Is it plausible (I know that anything is POSSIBLE) to use an engine like this:
http://www.himodel.com/engines/DLE-55_55cc_Petrol_Engine_for_Radio_Control_Aeroplane.html
to connect to a 48 volt generator to charge batteries or to directly run a motor? I am thinking "hybrid". I know these motors run at a higher rpm than most generators but there are always pulleys. They are simple in design, light in weight...but I am not sure if they will run for 15 hours at a time without melting.
An engine, such as the one you describe, could possibly turn an alternator and produce about 3.5 KW of usable electricity. Using this to charge your battery would be possible, but not very "energy efficient", as more fuel would be used than if you drve the vehicle directly with the gasoline engine, and this engine is also a "2 cycle" engine, which is not generally as efficient or reliable/durabe as a similar size/power 4 cycle engine, although it might be somewhat lighter in weight. To charge while cruising, (for "ulimited range") the alternator output should be greater than the vehicle electrical demand, so that there will be excess power available to charge the batteries. Such a system COULD be configured to provide greater acceleration than the gasoline engine alone could provide, because some electric motors can produce 4 or more times their rated continuous horsepower for short periods. (a 4 horsepower electric motor might be capable of 12 horsepower, for 30 seconds)-That might give better performance than directly driving the vehicle with the 5.5 horsepower gasoline engine.-Bob
Robert M. Curry
That engine would drive a generator that would put out less power than the engine itself. 3,500w is terribly optimistic. You build a lighter weight yet more powerful vehicle just by powering it by that engine. That's not a clean engine, isn't the idea of the hydrogen generator to make a CLEAN car? Oh wait, it's also about inexpensive fuel, which this engine doesn't have.
But that's drifting from the most important shortcoming of your plan, which is the fact that this is a very ineffective approach. Running at a continuous RPM where it doesn't fly apart, that engine would probably be 2.5hp, which might give 1,500w, or less. If you're not running off batteries, you can't have more than a 1,500 watt motor, eh? The problem is that people assume that a generator can give slmost unlimited power from some small engine. My relative swears it's possible to build a contraption where he uses his car on some conveyor to build his dyno to speed, then lets a lawnmower engine maintain the system and he generates all his own power around the house. I tell him he MIGHT get one wall outlet of power, and he won't believe me. Nor does he have an explanation of how to get the car away from the conveyor belt afterward.
WHo dares, WINS!!!!
3,500 watts from the specified engine is NOT too optimistic, as the engine is rated at 5.5 horsepower,or over 4,100 watts output. (Such a system is not what I would recommend, however!)-Bob
Robert M. Curry
Thanks! Most likely I would be using an 800 watt 60 volt motor. I realize that there are inefficiencies in this system but the laws and regulations that I am dealing with are even less inefficient. A 50 cc gas scooter would probably be the most efficient, given the distances I want to drive. First of all, while a foreigner can buy a motorcycle in China, s/he cannot buy a license plate for it - have to find a Chinese friend with a driver's license in the same general area to buy it for me. The fee for the place is about US$100 but if I want to ride it inside the city I have to spend more than US$ 3,000 for the plate. If I were stopped, a hybrid with a direct motor to wheel drive would probably be rated as a gasoline powered vehicle but an electric scooter with a generator would still be considered an electric vehicle and would not need the plates.
Yeah, whatever, I only work with generators on shoots, and they never give the 600 watts per horsepower they're rated at. Wind the engine up to get as close as possible and you can tell it won't last.
That RC engine I was probably being optimistic saying it could generate an ongoing 1,500 watts, that crankshaft probably wouldn't hold up long under the load.
WHo dares, WINS!!!!
"Dauntless" mentions that he never gets 600 watts per horsepower from his generators on "shoots".--I have some HONDA gasoline generators that have NO difficulty providing that much power per rated horsepower, into a non-reactive load! One issue affecting how much power is USABLE, that some of us forget, is the POWER FACTOR of the load, because if the device(s) being powered by the generator present a reactive load, with a "Power Factor" that is less than ONE, all the rated watts may not be usable, because of this inductive or capacitive reactive load. Not having used the engine discussed, I cannot say with authority how it would fare, but to me, it is not the best choice.(loads such as air conditioners, fans, other devices with induction motors, or capacitive input filters in power supplies, can be especially troublesome with regard to power factor, as are other electronic devices without power factor corrected power supplies. In some cases, power factor errors can consume as much as a third of the otherwise usable generator power! (some devices also require three times as much power to get STARTED as they use once fully powered on, and generators usually do not like this!)--Bob
Robert M. Curry