With the constant breakthroughs in key technologies, optoelectronics will become a viable source of energy, while the price is also very competitive compared to traditional energy sources. The importance of renewable energy sources has become increasingly prominent, which stems from people want to reduce carbon dioxide emissions as well as strong dependence on fossil energy urgent needs.Photovoltaic technology contains a huge environmental benefits and political interests. Optical is the only way to meet the long-term global energy demand and do not emit greenhouse gases energy technologies. 

This part of the Earth's surface to reach the sun to provide energy equivalent to the current global energy demand 10,000 times. Moreover, we can use solar energy almost everywhere. On average, the earth exposed to sunlight every year, every square meter area can receive 1700kWh energy. According to the European Energy Research Center predicted that by 2050, pure sine wave inverter energy will provide a total human demand 20% to 30%. 
    
   However, PV (Photovdtaics, PV) technology, the cost is still higher than the cost of traditional energy grid, and take up a lot of space to generate electricity.Although the energy from the sun is very rich, but very scattered, the use of solar power requires a large area silicon photovoltaic panels. The sun's energy is free, but its energy is converted into electrical energy is not free. Development and utilization of solar energy cost is still the biggest problem. 

Compared to the residential electricity prices, the average cost of solar power 2 to 5 times higher. However, with the constant breakthroughs in key technologies, the cost of solar power has also been reduced. mppt charge controller module prices from 1982's $ 27 per watt peak power is reduced to $ 4 per watt today. In addition, many countries introduced a feed-in tariff (one kind of government commitment to purchase PV electricity at a predetermined price subsidies), the global solar capacity in the past five years at an annual rate of more than 50% of rapid growth, and is expected to continue its rapid growth. 
    
   Attract high economic returns, more and more companies are involved in the photovoltaic (PV) market. Global photovoltaic industry in the new technological aspects of power generation equipment and is investing heavily. The rapid development of a photovoltaic field visible signs appeared in 2006, this year, the global polysilicon production over the first half instead of being used in the field of optoelectronic semiconductor IC production. 

It also includes a number of semiconductor manufacturers. For example, the semiconductor equipment supplier Applied Materials set up a new Solar Group SunFab, developed specifically for the production of solar cells and thin film photovoltaic module manufacturing tools needed. Furthermore, Cypress Semiconductor founded a subsidiary engaged in solar energy development SunPower; National Semiconductor also began to get involved in the solar market, recently released several solar panels that enhance the efficiency of the chip.