For decades, investment tax credits have helped speed up solar and wind development by lowering costs. Now, they could do the same for another form of carbon-free energy that became eligible for a 30 percent tax credit for the first time ever. It’s called waste heat to power, or WHP.

In the U.S., about 67 percent of our energy is squandered. Various inefficiencies in power plants, vehicles, factories, homes, and countless other places mean the majority of the energy we have access to is lost, often as hot air, or “waste heat.” But you know what they say — one man’s waste heat is another man’s untapped source of clean energy. WHP systems take some of that squandered heat and turn it into electricity, which can either be used on site or sent back to the grid.

“It’s a really terrific source of energy because there are no new emissions that are produced as a result of using it,” said David Gardiner, executive director of the Combined Heat and Power Alliance, which lobbied for the new tax credit. “You’re simply capturing the waste and putting it to good use”

With today’s technology, the best sources of waste heat that can be turned into electricity are industrial processes that release heat that’s at least 450 degrees F. A 2015 market assessment prepared for Oak Ridge National Laboratory found 96 existing WHP systems that generate a total of 766 megawatts of power, similar to the capacity of a single gas-fired power plant. Most of these systems are installed at chemical plants, refineries, and steel mills. There are also several WHP systems at compressor stations along natural gas pipelines. Many states have encouraged the technology by allowing it to qualify as clean energy under policies that set minimum renewable energy mandates such as renewable portfolio standards.

There’s potential for much more: The report identified almost 3,000 additional facilities in the U.S. that could install WHP equipment and generate another 8,840 megawatts of electricity, or roughly half the average hourly demand in New York state.