Which home battery to choose: a backup power calculator
To choose a battery for your home, you need to know two things: which appliances you want to keep running during an outage, and how long the power is usually out. Our backup power calculator works it out in about a minute. You pick your appliances, set the outage length, and it sizes the right LiFePO4 capacity (in kWh) and a matching battery model. Genixgreen supplies energy storage systems in Ukraine from a warehouse in Odesa, so equipment arrives in a few days, not weeks. The calculation is free, with no obligation.
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After the calculation, our engineer confirms the exact battery and wiring layout.
Frequently asked questions
How many kWh of battery does a home need?
Most homes are covered by 5–7 kWh if you back up only the essentials (fridge, lighting, internet, charging). The exact figure depends on the total power of the appliances you want to run and how long the outage lasts: the more power you draw and the longer it runs, the more kWh you need. The calculator works this out automatically and shows the capacity you need right away.
How long will the battery last during an outage?
It depends on the load. For example, a 5 kWh battery can power the essentials (fridge, a few lights, router, chargers, around 200 W on average) for up to about 20 hours. The more high-power appliances you add, the shorter the runtime. The calculator shows the estimated runtime for your selection and how many outages the system covers before it needs a recharge.
Why LiFePO4 rather than another battery chemistry?
LiFePO4 (lithium iron phosphate) is safer than other lithium chemistries: it stays stable under heat and is far less prone to overheating or fire. It also withstands several thousand charge cycles and tolerates deep discharge, so it holds up over years of daily use. For home backup it is a strong balance of safety, lifespan, and cost.
Single-phase or three-phase: which should I choose?
Most homes are fine with a single-phase system (230 V); it covers everyday use. Three-phase is only needed if you have high-power loads that draw a big spike of current at startup (for example a pump or a powerful air conditioner) or a large house with a total peak above 8 kW. The calculator shows your peak demand and suggests which hybrid inverter fits.
Is the system hard to install? Who does the work?
Installation is done by a qualified electrician; for safety reasons you should not wire the system into your home grid yourself. We provide the specification, the wiring diagram, and technical support, and equipment and spare components ship quickly from the warehouse in Odesa. After the calculation, leave a request and we will help you find an installer or agree on the wiring layout.
* This information was prepared by Genixgreen engineers, a manufacturer of energy storage systems since 2011. Final sizing and the wiring layout are confirmed by our engineer.