Loading the page...
Preparing tools and content for you. This usually takes a second.
Preparing tools and content for you. This usually takes a second.
Fetching calculator categories and tools for this section.
Estimate a minimum rated battery size in watt-hours and kilowatt-hours for portable power stations (“solar generators”) from your daily energy budget, how many days you want stored before recharge, and how aggressively you use the pack’s rated capacity.
Last updated: April 17, 2026
Need a custom energy or outdoor calculator? Get a Quote
Add up device Wh: (watts × hours) for each load you run per day.
Days of use without sun (1 = nightly top-up).
Share of rated capacity you actually draw (BMS reserve, cycle life).
Rough inverter sizing hint (+20% headroom) when provided.
Min rated (Wh)
2,500 Wh
Same energy (kWh)
2.50 kWh
Equivalent Ah @ 12 V
208.3 Ah
Equivalent Ah @ 24 V
104.2 Ah
Safety & accuracy:
Loads
Σ (watts × hours)
Storage days
daily × days
Headroom
÷ (usable %)
2,000 Wh/day, 1 storage day, 80% usable fraction — minimum rated pack about:
2,500 Wh
(2.50 kWh)
First the tool multiplies your daily watt-hour budget by the number of storage days to get total stored energy required before accounting for how much of the manufacturer’s rated capacity you are willing to use. Dividing by the usable fraction converts that into a minimum nameplate watt-hour rating. Amp-hour equivalents divide watt-hours by 12 or 24 volts for quick comparisons with legacy lead-acid style thinking. If you enter a peak simultaneous AC load, it suggests a continuous inverter rating with a small headroom factor.
storageWh = dailyWh × storageDaysminRatedWh = storageWh / (usableFractionPercent / 100)104.2 Ah
Compare listings that advertise 12 V or 24 V nominal packs alongside Wh ratings.
Share it with campers and homeowners comparing portable power stations.
Suggested hashtags: #SolarGenerator #OffGrid #Camping #Battery #Calculator