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The campsite is dark, the phone is dead, and the cooler fan has stopped. A solar generator calculator turns that moment into a plan: list the loads you plan to run, add their watts, work out the watt-hours, and match the totals to a station that can carry them. The steps below show how the figures fit together, using the stations in the listings as the worked examples.
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How a solar generator calculator works
A solar generator calculator takes the loads you plan to run and turns them into the figures that size a station: watts and watt-hours. Watts set whether the station can run a load at all, and watt-hours set how long it can keep running. The Anker SOLIX C1000 Gen 2 lists 2,000W of output with 3,000W of peak power and 1,024Wh of capacity, while the HOWEASY lists 300W of output and 222Wh of capacity. The gap between those lines is the whole job of the calculator: match your totals to the station, not the station to a guess.
Step 1: List the loads you plan to run
Write down every load you plan to run from the station, with the watts each load draws and the hours you plan to run it. Count the small loads as well as the large ones: phone chargers, lights and fans add up beside a fridge or a power tool. The HOWEASY lists 9 devices running at the same time, and the Anker lists output through 9 ports, so a station can carry a set of loads at once when the watts allow it. Keep the list to the loads you will actually run, and leave out anything that stays on mains power.
Step 2: Add the running watts
Add the running watts of the loads you plan to run at the same time. That total has to sit under the station’s output: the HOWEASY lists 300W of output, and the Anker lists 2,000W of output. A load that draws more than the output will not run, no matter how much capacity the station holds. Check the running watts of each load on its own label, and use the running figure rather than the peak figure for this step.
Step 3: Turn watts into watt-hours
Multiply the watts of each load by the hours you plan to run it, then add the results. That total is the watt-hours the station has to hold. The HOWEASY lists 222Wh of capacity, and the Anker lists 1,024Wh, so the stations cover very different totals. If your total sits above the capacity of the station you own, drop a load or shorten the hours before you buy a larger unit. See the amp hours vs watt hours guide for how the units relate.
Step 4: Check surge, outlets and solar recharge
Some loads pull a short surge when they start, so check the peak figure as well as the output. The Anker lists 3,000W of peak power against 2,000W of output, which covers the startup surge of a motor-driven load. Then check the outlets: the HOWEASY lists 2 QC 3.0 USB ports, 1 USB port at 5V 2.4A, 1 USB-C port at 65W, 3 DC ports at 12V 10A, and 2 3-pole output sockets at 300W, with a 110V AC outlet. The Anker lists output through 9 ports, with UPS backup for vital equipment. For recharge, the Anker takes up to 600W of solar at 60V max and recharges fully in 1.8 hours, and it recharges from AC at 1,600W in 49 minutes. The HOWEASY bundle includes a foldable 60W solar panel and charges by solar at 18-24V, by AC wall adapter or by car charger. See the solar panel output calculator for the solar side of the recharge.
Ways to make the capacity last longer
- Run the largest load alone: start the motor-driven load on its own, then add the small loads once it is running.
- Use the app to watch the power: the Anker app monitors, controls and schedules power, so you can see what each load draws and turn loads off from the app.
- Top up with solar during the day: the Anker takes up to 600W of solar, and the HOWEASY bundle includes a foldable 60W panel, so daylight puts power back while you use the station.
- Keep the station charged between trips: the HOWEASY listing advises charging the battery at least every 1 to 2 months when the generator is not in use.
FAQ: power away from the grid
What size solar generator do I need for camping?
It depends on the loads and the hours. The HOWEASY lists 222Wh of capacity and 300W of output for small devices, while the Anker lists 1,024Wh and 2,000W of output with 3,000W of peak power for larger loads. List the loads, work out the watts and the watt-hours, and pick the station whose capacity and output cover those totals. See the power station types guide for the kinds of stations on offer.
How do I work out the watt-hours I need?
Multiply the watts of each load by the hours you plan to run it, then add the results. The total is the watt-hours the station has to hold. Compare it with the capacity the listing states: 222Wh on the HOWEASY and 1,024Wh on the Anker. If the total is above the capacity, drop a load or shorten the hours.
What is the difference between running watts and peak watts?
Running watts are what a load draws while it runs, and peak watts are the short surge it draws when a motor starts. The Anker lists 2,000W of output and 3,000W of peak power, so the peak figure covers the startup surge while the output figure covers the steady load. Size the station on the output figure, and check the peak figure against the largest motor you plan to run.
How long does it take to recharge a solar generator?
It depends on the input and the station. The Anker recharges fully in 1.8 hours on 600W of solar at 60V max, and in 49 minutes from AC at 1,600W. The HOWEASY charges by solar panel at 18-24V, by AC wall adapter or by car charger, and its bundle includes a foldable 60W solar panel. Check the solar input and the AC input the listing states before you plan around a recharge time.
Related solar guides
See the power station types guide, the high capacity portable power stations guide, the best portable power stations for home backup and the power stations hub.
