Taking the Carbon Out of Coal

• Published: December 26th, 2009

Program Summary

A company called SCS thinks it can use coal to generate electricity while cutting down 90 percent on carbon emissions — and still make a profit. The company’s PurGen plant, which would be located on the site where an old Dow Chemical plant used to stand near the New Jersey Turnpike in Linden, NJ, would use a technology called carbon capture and storage, or CCS. Carbon dioxide coming from the coal would be captured and pumped in liquid form deep underground, where it would — presumably — stay. To continue using coal while achieving an 83 percent reduction in greenhouse gas emissions by 2050, as called for in proposed legislation being discussed in Congress, will require increasing amounts of CCS in the coming decades.

The PurGen plant would not burn coal, but rather turn it into hydrogen through a process that generates a stream of pure CO2 as a by-product. The hydrogen would be burned to make electricity with very little air pollution — but only when the demand for electricity is high, and the plant can get a good price. At times when demand is low, the hydrogen would be diverted and converted on-site into the chemical urea, used to make fertilizer.

The storage part of SCS's plan involves building a two-foot-diameter pipeline to carry liquefied CO2 from the plant, under the Arthur Kill — a waterway separating New Jersey from Staten Island — and 140 miles out to a point on the bottom of the Atlantic Ocean, where it would be injected and stored about 8,000 ft. beneath the sea floor in a suitable geological formation.

Supporters say the plan is a perfect solution to several problems at once — how to use the nation's cheap, plentiful coal supply without adding heat-trapping CO2 to the air, how to provide clean electricity to a part of the country that has to import power, and how to spark a green energy industry that could help the US maintain economic leadership in a time when China and other nations are determined to wrest it away.

But not everyone thinks the PurGen project is a good idea. For one thing, even if the plant makes electricity cleanly, the mining and transport of coal will still have environmental impacts. For another, some worry that sequestering CO2 underground hasn't been adequately tested yet. And other critics say the money for PurGen would be better spent on solar or wind energy or energy efficiency — challenging the very premise that finding a way to use coal without carbon emissions is needed.

Credits: The News Market, Shutterstock