I need estimated wattage for an 800 sqft home. I'm going totally off grid.

Asked by Mike Toney
Rutherfordton, NC

no hot water heater,water pump.I need to power a side by side fridge,small tv,laptop,washing machine,microwave,small ac,and around 10 lights counting the outside ones. Mabe a small bilge pump to ocassionally fill water storage barrels for shower.I will be totally off grid. number of batteries?


Sean Lintow Sr

Answered by Sean Lintow Sr

Naperville, IL

SLS Construction & Building Solutions

July 1, 2013

Well first off congrats and best of luck.

While I could throw a number at you, it would be completely worthless. There are numerous calculators and spreadsheets on line where you plug in each of these devices and how many hours per day they will be running to come up with a number that might actually work.

As for batteries, well you need that number above and then you've got to figure out how much of a buffer you might need. A good starting point would probably be around three days in case of cloudy or snowy conditions and you still might want a backup generator.


For more information:

Read "Going Off-Grid in the 21st Century, Initial Calculations for Sizing" a post on Sean's blog.

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