbines would need to meet a limit of 1,100 pounds.

A new coal plant without carbon capture is expected to emit some 1,600 pounds of CO₂/MWh while the average US coal plant emits 1,768 pounds. To meet the new limit, coal plants would have to capture and store about one third of the CO₂ they produce. Natural gas plants would not be required to capture their emissions.

David Goldston at the Natural Resources Defence Council said: “The most important thing about the new plant rule is that it’s crossing the Rubicon to say that we are going to put limits on carbon pollution. It’s important as a precursor for existing-plant rules.”

A more far-reaching set of final rules governing emissions from existing power plants is due by June 2014. With low-cost natural gas displacing coal in many power facilities, rules on existing plants will take on heightened importance.

The proposed rules will be open for public comment for 60 days before becoming final.

Sources: US EPA press release and bloomberg.com, 20 September 2013.