Text  Svein Tønseth, SINTEF Media 
Photo  Mette K. Høiseth

It took a long time to organize a conference dedicated to Professor Gustav Lorentzen (1915-1995). But the event was realized for the first time in Trondheim from 28 to 31 May 2006 in the city where he lived and worked.

Using natural materials
Traditionally, chemicals were used in air-conditioning systems and heat pumps but if there was a leakage this could lead to depletion of the ozone layer. This was a serious matter that led to an international agreement in 1987 that such CFC gases should be banned. The chemical industry soon came back with a new chemical replacement, but independent tests revealed that this had negative greenhouse effects.

This was when Professor Lorentzen decided to avoid chemicals and use one of nature’s own materials – CO₂ – as the “work horse” in heat pumps and air-conditioners. It was a sustainable solution, because the CO₂ was “borrowed” from industrial emissions that that would otherwise just be emitted into the atmosphere.
 
Coming in future cars
Together with close colleagues at SINTEF and the university, Lorentzen started work that has now resulted in a series of patents in the operation, control and design of CO₂ units. Researchers in Trondheim were the first to find that CO₂ could replace chemicals in car air-conditioners without increasing fuel consumption.

The European Commission is now preparing regulations stating that all new car models from 2011 onwards must have air-conditioners without chemicals. Car factories already have test-cars on the road with CO₂-based air-conditioners. At the same time SINTEF and NTNU are participating in a European Commission project aiming at designing simple and inexpensive CO₂-based air-conditioning units for small cars.

Japanese bath water and Coca Cola
The CO₂ technology that was discovered in Trondheim has made its way into several other areas. CO₂ technology from SINTEF and NTNU has become a hit in Japanese homes. Here it is being used in heat pumps for heating tap water and indoor air.

At the same time Coca Cola has announced that the mega-concern will start using CO₂ technology in all of their soft drink chillers worldwide.

European Commission against chemicals
The scientific conference that honoured Professor Lorentzen was arranged for the 7th time this year. The venue was the Natural Science Building at the Norwegian University of Science and Technology in Trondheim. The International Institute of Refrigeration organized the conference.

Speakers included the European Commission’s Matti Vainio, who has been central in the Commission’s work to phase out of today’s chemicals in air-conditioning systems in cars. The former Norwegian Minister of the Environment, Børge Brende, who is now the deputy chair of the parliamentary Energy and Environment Committee, held the introductory presentation.

There was no need to ask Børge Brende twice, he jumped into the driver’s seat in an Audi A4 test-car with CO2-based air-conditioning technology. The Commission is considering banning the use of chemicals in air-conditioners for new cars from 2011 onwards, and CO2 may be chosen as the alternative. On the right, SINTEF researcher Petter Nekså.