To lower industrial carbon emissions by means of high temperature heat pumps


The COMTA project proposes the thermo-acoustic heat pump as a solution

The industry is a large consumer of energy and about two-thirds of the industry’s energy use is represented by heat. Often high-temperature heat is required, this heat is currently provided by burning natural gas. In order for the industry to meet the climate goals we will need to move to low carbon heating systems. One way to achieve this is by implementing high temperature heat pumps. These heat pumps, however, are not yet commercially available. The COMTA project proposes to start using the electrically driven thermoacoustic heat pump for industrial purposes. It can deliver heat of up to 200°C and it can cover a very wide range of temperatures with a fixed standardized design. Because this heat pump is electrically driven, it will become completely carbon free once fully renewable electricity supplies have become a reality in the future.

Objective and approach of the project

The overall project objective is to further develop the compact electrically driven thermo-acoustic heat pump technology and to prepare it for technical demonstration on a full scale. Experimentally, heat delivery by means of steam production over a wide interval range (between 100 and 200°C) will be demonstrated using residual heat (between 50-150°C). These experiments will be performed under simulated (in Petten) and onsite test conditions at DOW in Terneuzen. A single full scale modular design will subsequently be realized that can cater to a wide market including the (petro)chemical industry, the refining industry, the paper and the food industry. Because of its modular design and its flexibility the thermal duty and temperature of the steam produced can be matched to the operational power and temperature requirements of the process.

Comta - Thermostat

The COMTA test set-up under operational conditions

The COMTA project will be the last stop on the way to realizing full scale demonstration projects of the thermo-acoustic heat pump. The remaining research and development will focus on improving the efficiency, it will concern optimizing the membranes and the heat exchangers. This will be tested by means of experimental component testing within the existing COMTA test set-up. Integration into the DOW steam utility and the onsite testing will verify the technical feasibility under real operational conditions. The realization of the full scale design will then be used for the verification of a techno-economic feasibility study and to prepare for the full scale testing in following demonstration projects.

Potential savings and results

The technological developments in this project will result in a net primary energy saving potential of 97 PJ per year and a potential CO2 emission reduction of 4.5 million tons/year within the Dutch food; paper & board; bulk chemicals and refinery sectors. Another major fuel cost savings for the Dutch industry overall amounting to 4.8 billion Euros can then also be realized. Renewable electricity systems that generate carbon free electricity in the future would result in even higher CO2 emission cuts of up to 9.4 million tons/year making this project a significant contributor to a fully sustainable and carbon free future for the Dutch industry. Partners in this project are: ISPT and TNO, and industry partners DOW, Bronswerk Heat Transfer and Howden Compressors B.V.


This project is co-funded with subsidy from the Topsector Energy by the Ministry of Economic Affairs and Climate Policy.