The United States throws away a staggering amount of energy that could be cheaply and easily captured and used, according to the latest issue of World Watch magazine.

Waste-energy recycling—which captures smokestack waste and other wasted energy and puts it to work—currently contributes about 10,000 megawatts of electric power to the U.S. national total each year. But a recent study estimates that if the energy content of all U.S. smokestack waste were recycled, it could replace roughly 30 percent of the electricity produced by burning fossil fuels. Elsewhere the technology is widely used: Russia gets over 30 percent of its electricity from waste-energy recovery, while Denmark gets more than 50 percent.

In “Bridge to a Renewable Energy Future,” co-authors Robert Ayres and Ed Ayres explore this underutilized technology and its ability to bridge the transition from fossil fuels to renewable energy sources, noting that expanding these technologies is often a boon for the investor’s bottom line as well as the environment.

“As atmospheric levels of carbon dioxide also rise—and as public concerns about the global energy dilemma also rise—private investment in the energy transition bridge may shift from tentative to robust,” they write. “The key…is that in many cases, such investments can bring the double dividends of both corporate and social benefits, often with a rapid return on investment.”

Despite their potential, these proven technologies have been seriously underused to date. And energy recycling is just one of several high-potential strategies that can reduce both fossil-fuel use and carbon emissions during the long transitional period ahead.

“Waste-energy streams aren’t a substitute for renewables, of course; the point is we’re going to need both. And energy recycling from fossil fuel-burning plants can help us make the transition to renewables much sooner.”