COOL DH – a pioneering project for district heating solutions

COOL DH Kick-off

Welcome to COOL DH! In this project, we will develop new and path-breaking solutions for district heating and demonstrate state of the art example of district heating systems that are adapted to a sustainable energy system.

COOL DH will innovate, demonstrate, evaluate and disseminate technological solutions needed to use sources of low-grade waste heat in a low temperature district heating-grid (LTDH-grid). The demonstration covers both new developments and stepwise transition of existing areas with district heating and energy retrofitting of buildings. The LTDH system developed by Kraftringen in Lund will be world’s largest. In short, COOL DH will:

  • Innovate, design and build cooling and heat recovery process systems, enabling heat recovery to a local low temperature district heating grid.
  • Design and build a low-temperature district heating grid with non-conventional pipe materials and testing of new innovative pipe components.
  • Innovate and design suitable heating systems and controls inside buildings that combine LTDH with distributed integration of local produced renewable energy from for example solar panels on the buildings.
  • Develop viable business models and new pricing systems, that ensures a good (low) return temperature and provide the building companies with maximum flexibility regarding the choice of heating systems.
  • Demonstrate a full system with all needed components suitable for ultra-low DH temperatures including demonstration of systems for heating of domestic hot water without risk of legionella.

Potential impact on a European level

According to Heat Roadmap Europe, about 6.000 utilities presently serves 13% of the heating demand in the EU. The amount of unexploited waste heat exceeds the amount of heat needed to heat up all the buildings in the EU. If waste heat would cover 50% of the heat demand for buildings, it could save 30 to 50 billion euro per year in purchase of fossil fuels, and replace 100% of the present use of natural gas used for heating buildings.

Since waste heat is available at different temperatures, which is often lower than needed in traditional district heating systems, COOL DH will have a big impact as it shows how to exploit low-grade heat sources as well.

We invite you to follow the progress

We hope that you find COOL DH interesting and invite you to follow our progress; we will keep you updated on this website. If you have any questions concerning the project, please contact project coordinator Reto M. Hummelshøj at

COOL DH Kick-off

COOL DH kick-off with mingeling participants in december 2017

Anders Almgren, Chairman of the Lund Municipal Council, greets the participants of COOL DH welcome at the project kick-off in Lund, december 2017.