We seem to all know instinctively that when it comes to portable power like pressure washers and lawn mowers, gasoline engines are more powerful than electric ones. But why?
After all, much of heavy industry chooses electric motors (not gas engines) to power conveyor belts, saw mills, ore reclaimers and more. So what’s the deal when it comes to portable machines?
- In residential power equipment electric machines are limited by the electricity available to them from your home wall outlet or from their battery.
- Your home has a breaker in the electric distribution board that will blow if you try to draw excess current.
- Gasoline engines burn gasoline for energy and there is no breaker to blow.
- Gasoline fuel has more energy per mass than batteries.
- If you can design a pressure washer with a larger electric motor and you can plug it in to a much higher current connection (like at a mining site or manufacturing plant) then you can have more power. Heavy industry has much higher load electricity distribution network than your home. They can draw enough to power heavy duty electric motors to power thousand foot long conveyor belts and other high power requirement processes.
- To put some numbers to it: Electric pressure washers can have about 1.5 hp once you account for inefficiencies… You can draw 12 – 15 Amps from your home outlet. 12A at 120V is 1440 Watts or 1.93 hp.
- Small gas engines in pressure washers are 3 – 4 hp. The Honda GX160 engine used in several of the top 10 bestselling gas pressure washers has a power output of 2.7 – 4.7 hp at 2000 – 3600 rpm.