Acid rain, mercury pollution, and huge amounts of the heat-trapping gas carbon-dioxide are the down sides of burning coal in electric power plants. And yet, some energy experts are saying America should be using more coal. They say new coal technology can produce electricity with few of the pollution problems of traditional coal power plants. Bob Kelleher reports:
Acid rain, mercury pollution, and huge amounts of the greenhouse gas carbon dioxide are the down sides of burning coal in electric power plants. And yet, some energy experts are saying America should be using more coal. They say new coal technology can produce electricity with few of the pollution problems of traditional coal power plants. Bob Kelleher reports:
Coal has a well deserved bad reputation. Typical coal burning power plants release mercury, sulfur, nitrogen oxides, and lots of carbon dioxide. Those releases mean toxins in the air, soot, acid rain, and many believe global warming. But Tom Micheletti says there’s a way to use coal with very little pollution.
Using heat, steam, pressure, and oxygen, coal can be broken down to a relatively clean gas, and a handful of other chemical products. The gas is burned, to turn generators and produce electricity. The technology is called Integrated Gasification Combined Cycle. Micheletti says, the technology isn’t new, but applying it this way is.
“All we’re doing is marrying the gasification technology, with a technology that’s been well established, the combined cycle gas technology – power plant technology. And all we’re doing is simply putting those two technologies together.”
Micheletti is Co-President of Excelsior Energy, a company formed to build the nation’s first large scale coal gasification electric power plant in northeast Minnesota. At 600 megawatts, it would dwarf demonstration plants now online in Indiana and Florida.
Some experts say coal gasification is not only promising, it’s more practical than nuclear power, natural gas, solar or wind. Daniel Schrag is a climatologist and head of the Harvard University Center for the Environment.
“We have a lot of coal in the US. We’re very fortunate that way. The problem is that coal produces more carbon dioxide per unit energy than any other fossil fuel. And so, when we burn coal and make electricity, it’s really bad for the climate system.”
Schrag says there’s more carbon dioxide around us now than humans have ever experienced. Carbon dioxide is a greenhouse gas. Most scientists believe it blankets the earth, forcing temperatures higher.
Schrag says, when used to generate electricity, coal gasification has big advantages over conventional power plants, because it can capture CO2.
“You get more energy for the amount of coal you put in, and that’s good for carbon emissions. The other thing is that it seems to be cheaper in an IGCC plant, or a gasification plant, to capture the carbon dioxide after one extracts the energy from the coal, and then makes it much easier to capture it and inject it into a geological reservoir.”
The key, Schrag says, is a process called sequestration. You capture, and then sequester it, or lock that carbon dioxide away, where it won’t escape into the atmosphere. It’s already being done.
This is the Dakota Gasification Company, just outside Beulah, North Dakota. Here they turn coal into a burnable gas and almost a dozen other products. They also produce plenty of carbon dioxide, but the CO2 is not vented into the air; it’s trapped and compressed. That’s the noise.
The CO2 is piped more than 200 miles into Canada where it’s pumped into oil wells, forcing the last oil out and leaving the CO2 underground. Near oceans it can be pumped under deep ocean sediments, where it stays put.
And that’s all very good, but others say even good power plants might be a bad idea.
Ross Hammond is with the Minnesota based organization Fresh Energy. Hammond says gasification’s proponents are overlooking conservation and the opportunities for clean energy.
“When we’ve exhausted all the clean options including biomass and photovoltaics, and wind and the other options, then we need to look at coal.”
But Harvard’s Daniel Schrag says it’s not as simple as pushing money toward pollution free energy.
“And the answer is complicated. The answer is perhaps not. It may be that coal is so cheap that even the extra cost of capturing the carbon and storing it underground may still make it cheaper than the alternatives, than wind and solar.”
Schrag says we’ll need it all – nuclear, hydro, wind and biomass. But to satisfy the nation’s hunger for energy, he says we’ll need coal – best used in coal gasification.
For the Environment Report I’m Bob Kelleher.