12 volts, 24 volts, or 48 volts?
In many occasions the size of the system that you are making will dictate the voltage based on your component configuration. It's important to choose your voltage carefully since it can be difficult to change after your system has been built. Here is a quick guide to look over which will help you determine which Battery voltage is best for your system.
12 volt battery systems
Are common in smaller systems and standard in vehicles and RV’s Golf carts etc. If you’re putting a solar array on your Van, RV or Skoolie, odd’s are you’re going to be using 12V batteries.
- Simple and standard in most vehicles, RVs, and boats
- For small, simple power systems
Can be used directly in very small systems or add 120 volt AC with an inverter
24 volt battery systems
Are more common in larger systems like off grid cabins. You are able to run wires longer distances which is more common in off-grid cabins where you need have your array on a ground mount away from your cabin.
- Use with systems of more than 720 watts of solar modules
- Most power will be changed to 120 volt AC power. Voltage converters are available to run 12 volt DC equipment from 24 volt batteries
- Wires can run longer distances, use to accommodate:
- Solar modules over 75 feet from your home
- Wind generator or hydro turbines over 300 feet away
48 volt battery systems
Are common for larger and more powerful systems. Anytime you need wiring to run a long distance (up to 400 feet) 48 volt systems are necessary.
- Use with systems where wire runs of up to 400 feet are necessary to reach the only good solar location
- 48 volt inverters are more robust; and well suited for larger power systems
- Converters are available to get 12 volts DC from a 48 volt battery system
- MPPT type charge controllers can allow higher voltage solar arrays to transmit their power more efficiently and from longer distances. This allows for the array to be placed in the best location producing the most power possible. These controllers maximize the system’s output, saves wiring costs and properly charges the lower voltage battery system (12, 24 or 48V).