Photovoltaics, or PV for short, is a solar power technology that uses solar cells or solar photovoltaic arrays to convert light from the sun directly into electricity. Photovoltaics is also the field of study relating to this technology and there are many research institutes devoted to work on photomontages. The manufacture of photovoltaic cells has expanded dramatically in recent years. Total nominal 'peak power' of installed solar PV arrays was around 3,700 MW as of the end of 2005, a 42% increase for the year, and most of this consisted of grid-connected applications. Such installations may be ground-mounted (and sometimes integrated with farming and grazing) or building integrated. Financial incentives, such as preferential feed-in tariffs for solar-generated electricity and net metering, have supported solar PV installations in many countries including Germany, Japan, and the United States.
Unlike fossil fuel based technologies, solar power does not lead to any harmful emissions during operation, but the production of the panels leads to some amount of pollution. Also, placement of photovoltaics affects the environment. If they are located where photosynthesizing plants would normally grow, they simply substitute one potentially renewable resource (biomass) for another. It should be noted, however, that the biomass cycle converts solar radiation energy to electrical energy with significantly less efficiency than photovoltaic cells alone. However, if they are placed on the sides of buildings (such as in Manchester) or fences, or rooftops (as long as plants would not normally be placed there), or in the desert they are purely additive to the renewable power base.
