Franco-Israeli collaboration aims to develop floating solar power plants
Soon after the design phase was over, at the end of March 2010, the fabrication of a prototype began and the team is now aiming to launch the implementation phase in September 2011.
The tests will take place at Cadarache, in the South East of France, the site having a privileged position on the French electric grid and being close to a local hydro-electric facility providing the water surface to be used for the installation of the system. The system will operate on-site during a period of nine months, while assessing the system’s performances and productivity through seasonal changes and various water levels. The research team members believe that by June 2012, they will have all the information required to allow the technology’s entry on the market.
As even leading photovoltaic companies struggle to find land on which to install solar power plants, the project team identified the almost untouched potential of solar installations on water. The water basins, on which the plants could be built, are not natural reserves, tourists’ resorts or open sea; rather they are industrial water basins already in use for other purposes. By that, it is assured that the new solar plants will not have a negative impact on natural landscapes.
"It’s a win-win situation", declared Dr. Kassel, "since there are many water reservoirs with energy, industrial or agricultural uses that are open for energy production use".
After solving the question of space, the team also took on the problem of cost. "It sounds magical to combine sun and water to produce electricity, but we also have to prove that it carries a financial logic for the long run", explained Dr. Kassel. The developers were able to reduce the costs linked to the implementation of the technology by two means. First they reduced the quantity of solar cells used thanks to a sun energy concentration system based on mirrors, while keeping steady the amount of power produced.
Secondly, the team used a creative cooling system using the water on which the solar panels are floating. Thanks to this efficient cooling method, the photovoltaic system can use silicon solar cells, which tend to experience problems linked to overheating and need to be cooled down in order to allow the system to work correctly, unlike standard type more expensive cells. The particular type of solar cell used also allows a higher efficiency than the standard ones, achieving both reliability and cost reduction.
Still for the purpose of making the technology efficient and ready to market, the system is designed in such way that on a solar platform it is possible to assemble as many identical modules as needed for the power rating desired. Each module produces a standard amount of 200 kiloWatt electricity, and more power can be achieved by simply adding more modules to the plant.
The team also worked on the environmental impact of the technology which as a breathing surface through which oxygen can penetrate to the water. This feature ensures that sufficient oxygen will maintain the underwater life of plants and animals. Dr Kassel said: "One of the implementation phase’s goals is to closely monitor the possible effects of this new technology on the environment with the help of specialists" and "a preliminary check shows no detrimental environmental impact on water quality, flora or fauna. Our choices of materials were always made with this concern in mind".
Dr. Kassel sees to his project a last benefit: "Today, each country must consider the best resources it has in order to produce clean energy. For example: hydroelectric power is good where there are waterfalls, geothermic is productive for countries with thermal springs and solar power is very efficient where there is sun. Our system could be of great use in places that are exposed to sun, but not necessarily have sufficient natural water. Even dry countries, such as Israel or the North African countries, have industrial waters that are not rain dependent. This fact makes the floating solar power plant a reliable method for them to produce renewable energy".