Future PV systems to produce water and AC
Published: Oct 29, 2013
A promising research project out of Switzerland is set to re-shape how we think of and use photovoltaic systems that we typically think of as helping us to save on energy costs and improve our carbon footprints, showing that new systems in the pipeline might be capable of much more.
Even the greatest of skeptics would take a second look at this collaboration between IBM Research, Airlight Energy, ETH Zurich and Interstate University of Applied Sciences Buchs NTB, that have received a three-year, $2.4 million grant to develop a high concentration photovoltaic thermal (HCPVT) system that boasts of being more economical than any other in development.
What sets this system apart and makes it important to us here in The Bahamas is its application for use on remote tourism locations primarily due to the system’s ability to also provide potable water and air conditioning.
The prototype of the HCPVT is apparently capable of concentrating the solar radiation it captures by some 2000 times and successfully converts 80 percent of the radiation into useful energy.
The array is fashioned into a large parabolic dish, with a look that is very similar to the large satellite dishes used for TV reception back in the 80s, and utilizes hundreds of chips that are one centimeter by one centimeter in size, with each being able to convert 50 watts.
This results in a receiver that provides an impressive 25 kilowatts of power.
Interestingly enough, the system is kept cool through a direct cooling system with very small pumping power that mimics the blood supply system of the human body.
If all of that does not impress you, you should be convinced by a cost to produce electricity that is set to be less than 10 cents per kilowatt-hour. Ours in The Bahamas is currently around 40 cents per kilowatt-hour.
In any solar PV array, overheating of the cells is a concern. This HCPVT system, rather than being designed to dissipate heat to the environment, is set to capture the heat using systems developed for keeping high performance computers cooled.
This micro-technology, as it is referred, uses water to remove the heat from the chips. This 90°C water is in turn used in a desalination process. The larger the PV installation, the greater the production of water.
Another really big plus for application in remote tourism resorts is the use of the HCPVT system to produce air-conditioning by means of absorption chillers. One big benefit here is that water rather than refrigerant is the working fluid and this is much safer on the environment.
This research project demonstrates what has be long accepted in the renewable energy industry – that increased investment in research is the only way to arrive at a point where renewable energy production becomes competitive to traditional forms.
• We would like to hear how this article has helped you. Send questions or comments to firstname.lastname@example.org. Sonia Brown is principal of Graphite Engineering Ltd. and is a registered professional engineer.