So why isn't solar electricity more common? It's largely a question of cost efficiency right now. Though the photovoltaic (PV) effect---the phenomenon that certain materials when struck by photons (light from the sun) emit electrons, the basic building block of electricity---was discovered in 1839, comparatively little research has been done over the years. Because fossil fuels have continued to be available and relatively inexpensive, alternative energy research has never become a high priority. Even without consistent government funding, however, the technology has been moving forward, though slowly.
The Arab oil embargo briefly focused attention on sources of alternative energy back in 1973. Then the Gulf War of 1980 got folks thinking again about where our energy comes from and how dependent we are on oil from afar. This summer's gas prices will likely do the same again.
Meanwhile, in much of northern Europe and in Japan, population densities are much greater than here in the U.S., making new fossil fuel-burning power plants far less popular an option (who wants smokestacks in their backyard?!). As a result, the adoption of wind and solar technologies in these countries continues to outpace the U.S.
And in developing countries, with their limited resources and (very often) huge land areas, locally produced photovoltaic electricity promises to be competitive with, if not actually cheaper than, building conventional power plants and transmission lines.
Demand---and Use---is Growing in the U.S., Too
Overall, prospects for the future are bright, not least of all due to recent advances in the technology of producing the basic building blocks of PV electricity---the PV cell. These cells, primarily made of crystallized pure silicon, the second most abundant element on earth, have been coming down in price about 15% a year since the mid 1980s while their efficiency has been increasing the whole time. As a result, more people have been "hooking up to the sun," which has in turn brought costs down further, because production costs diminish as manufacturing volume increases.
Also, because PV electricity is clean (non-polluting), reliable (there are no moving parts in the cells or the modules and arrays created by wiring many cells together), and durable (cells typically last 20-40 years, depending on conditions), it only stands to gain in popularity in the years ahead.
It's Cost Efficient in Certain Applications Already
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Already, here in the States, many folks in more remote areas have found PV electricity the most cost-efficient means of providing power for their homes (or vacation homes or cabins). Boat and recreational-vehicle batteries are often charged using solar trickle chargers. Electric fences, farm or ranch lighting, wells, gate openers, and other agricultural devices also are ideally suited to using PV electricity.
And even in the suburbs, landscape lighting is often solar powered these days, not because it's less expensive necessarily, but because the installation is as simple as placing the light where it will receive sunlight---no wiring required. As convenience increases and the cost of fossil fuels continues to rise, more and more common electrical appliances are likely to become available in solar-powered versions.