There is a common but wrong idea that solar panels are only effective in places with a lot of sunshine. The reality is that home solar panels are being used successfully in less sunny regions like the US Northeast and Pacific Northwest.
You can also find examples in other parts of the world: Netherlands and other nations have more than 600 watts of solar capacity per person, according to a recent report by SolarPower Europe (PDF). Those nations have relatively low sunshine.
Sunlight made into electricity. It’s that simple. Enough electricity to power not just a few appliances, but an entire home, including transportation in case of battery electric vehicles (BEV) or plug-in hybrids. That’s where we are quickly heading, but let’s deal with the basics of solar power for homes, first.
PV stands for Photovoltaic. — The quantifiable process of converting sunlight (solar) into electrical power. For the conversion to be realized and useful, the right semiconducting material must be in place. — This results in efficiency that helps us put into perspective how solar energy can and does compare to historical methods of producing electrical power.
Solar cells are the fundamental, man-made part. Each cell produces about 1 to 2 watts of power. While that isn’t much, for the small size they are, it’s actually quite sufficient.
Group cells together into modules and stack modules into arrays, and suddenly kilowatts of electric power can be realized. To visualize what we are communicating, check out this short video from the U.S. Department of Energy.
For the solar cell to be effective and efficient, it must be properly housed and protected. Durable glass for its transparency is the obvious choice and results in the modules we call PV solar panels.
A module can be as small as those found on calculators, which date back to mid-20th century technology. Or modules can be arranged as solar arrays, which today is what we consider to be a solar panel system.
Contemporary solar cells are manufactured in about a half dozen ways. The ongoing and still most popular material is crystalline silicon. – Its relatively high efficiency in converting energy supplied by photons to electrical power is why it continues to be popular.
Monocrystalline vs. Polycrystalline Solar Panels
There are two main types of solar panels on the market today: monocrystalline and polycrystalline.
Monocrystalline panels provide anywhere from 17% to 22% solar energy-to-electricity conversion efficiency, while polycrystalline panels achieve between 13% and 16% conversion efficiency.
Thanks to their higher energy conversion efficiency, monocrystalline panels are more costly on a per watt basis than polycrystalline panels, but they do occupy less space on the rooftop.