My 4 kw generator uses 1.25 gallons an hour under full load.
My generator must be more efficient. Had to go 2 days just using for fridge, freezer tv and lights, so 1 quart for 4 hours was my experience. Not full load for sure.
The Honda 3200 generator will run 3.3 hours at rated load (2600 watts), and would use 1.2 gallons. Youâd need it to put out rated power to charge an EV.
I couldnât say what mine uses but seems like I had to fill the tank about every two hours running an angle grinder and paint sprayer.
From what I can find, an EV gains about 4-5 miles per hour of charging on 110v. So youâll be VERY limited in how far you can drive with a generator on your bumper. More info here:
Electric Vehicle Charging Speeds | US Department of Transportation
That violates physics. There is no way that generator pumps out 3.2 Kw for 20 hours on 1.25 gallons of fuel. That would mean your generator is 180% efficient which it isnât
Got to get a Tesla and try it out I guess. As I said not at full capacity, Still got 4 hours a quart for tv freezer lights and refrigerator. Did not even ding idle mode.
Your low fuel consumption was because those items donât draw 3200 watts so your generator wasnât running at high load.
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Iâve seen people use inverter generators on youtube, which as far as I know put out perfect 60 cycle AC. Traditional gasoline generators donât maintain perfect 60 cycle output. It could vary from 63 to 58 cycles per second depending on load. Some EV chargers may stop charging if the frequency varies too much. Probably some pointless feature. But itâs interesting, because when the electrical grid becomes over loaded, the frequency drops slightly. It might drop to 59.9 cycles per second. When this happens he utility has a short time to shed some load before the power plants shut down and the whole grid shuts down. An EV could be made to detect this condition and stop charging.
A lot of people have had trouble because some generators donât have the ground connected to the neutral. Itâs not needed, and it potentially makes things more dangerous, but Teslas wonât charge with an open ground. Itâs amazing how little many EV owners know about electricity. Maybe itâs not a coincidence.
A lot of those statistics exclude the cost of the battery or the amount of pollution generated to produce a battery in their calculation. Here is a good video on the topic: https://www.youtube.com/watch?v=sytWLB4-W-M The cost of coal is far less than oil, so an EV is cheaper to operate compared to gasoline when oil prices are high. From a pollution perspective, the fact that coal is much cheaper than oil doesnât mean it produces far less pollution compared to oil. So EVs are potentially making more pollution.
Thatâs about right. 1/8 of a gallon per kWh is what itâs supposed to be for a gasoline engine near full load. Add the loss from the alternator and thatâs right on. For two stroke itâs 1/6. For diesel itâs 1/12 of a gallon give or take depending on compression ratio.
Idle fuel consumption is a lot less even with a cheap 3600 RPM generator, but idle fuel use is highly depending on the number of cylinders. Avoid a 2 cylinder generator if possible unless you run it heavily loaded most of the time. Because the idel fuel consumption will be nearly double!
Be patient George, after the warranty has expired people will come here to ask you how to replace a drive motor assembly.
Is that your idea of a do-it-yourself repair?
Honda generators are more efficient than most otherËhomeowners portable generators. They use inverter technology and cost about 2 and one half time as much as cheaper brands. Even they over rate the capacity for advertising purposes, hence the"3200 Honda " having a maximum steady run output of 2600 watts. Another factor is the largest outlet of your generator. Is it 15 or 20 amps. So either 1650 or 2200 watts and if your Tesla demands more tha that you generator will just blow a fuse or burn up wiring. Also you will have to shut down to refuel or take a chance on spillin gasoline on a hot engine. It masy take long enough to have to change oil also. My generator call for 25 hour oil changes.
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I keep hearing about types of batteries using different elements as the basis other than lithium. Maybe it will happen, maybe not. I do know that many EV batteries are substantially recyclable. At least lithium does not vaporize into the atmosphere upon use, though most types of mining can be toxic. Lithium is less likely to cause a fire than gasoline, but the fire can be difficult to put out.
The ICE in a generator is no doubt less efficient and more polluting than the ICE in a modern âconventionalâ car.
So IMHO itâs a pointless exercise to even consider except for emergencies.
Batteries based on sodium instead of lithium?
Honda generators are more efficient than most otherËhomeowners portable generators.
True, but only when running below full output. Most inverter generators have the ability to regulate engine rpm based on load. So at less than full output, they can dial back the engine rpm to match the load and save some fuel over generators that just run full throttle all the time.
If compared apples-apples (full load output), the inverter generator will be less efficient than one without that feature. The reason being, there are always losses in power conversion. The inverter generator has two additional conversions; AC->DC->AC and that has a price. Its advantage is in providing cleaner power for sensitive electronics.
if your Tesla demands more tha that you generator will just blow a fuse or burn up wiring.
Part of the charging system involves a charging controller. The controller is connected to the AC feed and negotiates with the carâs on board system to set the charge rate. The controller is programmed to know what is feeding it and maintains a rate well below the maximum for a given feed circuit. If you have a 50A breaker, the controller will be set for maximum of 40A delivered to the car.
A small portable generator is impractical for use in recharging an EV. It would be like refilling your gas tank with an eye-dropperâŠ
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How do you figure that? Letâs assume that the ICE generator has a catalytic converter on it. The technology does exist for small engines with carburetors as a bolt on muffler attachment. That takes care of most of the pollution problem. The efficiency of the the generator engine is nearly 15%, since it is operating at near full load. In a car the engine is only operated at partial load most of the time, bringing its efficiency down to well under 10%.
That means that if the alternator on your generator and the charging system in the EV and the battery cycle loss is less than 33%, then charging your EV with a generator is more efficient than driving your typical 4 cylinder car. Of course this does not take in to account the cost of the battery in the EV, which is over twice the cost of all the electricity it can supply over its entire life compared to current commercial electricity rates.
The real winner in all of this is the gasoline or diesel hybrid vehicle!
Show me. Computer controls make car ICEs very efficient. The Prius hybrid approaches 40% efficiency.
The generator isnât thermally regulated because it is air cooled, not water cooled. The compression ratio is much lower than a modern auto, has no variable valve timing, and has a far less accurate fuel delivery even if fuel injected plus a modern 10 speed automatic transmission and throttle-by-wire can keep the engine close to its greatest efficiency point.
So from that, Iâd disagree that the gennie is more efficient.
Nice to see you back TwinTurbo.
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What Prius is 40% efficient?
I was being a bit conservative to the benefit of EVs. Gasoline engines that require premium gasoline can exceed 15% efficiency. Having to run premium is not cost effective. Gasoline direct injection is another thing that could improve efficiency but I havenât looked in to it much. Here is Wikipedia on Engine Efficiency:
Mustangman,
The lower compression ratio does make the generator less efficient. It also lacks computer controlled ignition timing further reducing efficiency. The temperature shouldnât have a big impact on efficiency. It doesnât need variable valve timing nor does it need accurate fuel delivery across all engine speeds because it only runs at one speed under one load condition.
The comparison still holds true even with more advanced engines. More efficient car engine technology can also be applied to generators. Miller makes a generator welder with an EFI option. Maybe a gasoline direct injection version is next?
What you can do with a generator is get a diesel generator to charge your EV. Stationary generators are usually diesel due to the large efficiency improvement. Think 2/3 the fuel consumption! And that fuel is tax free.
Welcome back long time no see. 
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Here you go:
Next Toyota Prius Hybrid: 40-Percent Thermal Efficiency From Engine, Toyota Says (greencarreports.com)
And this is strictly the ICE efficiency, nothing to do with the hybrid system.
Your own wiki quote proves you wrong.
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