In order to use that electricity when the sun is not shining and/or the wind is not blowing, there must be some form of storage. This is where batteries come in. Options are wide. Lets take a look.
One of the most important decisions you are going to have to deal with in any off-grid energy project is figuring out the right battery system for your rig. Your battery bank is the foundation of your power setup. It’s something that you are going to have to deal with quite a bit because batteries come and go more than any other part.
What kind of batteries are people are using in the real world for off grid applications? Lets take a look.
Note: A normal car battery is designed to give a big punch to start a vehicle. Because of this, the plates inside these batteries are different from deep-cycle batteries. They CAN be used but are not recommended and will die quickly. There are deep-cycle batteries sold in this line, mostly for the RV market. They are usable.
Car batteries are not recommended for storage because of their not being deep-cycle batteries. RV variants of these Are deep-cycle.
|Golf Cart Batteries
6 volt golf cart batteries, are able to endure long periods of deep discharging and recharging with less effect on life span.
An L-16 battery is a category of vehicle batteries that uses renewable energy systems .
|Deep Cycle Marine Batteries
These lose capacity pretty quickly and can lose about half of their capacity in about 2 1/2 years. Not for recharging daily.
|Dedicated Battery Systems
A concise forklift battery guide can be found at Lift Truck Supply.
|Voltage||12 volts||6 volts||6 volts||12 volts||12, 24, 36, 48 volts|
|Life||Varies widely||4-5 years||5-8 years||2 1/2 years||Flat plate – 3yrs max
Tubular – 4-5 yrs
|Size-Weight||~8″ x 11″ x 12″
|~1′ x 1′ x 8″
|~1′ x 8″ x 17″
|~10″ x 8″ x 7″
|Cost||Free to about $200||$70-$200||$200-$600||$200-$400||Salvage to over $10,000|