Whole House Battery Backup system: Recommendations?

Hello, I am seeking a WHOLE HOUSE BATTERY BACKUP - but charged directly from the grid. The purpose is simply to have 5+ days of back up power when power outages occur …not looking for a solar solution. We are on First Energy in NW Ohio.

Please advise of which whole house battery you recommend?


First before you can size a battery for your needs you need to know how much energy you use on average per day? This is known as your daily electricity consumption and is measured in kWh (kilowatt hours) It might be listed on your utility bill?

Once you know this vital piece of information you can determine what size battery is suitable. (It is usually around 15 to 25kWh per day for an average 3 bedroom home)

I’m guessing a battery big enough for 5 days will probably be quite large and expensive. It would make sense to also install solar (unless it’s covered in snow?)

Our power outages typically occur in the winter due to ice storms - solar ability at such times is negligible. Let’s assume 20kWh per day.

In that case you would need about 100kWh of battery capacity! Modern lithium batteries cost around $750 per kWh so just the battery alone would cost around $75K. Then you would need the multi-mode inverters and other equipment.

Basically you would need a powerful off-grid inverter to be able to charge battery of that size and enable backup power. These inverters can be used without solar and setup for backup power. In Australia Selectronic is the best option, but in the US, the high-performance inverters from Outback Power or SMA would be a good choice.

As for batteries, the best options are the same as those used for off-grid systems. Simpliphi is a well known, high-end battery made in the US.