PV Gap

Luis Said:

How many solar panels could £3 million get me,and how many homes would that power?

We Answered:

For the price on solar panels and their output, consider:

http://www.ebay.com

Next, consider the outputs to be maximum for when the sun is shining directly on them. What you will actually get depends on where you are, and how often it is cloudy. Also, it depends on whether you install the panels statically, or on a surfaces that automatically move to tract the sun. The actual capture of radiation is theoretically:

Actual Power = (Solar Power)sin(angle between the Panel and the rays)

Usually, it will be better than the equation above since the Maximum power will not capture every photon anyway as the Panel becomes saturated. But do not expect the power to be much better. If your Panel is pointing at noon time sun for the day, expect it to get only half the power of a Panel that actively tracks the sun. Since noon sun is different every day, expect your Panel to do even less if its angle is not adjusted every day. If you do not do this, you will loose another 8% over time.

For a totally static Panel, the best angle is to orient your panel so that it points straight upward, then adjust it downward in the due South direction (or due North if you are in the Southern Hemisphere) the number of degrees indicated by the geological latitude. If for some economic reason, you wish to choose a different orientation, the resultant efficiency will be:

Efficiency = cos(angle from optimum)

How much electricity a home uses depends on where it is located, and the habits of the inhabitants. In the USA, a typical home requires about 24 KWH per day. If you are planning to use solar power to run these homes, you will either need to have some auxillary power source to power them when the sun is not shining, or some method like batteries to store the electric power. At least some buffering of power will be needed to manage variable power demands. Cost all of that out as well. Also, remember that the power you will get will be low voltage DC. The conversion to AC will require some expensive equipment as well. Expect to lose 15% of your power in conversion and transmission (assuming that the distance is not great).