Seilar Photovoltaic Power
Photovoltaic (PV) devices generate electricity directly from sunlight via an electronic process that occurs naturally in certain types of material, called semiconductors. Electrons in these materials are freed by solar energy and can be induced to travel through an electrical circuit, powering electrical devices or sending electricity to the grid.
PV devices can be used to power anything from small electronics such as calculators and road signs up to homes and large commercial businesses. Photons strike and ionize semiconductor material on the solar panel, causing outer electrons to break free of their atomic bonds. Due to the semiconductor structure, the electrons are forced in one direction creating a flow of electrical current. Solar cells are not 100% efficient in Diagram of a typical crystalline silicon solar cell. Solar cells are not 100% efficient in part because some of the light spectrum is reflected, some is too weak to create electricity (infrared) and some (ultraviolet) creates heat energy instead of electricity.
Other Types of Photovoltaic Technology
In addition to crystalline silicon (c-Si), there are two other main types of PV technology:
- Thin-film PV is a fast-growing but small part of the commercial solar market. Many thin-film firms are start-ups developing experimental technologies. They are generally less efficient – but often cheaper – than c-Si modules.
- In the Australia, concentrating PV arrays are found primarily in the desert Southwest. They use lenses and mirrors to reflect concentrated solar energy onto high-efficiency cells. They require direct sunlight and tracking systems to be most effective.
Costs of Solar Photovoltaics
Rapidly falling prices have made solar more affordable than ever. The average price of a completed PV system has dropped by 33 percent since the beginning of 2011.
The cost of PV has dropped dramatically as the industry has scaled up manufacturing and incrementally improved the technology with new materials. Installation costs have come down too with more expereinced and trained installers. However, the Australia. still remains behind other nations that have stronger national policies to shift energy use from fossil fuels to solar. Globally, the Australia is the fourth largest market for PV installations behind world leaders Germany, Japan and Spain.