Fixing the Energy Crisis: The U.S. Is Sitting on a Gold Mine of Excess Heat

According to new data from multi-national engineering group Danfoss, excess heat is the world’s largest untapped source of energy and yet little of its potential is being used, especially in the United States.

Every time an engine or machine runs, it generates heat. Anyone who has felt the warmth behind their refrigerator recognizes that. The same is true on a larger scale in supermarkets, data centers, factories, wastewater facilities, subway stations,  and commercial buildings. Excess heat can be reused to supply a factory with heat and warm water or exported to neighboring homes and industries through a district energy system which supplies heat to consumers via a network of underground pipes carrying hot water. Such heat networks can cover a large area or even an entire city or supply a small cluster of local buildings.

While the U.S. would need to invest in infrastructure and district heating systems, there is low-hanging fruit in universities and hospital campuses to apply this solution now.

According to Astrid Mozes, President, Regions, at Danfoss, recycling heat is not only an overlooked measure in the current energy crisis but also the next frontier of the green transition in the United States:

“The United States is sitting on a gold mine of excess heat. Excess heat is the world’s largest untapped source of energy and it is all around us. Using gas or electricity for heating is like using a chainsaw to cut butter, as heating can easily be covered by low-value heating sources such as excess heat. Despite this incredible opportunity – we have the most data centers in the world - there are very few initiatives pushing for more efficient use of the vast amounts of wasted energy in the form of excess heat. And this is even though we already have the solutions available to harness heat. We urgently need new policy measures to accelerate the use of excess heat across the U.S., both so that citizens and businesses can benefit from lower energy costs and to ensure we speed up our progress in the green transition and decarbonize our economy. Let’s make it happen."

Using excess heat can replace significant amounts of fossil fuels that are otherwise needed to produce heat. Used this way, excess heat can help stabilize the future electricity grid and thereby ease the transition to a green energy system. Yet the potential of excess heat is not even close to being utilized and is virtually ignored in policy circles.

Energy Efficiency In Its Purest Form

The whitepaper, The World’s Largest Untapped Energy Source: Excess Heat assesses the potential of excess heat as an efficient energy source. According to the International Energy Agency (IEA), a global push for more efficient use of energy can reduce CO₂ emissions by an additional 5 gigatons per year by 2030 compared with current policy settings. A third of the reduction needed in energy-related CO₂ emissions this decade must come from improvements in energy efficiency, according to the IEA net-zero scenario.

A full implementation of technologies that tap into synergies between different sectors and enable a utilization of excess heat has the potential to save USD 72bn (EUR 67.4 bn) a year once fully implemented in 2050.