Category 18 April 2019

24/7 heating and cooling from highly efficient solar collectors

Climatewell offers high efficiency solar energy solutions that also address the problem of the solar energy’s intermittency.

The challenge

Solar power, including power from solar thermal technologies, is fast becoming a major source of clean energy. However, producing energy from the sun via thermal conversion has its disadvantages. Heat is usually the output and it works best when the sun is shining the most, i.e. when the demand for excess heat is low. Electricity, heat and cooling are demanded at all hours, but panels do not produce energy during night time or when the sun is shaded from clouds etc. Existing storage solutions such as heat accumulators suffer from energy losses and spatial inconvenience.   

The innovation

Climatewell has developed a product that addresses solar thermal’s disadvantages with a simple and stable solution. By integrating a chemical heat pump device directly into the collectors and directing the energy in two circuits, both cool and heat can be provided. A small accumulator is also integrated in order to provide energy when sun is not shining. Direct integration provides the solution with an energy efficient design. The technology is a further development of an absorption technology wherein heating causes pressure differences in salt and liquid to create a chemical compressor that can be utilized as a heat pump. Climatewell has integrated the technology within thermal solar collectors and added the ability to control the flows in the system so that the salt can store energy that is not immediately used.      

Why did it work?

The knowledge base for the innovation started during the seventies when inventor Ray Olsson performed experiments to develop an energy storage unit based on salt. This didn’t succeed and the plans were put on hold until in the end of the nineties when Ray’s wife Mona began to write her thesis on energy storage within heat pumps. Olsson, who proof read his wife’s thesis, found some obvious mistakes but after a second thought he realized that his wife was onto something. He started experimenting and then in 2001, he met Göran Bolin, an innovator and entrepreneur, and the team structured their experimentation further. The breakthrough came in 2005 and they could present a functional prototype. At this time the product was an external device meant to be linked with some heat source, e.g. solar collectors. The device was however expensive and complex to handle and after some further development and testing the team changed the core product and integrated it into the solar collectors themselves. Development has been funded by venture capital for development, demonstration and commercial exploitation, since the early phases. Additional funding has included Public grant partial funding for R&D and Public grant funding for demonstration from the Swedish energy agency and Almi invest. The collectors were tested and verified by the Fraunhofer ISE institute in 2012 and rate between TRL 8-9 in terms of technological readiness. 

Further development

Climatewell has recently started a project to demonstrate the panels in a larger scale on top of an office building in Karlstad, Sweden. Funding comes partly from the European Union as it is a life plus project. Moreover, global contacts are being taken and markets such as the US, Australia and Asia are of particular interest.