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TECHNICAL
EYE
distribution to customers.
But the project is mainly for demonstration purposes and for gaining experience in operating such a system in the future. The cost of solar photovoltaic electricity is approximately 15 times that of conventional sources. But such systems are being used extensively in the southwestern states, where low humidity and lack of a cloud cover make the effort more economically feasible.
Throughout Virginia, however, small scale solar devices introduced in the 70s are quite common and remain in use. They are found routinely in multi-unit residential areas, nursing homes and hospitals, apartment complexes, and various industries. Just check out the rooftops.
The systems are either active or passive. Active systems consist of a solar collector, a storage facility, and a pump or fan to distribute the stored energy. They are generally used to heat hot water. Passive systems incorporate glass panels or windows with a southern exposure, admitting thermal energy much like a greenhouse and circulating it with the room air. Hybrid systems combine both active and passive features.
Archimedes used solar energy to defend Syracuse against the Romans, setting the invading ships afire with a system of mirrors. Indians of the American southwest relied on passive solar designs in the construction of their cliff-dwellings. Today, satellites are powered by solar cells, and a solar-powered aircraft has flown the English Channel.
With such history, solar technology is sure to continue. You can bet your tan on it.
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