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Energy Questions

Should I Keep My Diesel Generator With Solar?

How a battery and the right inverter use your generator as a last resort, and cut its fuel and running hours.

The short answer

Yes, keep it. With a battery and an inverter that can manage a generator, solar and the battery carry most of the load, and the generator starts only when the battery runs low or the load is too big. It runs far less, so you spend less on fuel and servicing, and you still have it for long outages.

Generator as a last resort

Solar runs the load during the day and fills the battery. The battery carries the night. The generator starts automatically only when the battery runs low or the load is more than the system can supply, then stops when it's no longer needed.

What it saves

  • Fewer running hours, so less diesel
  • Longer gaps between services
  • Quieter nights, with the generator off most of the time
  • Backup kept for long outages and cloudy spells

What it needs

An inverter with a generator input, set up to start and stop it, and a battery sized to carry the night. On grid-connected sites, the generator becomes backup for outages; on off-grid sites, it covers long cloudy stretches.

Solar and batteries for farms

Your Savings

See what solar and a battery would save you, with your state's rebates applied.

Common Questions

Can my existing generator work with a new battery?

Usually, if it can be started remotely and suits the inverter. We check your generator and tell you if it needs a controller or changes.

How much diesel will I save?

It depends on how much of the load solar and the battery can carry. On sites that ran the generator daily, the savings are usually large. We estimate it from your fuel records and loads.

Is an off-grid system worth it?

Where the grid is far away or unreliable, often yes. We compare the cost of off-grid with solar, a battery and a generator against keeping the line.

Ready to transform your energy future?

Tell us about your home, business or farm. We'll design a solar and battery system around your bills, with every rebate applied.

  • RenewableRooftop and ground-mounted solar, sized to you.
  • StorageBatteries that keep your solar working at night.
  • EfficientSmart systems that cut what you pay the grid.