By best I mean safest places. If I were to install them on my roof am I risking due to damage from weathering? Such as rain or snow. I don't get very high winds around here, nor any natural disasters such as hurricanes or tornadoes. Does anyone have solar panels that have been durable for a long time? Is it worth the investment?
Probably not worth it. Sure, it is a great idea, but it will take decades to get your money back in energy savings. Today's panels are fine for a roof. However, I'd worry a little about the interface (where leaks could occur) especially in a retrofit. They, of course, will need to face south.
Solar panels have to be installed so that they face the equator, so they would have to point south in the U.S.. There are panels designed for exterior mounting and panels designed to go behind glass walls, I've even seen some that are made to replace roof shingles. You'll have to determine if they are worth it or not. Most companies that manufacture the panels rate the output based on the area in which you live. If you live in the north, payback is usually over 20 years, closer to the equator the payoff is quicker, but still a while. The question of worth is relative: are you trying to save money or help save the world? Any alternative to hydro carbon is great for the environment, but most are still very expensive.
Photovoltaic panels are designed to be put on a roof, exposed (obviously) to sun, but also rain, snow, and wind. Generally, there is even a rating for something like hail. A good mounting system will be stronger than the underlying roof, so will withstand most anything short of a direct hit by a tornado or hurricane. There are a few panels from the 70's (that's the 970's) still in operation, I believe. They look horrible, but are still producing a little electricity. Since then, housings have improved, and panels generally have a 25-year warranty today (some cheap ones are 20-year warranty).
The best place is where they get the most sunshine. Naturally they will be exposed to rain and snow.
