Fueling the energy transition with waste heat

One sixth of the district heating that Adven delivers in Sweden on an annual basis comes from industrial waste heat*. The company has specialized in both industrial solutions and district heating for decades, and there are new residual heat projects arising every year.

— Residual heat is not free, but there are enormous values to be gained for the benefit of the climate, but also for the industrial sector and society, says Lars Sjökvist, residual heat expert at Adven.

Sweden is currently the best in Europe at recovering residual heat, largely due to a well-developed district heating system. Despite this, the Swedish Energy Agency estimates that there is a residual heat potential of an additional 110–170 TWh annually. Here, the Swedish Energy Agency calculates, the majority will come from industrial investments in the steel industry and from biofuel production, but there is also great potential in the chemical and cement industries.

The energy transition comes in many shapes. Electrification is one. Using energy smarter is another, and this is where district heating comes into the picture. Adven operates around fifty small and medium-sized district heating networks around the country – a prerequisite for taking a load off of the electricity grid, but also a key to being able to spread valuable residual heat from various industrial processes.

— Today, every second household in Sweden is heated with district heating, and the amount of waste heat that is expected to be available in 2045 in theory covers that need twice as much,” says Lars Sjökvist.

In practice, it is more difficult to realize the potential. One reason is that the temperature of the waste heat is sometimes too low, another is that the waste does not always occur where the heat is needed. Through close collaboration with industry, where Adven designs the entire energy system – including upstream in the industrial process – the company has nevertheless been able to increase the volume of residual heat every year.

In Hofors, the steel manufacturer Ovako has built Sweden’s largest plant for fossil-free hydrogen. This made the company the first in the world to heat steel for rolling without the use of fossil fuels. Even before that development step, Adven was making use of about 25 GWh of waste heat from its industrial processes – energy that is distributed to the district heating network and corresponds to the heating needs of about 1,250 houses per year. The new electrolysis plant provides an additional 3-9 GWh of waste heat annually. Adven is involved in residual heat collaborations like this with industries in eight places around Sweden, and a few more in Finland, a figure that the company intends to grow continuously.

— The more people who realize that residual heat pays off and stop squandering it, the more electricity and biofuel there will be available for the energy transition,” says Lars Sjökvist.

*Waste and residual heat are used here synonymously

For more information:

Lars Sjökvist, Concept Developer Adven, +4670 693 47 98, lars.sjokvist@adven.com

Jonas Dyrke, Business Project Developer Adven, +4670 666 52 25, jonas.dyrke@adven.com