Generator vs power station vs home battery: 10-year cost
Which backup option is cheapest over ten years depends mostly on how many hours a year your power is out. Enter the prices you were quoted (we store none) and your outage hours, and compare. Leave an option's price empty to leave it out.
How this is worked out
- Total = purchase + install + every year of fuel or recharge energy, upkeep and any replacement, over the horizon. Dollars are nominal: no discounting, no inflation unless you set a fuel price rise.
- Generators: fuel burn at your load uses 25% of the full-load rate plus 75% scaled by load fraction. That is a generic assumption; check your model's runtime chart at 25%, 50% and 100% load. Exercise runs are included at a light load. The engine is replaced if its hours pass the life you set.
- Batteries: you pay for the electricity to recharge (delivered kWh divided by round-trip efficiency). A replacement is charged when cycle life or calendar life runs out. Cycle life and calendar life come from the maker's spec sheet; replacement defaults to the purchase price.
- Not counted: solar or time-of-use savings a home battery can earn every day, the value of keeping food and a sump pump safe, resale, tax credits or rebates, and standby losses. A home battery that you also use daily can look very different from this outage-only view.
- All non-price numbers are typical starting values, not measurements. Replace them with figures from the spec sheet and quote for the exact model.
Start with the backup power calculator to find the load and battery size.