Efficiency is one of the simplest and cheapest ways to reduce energy use and, in turn, reduce greenhouse gas emissions as prices continue to rise and concern over climate change grows.

The North American Energy Work Group was formed in 2001; it was followed by the North American Energy Security Initiative in 2006. Discussions of the NAEWG cooperative plan are expected to pick up in June, Energy Department officials said.

"This will make life easier for manufacturers of appliances, lighting products and electrical equipment," an Energy Department official said.

The program will focus on expanding the U.S. Energy Star program, sharing vehicle fuel-economy and other transportation-efficiency technologies among the three countries and integrating all three energy systems to increase savings, new technology and trade.

There's also an agreement on the private-sector side. The North American Competitiveness Council holds energy efficiency and sustainable energy technologies as some of its top concerns.

Aside from efficiency, the NAEWG will look at biofuels, hydrogen, clean coal and carbon capture and storage.