The effort to reduce our nation’s greenhouse gas emissions has inevitably lost the attention of the public, and of distracted Washington officials, during the Iraqi crisis. But the problem remains, and current developments are making it even more urgent to find a solution.

Our nation’s coal plants alone are responsible for about 10 percent of the world’s greenhouse gas emissions. Anyone who is aware of the record amount of coal being burned to produce more than 50 percent of the electricity used in the United States – well over 1 billion tons a year – should not be surprised by the harm it’s doing to the environment. The fundamental coal problem is that no proven technology exists to remove or capture carbon dioxide at coal plants, or to sequester the greenhouse gases underground.

But what may astonish even the most jaded critics of the fossil-fuel industry is that more than 150 new coal plants – almost all of them old-fashioned, pulverized coal-burning units – are planned or under construction in the United States, despite growing public concern about climate change. When they go into operation they will increase the amount of power generated by coal in the United States by some 50 percent – and increase the greenhouse gases that coal plants generate by almost as much.

Many of the new coal plants will provide new capacity to meet our increasing demand for electricity. But some of them will displace existing plants that are fueled by natural gas – plants that emit only about half as much carbon as coal. So our main electric power generation trend is actually leading to an increase in greenhouse gases, not a reduction.

As for clean-coal technology, it is still a hope for the future. The most promising technology, integrated gasification combined cycle, or IGCC, reduces sulfur dioxide, mercury and particulate emissions but not carbon dioxide, and it performs well only with certain types of coal. Neither the technology nor its economics has been proven. Little wonder there are only two IGCC plants in operation in the United States.

The great challenge we face in the electric power sector is to rein in the amount of new generation that is fueled by traditional coal technologies, releasing their great quantities of greenhouse gases, and replace as much of it as possible with emissions-free power sources. And the greatest opportunity for that substitution lies in nuclear electric power.

Nuclear power plants – unlike coal, gas, oil, even burning wood, waste and biofuels – emit no carbon dioxide or other greenhouse gases. That alone is reason to build more of them to help meet the nation’s electricity needs. Currently 33 new nuclear plants are being planned, but unfortunately those additions won’t be enough to maintain nuclear power’s current share of electricity generation, let alone reduce U.S. greenhouse gas emissions. The Energy Information Administration recently forecast that by 2030 nuclear power’s share will decline from 20 percent today to 15 percent. Meanwhile, coal’s share of electricity production is projected to climb to 55 percent.

Until EPA or Congress deals directly with the carbon problem, it is likely that scores of coal plants will be built that we’ll all live to regret. The challenge will be to expand the use of nuclear power. It’s estimated that twice as many nuclear plants as now planned – about 60 – will need to be built over the next two decades in order to reduce greenhouse emissions to 1990 levels. It is well worth the effort if we want to prevent dangerous changes in our climate.

Donald A. Grant. Ph.D., P.E., is the R.C. Hill Professor and chairman in the mechanical engineering department at the University of Maine.