Pillar 3
Generator backup strategy for resilient homes
Generators are still the best dollars per kWh for multi day outages and high surge loads. This pillar helps you choose a fuel strategy, size the unit, and integrate safely with an interlock or transfer switch.
When a generator is the right answer
Long outages
If you need 48 hours or more, a generator plus modest batteries is often the best value.
High surge loads
Well pumps, large HVAC, and shop equipment can make battery only builds expensive.
Budget constraints
You can get reliable power per dollar faster with a generator, then layer solar and storage later.
Cold weather performance
Batteries lose usable capacity in the cold. Generators do not, if properly maintained.
Generator sizing tool
Enter your critical load watts and expected surge. This recommends continuous and surge sizing with headroom. Treat this as planning guidance, then validate with real load data.
Enter inputs above, then press Calculate generator size.
Always follow local electrical code. Backfeeding without an interlock or transfer switch is dangerous and illegal.
Safe integration options
Choose the simplest safe integration that matches how you want to operate during an outage.
Panel interlock plus inlet
Best value. Manual operation. Works well for prosumers who can manage loads.
Manual transfer switch
Simplifies operation and helps prevent overload if configured for critical circuits.
Automatic transfer switch
Premium convenience. Ideal for whole home standby units with fixed fuel.
Hybrid: generator plus batteries
Batteries handle short outages and ride through starts. Generator handles long runtimes.
Fuel strategy
| Fuel | Pros | Cons |
|---|---|---|
| Natural gas | Unlimited runtime, clean operation | Depends on gas utility availability and pressure during regional events |
| Propane | Long storage life, good for rural | Tank sizing and refill logistics |
| Gasoline | Portable and cheap units | Storage stability and safety concerns |
| Diesel | Efficient, strong surge power | Fuel storage, noise, maintenance |
If you do not have a fuel plan, you do not have a backup plan. Pick a fuel strategy before you buy a generator.