The more the sun shines, the colder it gets.

As we all know, the biggest energy source of all is the sun. The problem to date has been to make big systems profitable.

But now things are beginning to happen. Developments are being driven by the knowledge that energy will get more expensive. Renewable energy sources must be developed. Närvård Härnösand (formerly Härnösand hospital) now has the world’s first solar energy plant that produces electricity, heat and cold simultaneously.

The Foundation for Research into Concentrated Solar Energy (Stiftelsen för forskning om koncentrerad solenergi) and the Härnösand-based company Absolicon are behind this unique demonstration plant.

On the roof of the house are solar panels that subtly track the altitude of the sun during the day. The display room contains the heart of the system that converts heat into cold.

The system consists of a tank containing dry salt and a tank containing water. By lowering the pressure in the water tank, the water evaporates and the tank becomes cold as the energy is removed. The building is then cooled with the cold from the cold water tank.

In the other tank, water vapour fuses with the salt, which becomes hot. The salt is then dried by the salt tank being heated with solar heat. The water is released from the salt and condenses in the water tank. When the salt is dry, the process can start again, and again, and again…

Sun-worshippers have always existed. Now it is cooler than ever to be one!