Photovoltaics is the field of technology concerned with the use of solar panels to provide energy. Photovoltaics has recently gained popularity because of a growing desire for clean and renewable energy. Solar panels work by converting the ultraviolet (UV) radiation in sunlight to electricity and produce no emissions. Sunlight is also a virtually endless resource, unlike fossil fuels.
In photovoltaics, solar cells made of silicon or other semiconducting materials are arranged into larger photovoltaic modules or panels, which in turn are combined in even larger photovoltaic arrays. Solar cells absorb the energy from sunlight, and electrons become detached from their atoms in the process. The electrons are then used to produce electricity. Photovoltaic arrays are often designed to cover otherwise unused areas exposed to a lot of sunlight, such as rooftops or large stretches of unused land, like a desert. Sometimes, photovoltaic arrays are designed to capture the maximum amount of sunlight by moving throughout the day, turning to face the sun as it moves through the sky.
Because of the recent popularity in renewable alternative energy sources, the field of photovoltaics has grown. One of the most important current issues in the field is reducing the initial cost of photovoltaic systems. Though solar energy is less expensive than other energy sources once a photovoltaic system is installed, the initial cost of installing the system or of building a solar power plant is currently very high. However, as more people use photovoltaics and the technology improves, prices are becoming lower.
Photovoltaics has also recently been concerned with improving the efficiency of solar panels. Since solar cells produce direct current (DC), which must be converted to alternating current (AC) for use in modern technologies, there is a loss of energy in the conversion process, currently from four to 12 percent. Experimental high-efficiency solar cells are not yet in wide use, but have achieved efficiencies of up to three times the current market average.