About Wattcellar
Free tools for planning an outage: how long a power station runs what matters, what size to buy, and how fast the sun refills it where you live.
PublisherBockius Ventures LLC, Texas, USA
Last updatedOct 18, 2026
What this is
Station boxes print a capacity in watt-hours. What you need to know is different: how many hours your fridge, CPAP and Wi-Fi will keep going, and whether the sun can catch up. These tools turn one into the other and show every step, including the losses that makers' headline numbers leave out.
Where the numbers come from
Appliance watts come from ENERGY STAR's certified-product data and from manufacturers' own spec sheets and manuals, each linked and dated. Station specs and prices come from each maker's U.S. store. Peak sun hours come from NREL's PVWatts v8 (the lab is now named NLR). We did not lab-test any station. Where a figure is a rule of thumb, such as start-up surge, the page says so. Full list: Methods and sources.
How the site is paid for
The tools are free. Some links to station makers may become affiliate links (see the affiliate disclosure), and we may add clearly marked display ads later. Neither changes a number.
Who publishes it
Wattcellar is published by Bockius Ventures LLC, a Texas limited liability company. Corrections are welcome at hello@wattcellar.com.