A stand-alone power system to provide all of the power for a remote home or ranch. Systems of this type are often found in areas where power company lines are costly to bring in. The cost of the system can be substantially less than the cost charged by the power company just to bring power to your home. Once the initial cost of a renewable energy system has been made there are no monthly utility bills and no overhead power lines and poles to disrupt the view shed. Stand-alone systems are found in the mountain and desert areas and many in Baja California.

Backup power systems provide power when grid power is lost due to overload, fire, flood or other calamities. Often times these systems are merely backup generators. But generators are noisy, dirty and loud and increasingly stringent government restrictions regarding noise levels and other environmental concerns restrict their use. In San Diego County the building inspectors require the generator to meet UL standard 2200. The selection of small home sized generators meeting this standard is limited. However for hospitals, fire and police stations and other emergency and necessary services backup generators are an absolute necessity.

Grid-tie systems, also called net-metering systems connect the renewable energy source, (solar panels or wind generator) to the electric meter at the power entrance. As power is generated by the renewable source it is either used or fed back through the meter causing the meter to run backwards. Thus a credit is built up as the meter runs in reverse and the utility customer draws against that credit when he uses more power than he currently is producing. A solar system will produce power during daylight hours but none after the sun goes down. A common misconception is that these types of systems protect against power losses. Not so, a power loss will also shut down the equipment that feeds power back through the grid. This is because power company service personnel will probably be working to restore power. For their protection power lines need to free of back feed from other energy sources.

Grid-tie with backup systems combine backup battery systems (or in some cases a backup generator) with a renewable energy source that operates like a grid-tie system until there is a power loss and then the battery bank and renewable source kick in and provide power.