We assume the following:
Using 12V system.
Coolzy-Pro operation hours: 7 hours
Inverter efficiency: 85% (Good quality modified sine wave inverter)
Depth of discharge: 95% (Lithium deep-cycle battery)
Constant power demand = 340W.
With a 12V battery, the current will be 340 / 12V = 29 Amp (Make sure the battery cables you use can carry 30 Amps constant current).
Transient peak power demand is about 1800W for 5-15 milliseconds.
1800 / 12V = 150 Amp ( Make sure your battery has a CCA rating equal or higher than 150 Amp)
The battery size can be roughly estimated with the following equation:
(duration x steady battery current) / (depth of discharge * inverter efficiency)
Based on the above figures, the equation gives:
(7 hours x 29 Amp ) / ( 0.95 depth discharge x 0.85 inverter efficiency ) = 250 Amp-hours
This is the smallest battery size it requires to run the AC for 7 hours. Please note that the Coolzy when used with the Igloo tent has the potential to extend the operation time by about 30% under certain and remote control settings. Further, if the return air temperature drops below the thermostat temperature setting, the compressor will stop for a couple of minutes, reducing the average power consumption.
Please also allow sufficient extra capacity for other appliances that could possibly consuming power at the same time. If you are uncertain about the steady current being supplied by the battery, install a current shunt as explained in the next section.