Load Calculator
Search a library of 140 household loads with typical watts already filled in, add the things you need to keep running during an outage, set how much of the day each one is on, and how much of the hour it is actually on, and the calculator shows your average draw, your daily watt hours, and how many nights a 2,048 Wh power station lasts if you only plan on 90 percent of the label.
The short version
- Default night is a closed fridge at about 150 watts, on about a third of the hour. Optional rows for a router at about 10 watts, a CPAP at about 50 watts, and lamps. Average watts times 24 is watt hours per day. Nights are that daily spend against 2,048 watt hours at 90 percent usable. A 1,500 watt heater is an evening, not a weekend. Arithmetic, not a hold. Searchable library of typical household loads. Jackery, BLUETTI and Anker SOLIX C2000 Gen 2 prices checked October 12, 2026.
The longer fridge essay is how long a solar generator runs a refrigerator. The night itself, cords and all, is what a station really runs. This page is the adding machine.
How to use
- 1Find your appliances. Type in the search box, like fridge, modem or well pump, or tap a category such as Kitchen or Medical. Tap any result to add it to your list as a card. Every item comes with typical watts filled in, so you do not have to look them up.
- 2Check the watts. Running watts is what the appliance pulls while it is working. Our numbers are typical estimates. If the label or manual on your own appliance shows a wattage, type that in instead.
- 3Set the duty. Duty is the share of the whole day the appliance is actually drawing power. A fridge compressor cycles, so about 33 percent. A router is on all the time, so 100 percent. A microwave used for 15 minutes a day is about 1 percent. Drag the slider or type a number.
- 4Switch cards on or off. Use the switch on each card to try your list with and without a load. Tap Remove to drop it, Add a custom load for anything not in the library, or Reset to go back to the starting list.
- 5Read the results. The dark panel shows your average watts, the watt hours you use per day, and how many days your battery covers. Type your own battery size and output if yours is different. The colored bar shows which loads eat the most of a day, and the second bar shows whether everything switched on at once fits the station’s output.
The calculator
3Your results
About these numbers.
The battery starts at 2,048 Wh, the BLUETTI AC200L and Anker SOLIX C2000 Gen 2 nameplate, and 2,400 W is the continuous output both print. Change both to match your own station. Usable here is 90 percent of the label, because LiFePO4 likes a margin and inverters skim a little. A day, for this page, is 24 hours.
What those three numbers are
Average watts. Running watts times duty. The fridge at 150 watts and 33 percent is about 50 watts. That is porch light money. A router at 10 watts, always on, adds 10. A CPAP at 50 watts, left at 100 percent, adds 50; if it only runs the night, drop the duty toward a third. Lamps at 10 watts and 25 percent are a couple of evening LEDs, not a chandelier.
Watt hours per day. Average watts times 24. The default fridge is 1,188 Wh. That is the spend. Open the door and you are not in this model anymore; the compressor stays on longer, and tomorrow’s hours move into tonight. The fridge runtime page tells that story with the door kept closed.
Nights on the tank. 2,048 Wh times 0.90, then divide by the daily spend. The 90 percent is the conservative cut this site already tells people to take: do not plan on the last drop of the label. Default fridge lands around a night and a half. The rounded “about two days” on the fridge page is the same arithmetic without that haircut, on a door that stays shut. Both can be true. Plan with this one.
The 1,500 watt problem
Resistance heat does not care that you also wanted the milk cold. 1,500 watts into a 2 kWh tank is an evening with a warm corner, then a dark one. Add a load, type 1,500, and the nights line will say so in hours. Wear the sweater. If heat is the job, this class was never the machine: standby generators or a home battery that can actually carry it.
The tank this math is for
Full product notes already exist. This is only the adding machine, pointed at the same three ~2 kWh 120 volt stations. Our pick on this page, for the fridge and CPAP night, is the BLUETTI AC200L.
$899 at BLUETTI, opens in a new tab
Price checked Oct 15, 2026
- BLUETTI AC200L: 2,048 Wh, 2,400 W, 62.4 lb, $899 and orderable at bluettipower.com/products/ac200l, with delivery in 2 to 5 business days, checked October 12, 2026; extra batteries printed to 8,192 Wh, still 120 volts. Our pick because the fridge night is its job, and the attic is there if the outage teaches you to want more hours. See BLUETTI AC200L on bluettipower.com.
- Anker SOLIX C2000 Gen 2: same 2,048 Wh tank, 2,400 W continuous, 4,000 W peak printed, 41.7 lb, $999.99 with a code that expires January 1, 2027 (base price $1,199.99; checked October 15, 2026; in stock on ankersolix.com when checked October 15, 2026). The one you will actually carry to the kitchen. Anker SOLIX, not Anker.com retail. See Anker SOLIX C2000 Gen 2 on ankersolix.com.
- Jackery Explorer 2000 Plus: 2,042.8 Wh, 3,000 W continuous, 61.5 lb, $1,429 for the kit (Explorer 2000 Plus + two SolarSaga 100W mini panels). In the 2 kWh comparison, not our default pick. In stock on jackery.com as of October 12, 2026; no standalone unit is listed. Refurbished kits exist; we do not quote them as the featured price. See Jackery Explorer 2000 Plus kit on Jackery.com.
Jackery and BLUETTI prices checked October 12, 2026 on the makers’ US pages; Anker SOLIX C2000 Gen 2 price checked October 15, 2026. The family comparison is Jackery vs BLUETTI vs Anker SOLIX. Picks for each job: the stations we’d buy. Sizing lecture: the buying guide.
This calculator is your page if
- You want hours from a list, not a slogan on a spec sheet.
- Everything on the must have list runs on 120 volts: fridge, internet, lamps, maybe a CPAP.
- You can skip the space heater, or you want the numbers to talk you out of it.
Skip this page if
- The well, the dryer, or the air handler has a vote. That is 240 volts: F3800 or a standby generator.
- You wanted a rooftop or a Powerwall. Out of scope: about.
Featured store links: See BLUETTI AC200L on bluettipower.com, See Anker SOLIX C2000 Gen 2 on ankersolix.com, See Jackery Explorer 2000 Plus kit on Jackery.com. We are not earning commissions from these brands today; store links go straight to the maker. Disclosure.
Nobody here metered your fridge, your CPAP, or your lamps. This is arithmetic on planning watts plus dated spec sheets. Check the live product page before you spend four figures. Method: how we work · corrections: contact.