IN THE EARLY 1970s, before Chernobyl or Three Mile Island, before anyone was worried about climate change, the Danes decided to harness the wind and not the atom to generate much of their electricity. Today, the design and production of state-of-the-art windmills is this small country's biggest industry.

THE BEST way to tell which way the wind industry is blowing is to visit a wind farm built here two decades ago with 101 turbines that are now considered the antique Model As of the technology. As equipment fails in these small units, they are dismantled for scrap. Wind turbines are getting bigger and moving offshore.

ON VETERANS Day last year, an armistice was announced between two sides that had fought bitterly over how the United States would build air conditioners in the future. The agreement forged between air conditioner makers and advocates of efficient energy stands to spare US electricity producers the need to build 25 extra power plants by 2020.

THE BUSH administration still denies that manmade greenhouse gases are changing the planet's climate. But one sign of how serious environmentalists consider the threat of global warming is that some are calling for a new look at nuclear power, which emits no carbon dioxide in generating electricity.

HALF OF all the electricity in the United States is produced by burning coal, the fossil fuel that creates the most carbon dioxide. China, which trails only the United States in production of greenhouse gases like CO₂, also has large coal reserves and plans to build more than 500 new coal-burning power plants by 2012.

From the day four years ago when President Bush reversed his campaign pledge to limit carbon dioxide emissions by US industry, the federal government has ignored climate change, the greatest threat mankind has caused to the well-being of the planet. It falls now to the Senate to steer the country toward a more responsible course by including in its energy bill a cap on carbon dioxide emissions.