Photovoltaic cells are made of special materials called semiconductors such as silicon, which is currently used most commonly. Basically, when light strikes the cell, a certain portion of it is absorbed within the semiconductor material. This means that the energy of the absorbed light is transferred to the semiconductor. The energy knocks electrons loose, allowing them to flow freely.

Sunlight is Earth's primary source of energy.

The energy stored in petroleum and other fossil fuels was originally converted from sunlight by photosynthesis in the distant past.[119]

What are photovoltaics? The word comes from “photo” (light) and “voltaic” (energy produced by a chemical reaction). Photovoltaic technology refers to the conversion of light into energy at the atomic level. Certain materials, such as silicon, cadmium, and selenium, have the ability to absorb light photons and release electrons. Solar photovoltaic technology harnesses these freed electrons and uses their electric current as DC electricity (NASA 2002). Fully powered by the sun, solar photovoltaics are a free, clean, and renewable source of energy that can be used independently of or in conjunction with conventional grid energy. Unlike solar thermal systems, solar energy panels require little maintenance, necessitate no moving parts, and last for 30-40 years.

First used in about 1890, "photovoltaic" has two parts: photo, derived from the Greek word for light, and volt, relating to electricity pioneer Alessandro Volta. And this is what photovoltaic materials and devices do—they convert light energy into electrical energy, as French physicist Edmond Becquerel discovered as early as 1839.

The Brazilian government still awaits a reduction in solar prices to create a specific auction by the end of 2013 or the beginning of 2014. However, the Ministry of Mines and Energy (MME) does not demonstrate any signs of this happening.

In 2013, however, revenue and capacity installed are expected to double: projects will be delivered, the resolution 482/2012 will have a major impact, and X% of the National Association of Electric Energy’s (ANEEL’s) research and development (R&D) will conclude. Capacity installed expectations in 2013 will near X megawatts (MW); in 2014, X MW; in 2015, X MW; and beyond, faster expansion is expected. Currently, capacity installed for the solar market is X MW, but it is expected to reach X MW by 2017. The total possible capacity installed for Brazil is close to X gigawatts (GW). This market revenue will have a X% compound annual growth rate (CAGR) during the forecast period (2012–2017) due to ANEEL´s R&D, international events, and the resolution 482/2012 cost reductions. Now, market revenue is close to $X million and can reach $X million by 2017.

Distributed generation could grow faster with financial support, better service from energy concessionaries, and cost reductions; nonetheless, it will grow considerably.

Over 19,000 MW of non-residential PV project applications have been approved under its FiT scheme as of the end of May.

Over 19,000 MW of non-residential PV project applications have been approved under its FiT scheme as of the end of May.

With a 2013 forecast of 8.5 GW and 7 GW respectively, China and Japan are on pace to be the top installers this year. PV installations in the United States continue to grow and are forecasted to reach approximately 4.5 GW in 2013. Other major markets forecasted in 2013 are Germany at 4 GW, Italy at 2 GW, UK at 1.5 GW and India at 1 GW.