A recent study by scientists at the U.S. Department of Energy’s National Renewable Energy Laboratory (NREL) demonstrates that solar cells can be made more efficient through the application of nanotechnology. DOE researchers state that “quantum dots” can convert more than 65 percent of solar energy into electricity, which could roughly double existing solar cell efficiency.
- National Renewable Energy Laboratory. “Quantum Dot Materials Can Reduce Heat, Boost Electrical Output.” 23 May 2005 at www.nrel.gov/news/press/2005/1805_quantum_dot.html; Nano Letters at pubs3.acs.org/acs/journals/toc.page?incoden=nalefd
Quantum dots, also called “nanocrystals,” can produce more electricity than solar cells. While solar cells can convert one photon of solar energy to one electron (with the rest being lost as thermal byproduct), quantum dots can reduce heat waste and convert up to three electrons per sunlight photon.
Implications: The Laboratory’s research team suggests that quantum dots could make solar energy more efficient and cost-effective, critical if solar technology is to replace coal or gas as a power source at competitive market rates. In addition, the researchers have suggested that the technology could be applied in the future to photoelectrochemical cells, creating a renewable method for generating hydrogen – which might be used in place of gasoline as a mobile fuel source as well as a stationary source of electricity.
