Power
Solar generation
Photovoltaics and other methods of converting sunlight to electricity
There are several accepted ways of converting solar radiation to electrical power.
Photovoltaics
The sun’s energy can be converted directly into electricity using photovoltaic cells. PV cells can be used for applications as small as watches and calculators, to large grid-connected arrays of panels. The great attraction of PV technology is that it delivers electricity at the point of use, for example panels can be integrated into buildings to supply the buildings themselves.
In areas where grid connection or other forms of generation are too expensive or not feasible, PV can be very cost-effective. This may be in remote locations, but could also be in a city centre where grid connection may be impractical. For example it can be cheaper to power parking meters with solar energy than with power from the grid.
PV materials are usually solid-state semiconductors. various forms are used:
- Mono-crystalline silicon
- Poly-crystalline silicon
- Amorphous silicon thin film
- Thin film cells of other materials such as copper indium diselenide (CIS) and cadmium telluride
- Organic solar cells
Other technologies are also under development
Solar thermal power generation
Technologies also exist to collect the sun's heat and use it generate steam, which then produces electricity using a conventional turbine.
One notable example of this approach is the solar 'power tower' approach where fields of mirros are used to focus the sun's rays onto a boiler at the top of a tower.
