Watts and watt-hours answer different questions
Inverter watts decide whether equipment can run and start. Watt-hours estimate how long a battery can supply it. A large energy figure does not fix an undersized inverter, and a large generator peak does not guarantee enough continuous output.
- Add only loads that run simultaneously
- Identify the largest motor start-up requirement
- For batteries, model usable energy and recharge between jobs
Safety is part of the specification
Fuel-powered equipment must not operate in a closed vehicle or unsafe location. Electrical protection, earthing arrangements, weather exposure and extension leads require manufacturer guidance and may require a qualified electrician.
- Plan exhaust direction and ventilation
- Keep fuel away from heat and ignition sources
- Use cables and protection intended for the load and environment
Compare the whole-day operating cost
Purchase price alone misses fuel, battery degradation, servicing, downtime and the time spent charging or refuelling. A hybrid operating plan can be better than oversizing one source.
- Model the busiest realistic day
- Price maintenance and replacement over time
- Keep a documented fallback when the primary supply fails
Compare the workable approaches
| Approach | Best for | Check before buying | Main trade-off |
|---|---|---|---|
| Customer mains | Lean starts and predictable sites | Permission, circuit suitability and cable safety | Dependent on each location |
| Battery power station | Quiet, intermittent electrical loads | Continuous output, surge and usable Wh | Finite runtime and recharge time |
| Generator | Longer independent high-load work | Continuous/peak rating, fuel and safe operation | Noise, exhaust and servicing |