While solar power theoretically has the potential to replacing significant quantities of fossil fuel power and reduce greenhouse gas emissions, building solar power plants takes a lot of energy, and currently most of this energy comes from fossil fuels. This problem, sometimes called energy cannibalism, falls under the general issue of energy return on energy invested.
The ‘solar breeder’ is an idea intended to overcome this problem. A solar breeder is a solar power plant that uses its own energy to build more solar power plants of this kind. Such a plant could become not only energy self-sufficient but a major supplier of new energy. In theory it can reproduce exponentially, hence the name ‘breeder’.
Research on the concept was conducted by Centre for Photovoltaic Engineering, University of New South Wales, Australia. For an analysis, see:
J. Lindmayer, The solar breeder, in: Photovoltaic Solar Energy Conference, Luxembourg, September 27-30, 1977, Proceedings, D. Reidel Publishing Co., Dordrecht, 1978, pp. 825-835. Abstract available online.
J. Lindmayer, Solar breeder: Energy payback time for silicon photovoltaic systems. Abstract available online.
The abstract of the second article above reads:
The energy expenditures of the prevailing manufacturing technology of terrestrial photovoltaic cells and panels were evaluated, including silicon reduction, silicon refinement, crystal growth, cell processing and panel building. Energy expenditures include direct energy, indirect energy, and energy in the form of equipment and overhead expenses. Payback times were development using a conventional solar cell as a test vehicle which allows for the comparison of its energy generating capability with the energies expended during the production process. It was found that the energy payback time for a typical solar panel produced by the prevailing technology is 6.4 years. Furthermore, this value drops to 3.8 years under more favorable conditions. Moreover, since the major energy use reductions in terrestrial manufacturing have occurred in cell processing, this payback time directly illustrates the areas where major future energy reductions can be made – silicon refinement, crystal growth, and panel building.
BP Solar originally intended its plant in Frederick, Maryland to be a solar breeder, but this plan was cancelled:
More recently, the following institutions in Japan
University of Tokyo
National Institute for Material Science
Tokyo Institute of Technology
National Institute of Informatics
have teamed up with the Université des Sciences et la Technologie d’Oran (USTO) in Algeria, and launched a joint initiative called the Sahara Solar Energy Research Center (SSERC). Commonly called the Sahara Solar Breeder Project, it claims to have the incredibly ambitious goal to “build enough solar power stations by 2050 to supply 50 per cent of the energy used by humanity”. The plan is to build a solar breeder in the Sahara desert, and convert sand there to silicon wafers used in solar panels:
Michael Fitzpatrick, Sun and sand breed Sahara solar power, New Scientist, 30 November 2010.
Diginfo, The Sahara Solar Breeder Project, YouTube.
The project appears to be led by Hideomi Koinuma from the Science Council of Japan, who proposed the idea at the 2009 G8+5 Academies’ Meeting in Rome:
Despite many news reports on this project, details seem hard to find, so it is difficult to tell how seriously to take it.