We added this as a separate post because a few people asked about this after we posted about the ‘Can I power a 12V fridge off a leisure battery?‘ article we wrote.
So, how long does a leisure battery last?
It is most simply explained with the following formulas:
First, find the Total Energy(Wh) of the battery:
- Battery Capacity (Ah) * Battery Voltage(V) = Total Energy (Wh)
You can then work out the hours of use:
- Total Energy(Wh) / Fridge Power Consumption (W) = Hours of Use
Explained:
Battery Capacity (Ah) is the amp-hour. This is the amount of charge that the battery can deliver over a certain period of time.
Battery Voltage (V) is the voltage rating. This is the amount of electrical potential that the battery has.
Total Energy (Wh) is the total amount of energy, which is the product of the battery capacity and voltage shown above.
Fridge Power Consumption (W) is the amount of power that the fridge consumes in watts.
Hours of Use is the total amount of time that the fridge can run on the battery before the battery is drained.
Example: if you have a 1000 Ah leisure battery with a voltage rating of 12 V, the total energy that the battery can deliver is 12000 Wh (1000 Ah * 12 V). If your fridge consumes 50 W of power, then the battery can power the fridge for approximately 240 hours (12000 Wh / 50 W = 240 hours).