Environmental Engineering Reference
In-Depth Information
Solar
DOE's solar R and D program is working to make solar energy technologies a
more cost-competitive source of electricity. Specifically, DOE's extensive work
has advanced solar technologies, improved efficiency and reliability, lowered
costs, and resulted in more than 235 patents. While solar energy technologies have
evolved and costs have decreased, DOE is focused on further reducing solar
energy costs to compete in the residential, commercial, and industrial energy
markets and for solar technology to penetrate the market sufficiently to create a
sustainable solar industry. Currently, DOE's solar R and D program focuses on
developing advanced photovoltaics, also called solar cells, that produce electricity
directly from absorbed photons from sunlight; solar heating and lighting systems;
and utility-size, solar-power plants.
DOE's photovoltaic R and D program is designed to increase performance,
reduce costs, and enhance the reliability of photovoltaic systems. DOE initially
focused on using crystalline-silicon, which continues to hold the majority of the
photovoltaic market today. DOE's second generation of photovoltaic R and D
focuses on thin-film technology, which is designed to use less materials to reduce
costs and can be made into a variety of forms. DOE's goal is to lower the cost of
photovoltaics so that they are an affordable alternative to traditional electricity
sources across all sectors. DOE is working to reduce the costs of photovoltaics
from about 18 to 23 cents per kilowatt-hour in 2005 to about 5 to 10 cents per
kilowatt-hour by 2015.
DOE's solar heating and lighting R and D program is developing
technologies that use sunlight for various thermal applications, particularly space
heating and cooling, water heating, and to illuminate building interiors. DOE's R
and D program is focused on advancing materials, design, and manufacturability
that will lower costs of solar water heaters, improve their performance, and ease
installation. DOE seeks to reduce the costs of solar water-heating systems
operating in cold climates from about 11 to 12 cents per kilowatt-hour today to
about 5 to 6 cents per kilowatt-hour by 2011. DOE is also working with industry
to fully commercialize solar lighting systems. However, the administration's
fiscal year 2007 budget proposed eliminating funding for the solar heating and
lighting R and D program.
DOE is also working with industry and southwestern states to develop utility-
size solar power plants that use two types of concentrating solar power
technologies: trough systems and dish/engine systems. These technologies use
various mirror configurations to convert the sun's energy into high-temperature
heat that is used to generate electricity in a steam generator. DOE's goal is to
