Off-Grid Systems
Off-Grid Systems will provide all the power you use and store energy in batteries, with no connection to the utility. Ideal for cabins, remote sites, or for those who just do not want to rely on the utility to provide their power. A home solar system typically consists of solar panels, a back-up battery, a charge controller, wiring and support structure. (The photos below illustrate a variety of applications.)
Stand-Alone Systems
Stand-alone PV systems are often best in places where utility-generated power is either unavailable, undesirable, or too costly to hook up to. Stand-alone systems are also excellent for uses that don't require a lot of power. The most simple PV systems are those that generate direct-current (dc) electricity so it can be used right away to run water pumps, fans, and many other appliances that use dc electricity. They produce energy where and when it's needed, so complex wiring, storage, and control systems aren't needed, and small systems are easier to transport and install.
PV with Batteries
PV systems with battery storage are used all over the world to provide electricity for lights, sensors, recording equipment, switches, appliances, telephones, televisions, and even power tools. These can be designed to power equipment that requires dc or ac electricity by adding an inverter. We operate PV/battery systems by connecting the photovoltaic modules to a battery, and the battery in turn to the load. During the day, the PV modules charge the battery, and then the battery supplies power to the load as needed. A charge controller keeps the batteries charged properly and helps prolong their life by protecting them from overcharging or from being completely drained. The amount of electricity that can be used after sunset or on cloudy days is determined by the output of the PV modules and the nature of the battery bank. Including more modules and batteries increases system costs, so energy usage needs to be studied carefully to determine the best system size for the load. And batteries designed for PV projects pose the same risks and demand the same caution in handling and storage as automotive batteries.
PV with Generators
When remote or non-grid-connected power is needed and must be available, or when users know they'll occasionally need a larger amount of power than a PV system can supply alone, PV is still a practical choice. We just need to add an electric generator that can work effectively with a PV system to supply the load. During the day, the PV modules quietly supply daytime energy needs and charge batteries. If the batteries run low, the engine generator runs at full power - its most cost-and fuel-efficient mode of operation - until the batteries are charged. In some systems, the generator makes up the difference when electrical demand exceeds the combined output of the PV modules and the batteries. Having an engine generator as a backup means fewer PV modules and batteries will be necessary to supply power whenever it's needed. Including a generator makes designing a PV system more complex, but modern electronic controllers allow these kinds of systems to operate automatically.
With integrity and expertise, you can count on Home Energy to advise you in finding the system best suited for your conditions.
Featured Off-Grid Installations
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COMMERCIAL INSTALLATION
UNL Furs
2.5 kW Off-Grid Solar and Wind System
Etna Green, Indiana
September 2008 -
RESIDENTIAL INSTALLATION
260 Watt Off-Grid Solar Water-Pumping System
LaGrange, Indiana
August 2008 -
EDUCATIONAL INSTALLATION
Ball State University
1kW Solar PV, Solar Thermal & Bergey Wind
Muncie, Indiana
June 2008 
RESIDENTIAL INSTALLATION
Off-Grid Solar System
Etna Green, Indiana
October 2007
