When Chemical Plants Heat Homes: Industrial Waste Heat Becomes a Source of Energy
03.06.2026
When the heating comes on in the morning or hot water flows from the tap, very few people think of chemical production. Yet it is precisely there that thermal energy is generated every day, much of which has often gone unused until now. Initial projects are demonstrating how industrial companies can use this waste heat to supply households.
How it works:
- Industrial waste heat is generated during production processes, such as when cooling equipment or during chemical reactions.
- This energy is harnessed via heat exchangers or heat pumps.
- The heat is then fed into a district heating network.
- Households receive heating and hot water through this network.
A project by Henkel and Stadtwerke Düsseldorf demonstrates how industrial waste heat is already being integrated into the heating supply today. A new energy centre has been built on the factory premises in Düsseldorf-Holthausen, which feeds industrial waste heat into the district heating network.
Among other things, this involved laying a pipeline around 3.6 kilometres long to the surrounding neighbourhoods. The previously unused heat from production is processed via heat exchangers and then used to supply heat to households.
According to the project partners, this is expected to save around 6,500 tonnes of CO₂ annually. Above all, this example demonstrates one thing: industrial waste heat cannot simply be 'switched on'. For such projects to work, industrial companies, energy suppliers and local authorities must work closely together – technically, economically and in terms of infrastructure.
A project at the Evonik site in Herne goes one step further. There, Evonik and Uniper are using a high-temperature heat pump to convert industrial low-temperature waste heat into district heating. This is set to supply around 1,000 households.
The challenge: the cooling water from production initially reaches only around 25 to 30 degrees Celsius. This is not sufficient for conventional district heating networks. The heat pump therefore raises the temperature to up to 130 degrees Celsius.
The project demonstrates how important new heat pump technologies could become for industrial heat utilisation. This is because many existing district heating networks still operate with high flow temperatures.
Benefits of Using Industrial Waste Heat for Heating
Using industrial waste heat for heating offers a number of benefits for cities, energy suppliers and industry:
- Supplying households with climate-friendly heat
- Reduced use of fossil fuels
- Better utilisation of existing energy
- A new role for industry in local heating supply
Why isn't industrial waste heat used on a widespread basis for heating?
"Not every industrial plant generates waste heat in quantities, at temperatures, or with the availability required for external use. Furthermore, a heating network must either be located nearby or first be established at considerable expense. The construction of new pipelines, energy centres and transfer stations is complex, costly and subject to extensive regulatory approval processes. At the same time, such projects require long-term partnerships between industry, energy suppliers and the public sector. Planning, financing and implementation often take several years.
Industrial waste heat will therefore not replace the heat supply across the board, but where the conditions are right, it can become an important building block of the heat transition – particularly in cities and industrial regions."
Industry as Part of the Heat Transition
Projects such as those in Düsseldorf and Herne demonstrate the potential that previously untapped industrial waste heat offers for heat supply. This also opens up a new role for the chemical industry: not only as an energy consumer, but also as a potential source of energy for towns and local authorities.
In future, the heat transition could therefore take place not only in boiler rooms – but also behind factory gates.
Author: Elena Blume | K-Mag
Elena Blume has been writing for various industry magazines for eight years and joined the K-Mag editorial team in 2021. She is particularly interested in topics related to innovative plastics solutions that contribute to sustainability and address current challenges relevant to industry and society.
At a glance
- Chemical companies can increasingly feed surplus process heat into district heating networks.
- Heat pumps make even low-temperature waste heat usable for households.
- Projects in Düsseldorf and Herne demonstrate the potential of industrial waste heat for the heat transition.
Key Takeaway:
Industrial waste heat can heat households in a climate-friendly way – but for this to work on a large scale, the right infrastructure and cooperation are needed.