Searching on line for solar panels for sale, or calling solar stores and solar contractors in your area is a good move but it is not recommended as a first step. My advice is to acquire some basic knowledge about solar power for homes systems first. In this page you’ll find basic tips on solar panels buying, the very basic solar panels buyers guide
Solar panels for sale differ; you may find different technologies, different manufacturers and vendors, different warranties, different output voltage and different electrical power production capability. Nevertheless, there are common features that are common to all solar panels.
Solar panels convert directly sun radiation into electrical power using the photovoltaic effect. Solar panels must be exposed to the sun in an optimal way. The optimum is achieved when the solar panel plane is perpendicular to the Sun. Most solar panels are mounted facing South and tilted with an angle to the horizon. Therefore, as the Sun moves the solar electric panel is not exactly perpendicular to the Sun but this installation practice is considered as a practical engineering compromise.
Solar panels generate Direct Current (DC) electrical power. Since most home appliances use standard AC power, a DC to AC solar pure sine wave inverter is a solar component that must accompany the solar panel.
The electrical power production capability of every solar panel will degrade during the years they are in active service (exposed to the sun; no degradation is expected while the panel was in storage)
The following are the solar panels buying tips :
Life span expectancy influences the life cycle cost. The cheapest buying price is not always the best buy. "Cheap" panel that will last only 5 or 7 years is more expensive than an "expensive" high quality panel that will last 20 years.
Comparing prices, look into the price in $ per watt electrical power capability. Don’t rule out lower efficiency panels, lower efficiency translates into larger area; typical roofs can provide the needed area. Just to get the feeling, to generate 2,000 Watts you need 200 square feet roof area if you buy 12% efficiency panels or 160 square feet if you buy 16% efficiency panels.
If you can afford the capital investment buy the capacity you plan for in one fell swoop. You will get better volume prices in $/watt for bigger orders. Theoretically you can take a modular approach by building the solar system gradually. However, you may not find 2 years from now the same models that are presently on the market and the government will terminate the energy tax credit allowance in the future (year tax 2016). I stumbled upon a site, 1bog.org that help to form buyers groups for buying solar systems collectively at reduced prices. Search "group buying solar systems" for alternative sites.
Buy from manufacturers that are well recognized and that have a good reputation, and look into the warranty terms.
Buy the capacity with the smallest number of panels, for example buy 16 panels, each 130 Watts and not 33 panels each 60 watts; don’t go after bigger than 130 watts panels, 130 watt panels are not too bulky and not too heavy.
Watch for seasonal solar panels for sale campaigns
How to get the maximum out of installed solar panels?
After you have bought your residential solar power system, how can you get the most out of it? Here are few tips:
Keep the panels clean; dust blocks the Sun rays.
Shading reduce the solar panel output, and partial shading might "confuse" the MPPT DC to AC solar inverter. Avoid shades on your solar panels, trim the trees that shade your panels if necessary.
The solar panels output is reduced when the temperature rises. Allow for air flow around the panels so heat can be removed, do not pack the panels tightly together.