Photovoltaics

Photovoltaics is a high-technology approach to converting sunlight directly into electrical energy. The electricity is direct current and can be used that way, converted to alternating current or stored for later use.

ARCO photovoltaic plant, Carrizo Plain, near California Valley, CA

Conceptually, in its simplest form a photovoltaic device is a solar-powered battery whose only consumable is the light that fuels it. There are no moving parts; operation is environmentally benign; and if the device is correctly encapsulated against the environment, there is nothing to wear out. Because sunlight is universally available, photovoltaic devices have many additional benefits that make them usable and acceptable to all inhabitants of our planet. Photovoltaic systems are modular, and so their electrical power output can be engineered for virtually any application, from low-powered consumer uses-wristwatches, calculators and small battery chargers-to energy-significant requirements such as generating power at electric utility central stations. Moreover, incremental power additions are easily accommodated in photovoltaic systems, unlike more conventional approaches such as fossil or nuclear fuel, which require multi-megawatt plants to be economically feasible.

The demonstration of higher performance, lower cost and better reliability in today's photovoltaic systems is leading many different end users to assess the value of these systems for their particular applications. Aggregation of these applications will lead industry to commit to larger, more cost-effective production facilities, leading to yet lower costs. Public demand for environmentally benign sources of electrical energy will hasten adoption of photovoltaics. How quickly these adoptions occur will be dictated by the economic viability of photovoltaics with respect to the competing options. It is no longer a question of if, but when and in what quantity, photovoltaic systems will gain adoption. Clearly the energy system of the future has become today's consideration.

More Information

Sandia's photovoltaic systems project: Seeking to ensure photovoltaic systems
perform to their potential.

Photovoltaics Special Research Centre: Dr. Stuart R. Wenham, co-author of the book "Applied Photovoltaics" and author of more than 80 journal and refereed conference publications. He has been awarded more than 20 patents for solar cell work.