Although there are many individual ways in which solar cells can be used, there are still only 4 basic applications to use them. Essentially, any way a solar cell can be used will fall into a category that I shall briefly describe below.
Utility grid connections—This is when solar cells supplement energy needs for the house or commercial business, being hooked into the regular electrical grid and supplying power directly through the lines. If more electricity is generated by solar than is needed, many electrical companies will give credit and/or refunds for the extra power sent back into the lines.
A Grid interactive System—When solar cells are used to maintain and charge up battery back-up systems for household or commercial usage. Any person or business would use a system like this to insure continued power if main grid electricity was shut down for any reason. Computer banks might benefit greatly from this technology.
Remote solar cell usage—Solar cells and panels used as an electricity supply in places where electrical service has not been developed yet. Wilderness cabins, undeveloped landscape and 3rd world countries would all benefit with using solar power in these remote areas.
Product applications for Consumers—Basically the use of solar cells to replace battery applications in a wealth of products. Things like calculators, cap fans, and any low voltage toy can be made to run off of solar cells saving on battery use and consequently, landfill issues for discarded batteries.
With the newer higher efficiency solar cells and panels on the market today, these applications have become more common and useful than ever before.