Also, carbon dioxide and nitrogen oxide emissions increase when the additional coal is burned.

It would also cut nitrogen oxide emissions by 2 million tons, or about 1 percent.

By 2003, the Bush plan aims to cut nitrogen oxide emissions, a component of smog, in half.

The 717,000 tons comes to about 5 percent of all nitrogen oxide emissions from the states, according to the agency.

Fuel Cells also produce 97% less nitrogen oxide emissions than conventional coal-fired power plants.

Sixty percent of the nitrogen oxide emissions come from vehicles, the group estimates.

Mobile sources are responsible for more than half of all nitrogen oxide emissions in the United States.

It will also reduce nitrogen oxide emissions, which contribute to smog, by 90 percent, or 17,000 tons a year.

Forty per cent of nitrogen oxide emissions in Britain come from vehicles.

Measures have been taken in Europe to control sulphur dioxide and nitrogen oxide emissions since the 1970s, with some success.