LMF5000
Mechanical
- Dec 31, 2013
- 88
I refer to the tiny suitcase-style generators with plastic cases that you take with you on barbecues, like the Honda EU1000i and all its competitors from Yamaha, Kipor, Hyundai and so on.
In general, they seem to have single-cylinder 4-stroke engines of 50-100cc, weigh 10-20kg, make 60-90 dB of noise, cost €400-1000 and output just 700-1100 watts.
In contrast, a modern-day naturally-aspirated car engine is hitting 100 bhp per liter. A 100 bhp engine weighs around 70kg (including gearbox), can make over 800W while idling near-silently (calculated from 70A alternator output * 12V), and costs maybe €5000 new (engine alone).
By those specs, a 50cc generator engine should be able to make around 5bhp (3.7 kW), and assuming 90% conversion efficiency should easily reach 3kW sustained output at line voltage.
Why are generators still so backward in terms of technology? Why has no manufacturer created a 3-5kW unit that can be easily carried with one hand (say by using a very small petrol engine and adding a small lightweight turbocharger (as they are doing with European cars like the Fiesta Ecoboost these days in an attempt to save fuel)?
In general, they seem to have single-cylinder 4-stroke engines of 50-100cc, weigh 10-20kg, make 60-90 dB of noise, cost €400-1000 and output just 700-1100 watts.
In contrast, a modern-day naturally-aspirated car engine is hitting 100 bhp per liter. A 100 bhp engine weighs around 70kg (including gearbox), can make over 800W while idling near-silently (calculated from 70A alternator output * 12V), and costs maybe €5000 new (engine alone).
By those specs, a 50cc generator engine should be able to make around 5bhp (3.7 kW), and assuming 90% conversion efficiency should easily reach 3kW sustained output at line voltage.
Why are generators still so backward in terms of technology? Why has no manufacturer created a 3-5kW unit that can be easily carried with one hand (say by using a very small petrol engine and adding a small lightweight turbocharger (as they are doing with European cars like the Fiesta Ecoboost these days in an attempt to save fuel)?