Let’s throw the drama out and let the cold, hard facts do the talking.
Why would I need a battery?
With the correct solar array and a large enough battery, it’s possible to run your home on solar energy alone. Also, depending on the time of day and your electricity tariffs, using stored battery electricity may be cheaper per kilowatt-hour than using grid electricity.
Double dipping can be a good thing after all.
What to look for in a solar battery
Capacity – how much energy (usually measured in kWh) the battery can store.
Depth of discharge (DoD) – the percentage of energy that can be safely used without speeding up battery deterioration. Most battery types need to hold some charge to avoid damage.
- Lithium batteries can be discharged to about 80–90% capacity
- Lead-acid batteries to about 50–60%
- Flow batteries can be fully discharged.
Power – How much power (in kilowatts) the battery can supply.
Efficiency – how much the battery will store and put out again. There’s always some loss.
Cycle life – how many charge/discharge cycles does the battery have before it’s deemed to reach the end of its life.
Lifespan – the expected life of the battery (and warranty) can be measured in cycles or years.
Ambient temperature range – batteries are sensitive to temperature and can degrade or shut down in very hot or cold environments.
Location – most battery systems like to be inside and protected from the elements. However, some batteries may be installed on an external Southern wall.
