In a First, Commercial Coal Plant Buries Its CO2
A coal plant in Saskatchewan will capture most of its carbon pollution—and use it to extract oil from the ground.
Capturing and burying carbon dioxide could play a crucial role in addressing climate change.
A coal plant that opened today in Saskatchewan captures and buries most of the carbon dioxide it emits—with a significant caveat: the carbon dioxide is being used to force more oil out of the ground.
The 110-megawatt Boundary Dam project, operated by provincial power utility SaskPower, is a refurbished coal-fired generator. It includes new post-combustion technology designed to absorb and capture 90 percent of the carbon dioxide in the plant’s exhaust, one approach to so-called carbon capture and storage, or CCS.
“It’s significant because it’s the first commercial-scale CCS installation at a power plant,” says Howard Herzog, an expert on carbon sequestration, and a senior research engineer with the MIT Energy Initiative.
The company argues in a statement that it is “transforming one of the world’s most abundant and affordable sources of energy to one of the cleanest.” However, the coal it’s burning, lignite, is the dirtiest around, and the 10 percent of CO2 that the plant can’t capture will still amount to 150 tons of carbon dioxide per gigawatt-hour. That’s better than the 420 tons emitted by a natural gas power plant but more than the life-cycle carbon dioxide emissions associated with a nuclear power plant, at 17 tons.
CCS may ultimately prove crucial to making headway on limiting emissions of greenhouse gases linked to climate change (see “The Cost of Limiting Climate Change Could Double without Carbon Capture Technology”). Yet the technology has mostly stalled. In North America, a coal plant with CCS in Mississippi has been long delayed. Another in Illinois only recently broke ground on a chimney (see “Construction Begins at a Carbon Capture Plant, but Will It Ever Be Completed?”).
With no tax or other price placed on carbon dioxide emissions, utilities have no impetus to get such projects going. Even the Saskatchewan plant wouldn’t have worked unless it used the carbon dioxide to force yet more hydrocarbons out of the ground, Herzog says.
The 565-megawatt plant in Kemper, Mississippi, will also burn dirty coal and use the captured emissions to force oil out of the ground. But it is five times larger than the Saskatchewan plant and will handle the coal with a different technology, gasification. The project has had huge cost overruns and is now projected to cost $5 billion, including hundreds of millions of dollars of federal subsidies.
This story has been updated to include emissions comparisons to natural gas power plants and nuclear power plants.
Hear more about carbon capture at EmTech MIT 2017.Register now