Using waste heat, heat that is a by-product of manufacturing or other energy-consuming processes, seems like a no brainer that would help conserve energy and limit the amount of greenhouse gas emissions generated by burning fossil fuels. One of the barriers to reusing waste heat is that in order to be recovered it needs to be at a very high temperature. According to the U.S. Department of Energy, 60% of waste heat is not hot enough to be reused. That is a considerable amount of wasted heat, which is dissipated into the atmosphere. What can we do to capture this low-temperature waste heat and reuse it in the United States?
Waste heat is everywhere. We can see it coming out of the sides of our houses, from our exhaust pipe when we heat our houses. Rather than letting it go to waste, the heat created from low-efficiency boilers in a home’s furnace room can be used to dry clothes and conserve the energy that would otherwise be used to fuel a clothes dryer. Some scientists have been researching how to use microwave technology to capture waste heat from cars and machines and turn it into energy. It is really the same concept as recycling paper or other materials. Recycling turns used materials that would otherwise be landfilled into new materials, and harnessing waste heat turns what would normally be lost into a new energy source—conceptually saving resources. The current limitations of using waste heat as an energy source are the science and cost.
If you start to notice all the waste heat entering the atmosphere as you drive down the highway, you can see how we are causing global warming. It does not take a room full of geniuses to tell us that global warming is a real phenomenon. Can we take this low-temperature waste heat and turn it into something? I guess we have to ask the geniuses sitting around the table.