WS 3 – Industrial heat pumps, the next phase

Industrial heat pumps, the next phase’, focuses on increasing the knowledge of heat pump technologies and the way to apply these to industrial processes beyond the traditional way of approaching in order to close the production cycles and reduce the amount and level of excess heat. By using the latest technologies, working fluids and software models, we are looking into the opportunities for electrification of the energy supply of the chemical industry.

The workshop brought together the different stakeholders that are involved in the development and implementation of industrial heat pumps. The main question was “what is needed to bring the industrial heat pumps to the next phase, i.e. to accelerate the use of heat pumps in industry?” The introduction about the (changing) role of heat pumps in industry highlighted Electrification as an important development that will provide opportunities for large scale implementation of heat pumps. Two consultants presented examples about Sustainable steam and Heat from Cold that showed that industrial use of heat pumps is feasible and already applied in certain (temperature) areas.

Then 4 major companies (Cargill, Heineken, Smurfit Kappa and DOW) challenged the audience to come forward with solutions for possible heat pump applications in specific processes:

  • Case 1 – presented by Norbert Koot from Cargill Industry
  • Case 2 – presented by Chris Versteegh from Heineken Brewery
  • Case 3 – Presented by Ton van Haasteren from Smurfit Kappa paper and pulp industry
  • Case 4 – Presented by Cees Biesheuvel from DOW Chemical

At the Conference there was a great number of presentations on industrial heat pumps and waste heat under Track 3. Although the use of waste heat is often considered at policy level as an important source for Distict Heating it is more obvious to use the residual heat first in the industry itself, then only to use it for heating homes. “If industry is to use heat pumps on a large scale, this will achieve our goal faster in reducing natural gas consumption and CO2 emissions, without having to invest in fine distribution grids and expensive heating systems.” A first most logical step therefore to this challenge of excess heat is to reuse the heat within the same process through process integration or at the same site. In an ideal process that will be within the process unit, otherwise technology will have to be applied to transform the heat coming out of the process to a common carrier. This being high pressure steam by a high temperature heat pump or or electricity generated by an ORC.

Should we take electrification into account when we develop heat pumps?

General opinion: yes, heat pump technology will be important for electrification of industry and vice versa, and intermittency should be taken into account in HP development.

The landscape of power generation is changing drastically in the next decades

The key challenge in achieving a carbon-neutral energy and production system is to decarbonise the sectors that are currently heavily dependent on fossil fuel resources, such as oil and natural gas. The most promising option for future decarbonisation of final energy and feedstock use in the chemical industry is to convert the relatively abundant potential of wind and solar energy – produced in the form of electricity – into heat, chemicals and fuels. Electrification has the potential to realise major progress on sustainability and reduction in fossil energy and feedstock use.

The shift from fossil to renewable sources will be accompanied by a shift from centralised generation of electricity in high capacity power plants to decentralised generation with more low capacity locations. Wind and solar energy are mainly harvested as electricity, by means of wind turbines and photovoltaic (PV) solar cells. The supply of these renewables fluctuates continuously and is non-controllable. With increasing shares of renewables in the total electricity production, the magnitude of fluctuations is increasing.

Both effects result in a growing need for flexibility in the electricity system.

Steam recompression for all high temperature applications?

Steam recompression is certainly a very important technology, but not applicable under all conditions. This was also illustrated in the presentation by DOW which showed that choosing a technology is indeed a very complex process that does depend on many non-technical issues. The answer to the question “why are heat pumps not more widely implemented at the moment?” was essentially: still too expensive. This was confirmed by the end users Cargill, Heineken, Smurfit Kappa and Dow, who added “reliability” as a second important aspect. They all are considering (demonstrations of) heat pump applications (mainly for steam production) or steam recompression and stated that they need to have a better business case and reliable heat pumps. Interesting note by them: more important to have the heat pumps available for pilots/ demo’s on a short term and to improve them on the go, than to have to wait until the technology is perfected.

Main conclusions

There is a growing interest for using heat pumps (power to heat) in the industry, but there are still bottlenecks:

  • The economics for heat pumps in the industry are not (yet) good enough to promote broad use.
  • Using heat pumps in core processes poses questions about risk and controllability. These need to be addressed by demonstrations.
  • For end-users, it is more important to have the heat pumps available for pilots/ demo’s on a short term and to improve them on the go, than to have to wait until the technology is perfected
  • At the moment end users are mostly looking at implementing heat pumps in existing installations (brown field). This brings extra complexity and the need for tailor made solutions.

An interesting Journal has been published to support the focus of the workshop: Dutch Heat Pumping Technologies Journal Vol 2