Remote or mobile power and energy independence.

What is off grid solar?

What are some typical applications of off grid solar power?

How much more expensive is an off grid solar system for my home than a grid tie system?

What is off grid solar?

An off grid solar power system consists of a bank of batteries, a battery charge controller, a solar panel array, and a power inverter if AC electricity is needed for the application.

Off grid power can be used in mobile applications such as on RVs, boats, or other vehicles as well as in remote power applications where the nearest utility line or breaker panel is distant. Depending on the application, it may be less expensive to power a building or device with solar than it would be to run a power line to the location. This depends on the amount and type (AC or DC voltage) of power needed at the install site. When compared to diesel or propane remote power systems, a solar off grid system is far more maintenance free and reliable.

What are some typical applications of off grid solar power?

A solar panel can be mounted on a boat or RV to maintain a battery bank's charge and reduce or eliminate the need for a plug-in charger and a AC power source.

Gate openers, water wells and pumps, tool sheds, outdoor lighting, and remote cabins are common off grid solar applications.

My electric utility won't do net metering / my net metering agreement is lousy / I want to be energy independent...
How much more expensive is an off grid solar system for my home than a grid tie system?

There are several factors which can make an off grid system for a residence more expensive. The first is the large bank of batteries needed and the charging system for them. There is the upfront cost for this, and the ongoing cost of replacement every 3-10 years depending on the quality of battery used. Another factor that affects the price is the fact that an off grid system must be sized for the maximum usage of electricity anticipated rather than just the average power usage over a year. This affects both the size and cost of the solar array required and also the size and cost of the power inverter. This can result in a system that might end up costing 50-80% more than a comparable grid-tie system, which are already not cheap.

One idea to eliminate some of this extra cost, is to use an off-grid system to power the base-load of your home (generally your lowest monthly utility bill). The base load in most cases is everything except for your heating and cooling, which flutates throughout the year (and usually makes up at least half of your total electric power usage). That way the system size needed would be approximately cut in half, and the design wouldn't have to handle the massive air conditioning power requirements in the middle of the summer.

But a small off grid system can also be an inexpensive way to learn about solar in a hand's on manner. For example, you could build a system just large enough to power your computer and other items in a home office or bedroom and then gradually add to it over time.

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