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The amount of energy that falls to the Earth's surface in a single minute is enough to meet the world's energy demands for an entire year. |
The amount of energy that falls to the Earth's surface in a single minute is enough to meet the world's energy demands for an entire year.
Humans have had the ability to produce electricity from sunlight since 1839, when a French scientist discovered that light falling on certain materials could create an electric charge.
The concept of solar power didn't catch on until the 1960's, when the U. S. space program began to use silicon-based photovoltaic cells to power their satellites.
Since then, solar power technology has gradually become more efficient and widespread. It has recently gained prominence in many areas as the full effects of burning fossil fuels for electricity are being realized. Global climate change, acid rain, and smog are among some of the key environmental problems that solar energy could help solve.
Today's solar technology includes low-tech solutions like building designs that can utilize the heat of the day for heat in the winter, and are shaded from the sun in the summer, as well as other types of passive solar heating technologies. Passive solar technologies can also be implemented into a building desing in order to utilize solar cooling and lighting. More high-tech solutions use the sun's rays for direct solar-electric conversion. Included in this category are solar electric (photovoltaic), solar thermal, and solar heating and cooling technologies.
Implementing passive technologies in building designs is much more cost effective, both immediately and in the long term, than trying to retrofit a building for solar energy after it is built. Because solar power technology is not produced at a very large scale, its cost is often inhibitive, it takes a combination of inherent energy conservation and long-term thinking to make it feasible in most cases.
The following is a block diagram of a Photovoltaic (PV) system:
A system such as this can be used independent of an established utility electric grid, which is good for remote locations. However, in cities and areas with established grids, it is possible to tie the PV system directly into the grid. With this, energy can be used by the owner when needed, but will be fed directly back into the grid for a credit when production is greater than consumption.