Has anyone thought about using one of the new inverter style gensets to improve MPG by continously charging the HV batteries?

Say a ~9 HP 5000 watt generator mounted on a tagalong single/swivel wheel trailer and powered by "home-brewed" CNG, Compressed Natural Gas.

I'd have to think that any improved MPG would be offset by the extra weight you are pulling and the drag of the trailer.

We're probably talking about a max of 100 lbs including the trailer itself and insofar as drag is concerned the trailer is nicely, neatly, tucked in behind the towing vehicle's wind shadow, drafting as it were. Not that the trailer would have enough frontal profile to create and significant level of drag to begin with.

And keep in mind that the CNG is being compressed from your natural gas supply at home, relatively inexpensive and NO road taxes. Inverter style gensets operate at whatever RPM level the demand load dictates, Idle when the batteries become fully charged.

Assuming you could hack into the battery charging system, what would be the "increase" in mileage versus total cost of doing this?

First you would have the additional expense of the generator, the trailer, the CNG tank and all the wiring/plumbing issues to make this work. You would then have the additional aggravation of towing a trailer (those short trailers are a ***** to back up) and you would be limited as to where you could travel due to transporting the CNG tank.

So, if you factor in all the costs of the hardware plus the cost of the natural gas you would have to burn, would it really increase the efficiency of the vehicle? I'm sure you would travel more miles per gallon of gasoline burned but your cost per mile travelled would increase for a long time.

JMO of course.

By your measure none of the hybrids are worth the additional expense.

The object is not so much to save money but to save fossil fuel and keep the earth's oxygen CLEAN for our great-granchildren.

You need to look up single, swivel wheel trailers. No problem backing those.

NO!
This is a very bad idea.

1. you will spend a lot of money ( already mentioned )
2. you will pollute the environment more
3. you will kill your battery sooner
4. you will probably NOT get any more MPG
5. your vehicle (and those around you) will be less safe
6. you will void your vehicle warranty

Just use the DRIVING skills discussed all over this group.

I'm getting 50+ MPG out of my Ford Escape Hybrid with NO engineering mods.

-John

1. ~$5,000.00 tops.
2. Running a 9 HP engine to recharge the batteries will contribute a lot less polution than the I4.
3. Battery "wear" rates are a lot lower than ICE wear rates.
4.Running a 9 HP engine to recharge the batteries is one hell of a lot more efficient than running the I4. Reduction of "run" times of the I4 should be substantial.
5. And if I put the genset inside the MMH as cargo, what then?
6. Only if I "tell"

I don't plan to change my driving style/method to accomodate a stupid hybrid firmware design.

I don't think it is a good idea. Aside form the aforementioned danger, it will violate your warranty, shorten the life of your battery, not to mention it would require a certain amount of knowledge of the hybrid battery system that few people have. I also don't know how efficient these generators are, and besides you are just burning a different type of fuel, albeit cleaner than gasoline. I think maybe you could look at getting some photovoltaic panels to mount on the roof. I know there is a company that was selling them for the Prius. I think they improved fuel economy by like 10% or something. They were a few thousand $'s but that doesn't seem to concern you at this point.

Still, it seems strange that you would rather spend $5000 building a CNG generating trailer rather than just changing your driving habits. If your priority is reducing use of fossil fuels (and I would consider CNG a fossil fuel too) then you should be willing to change your driving habits.

-Tim

2006 Mercury Mariner Hybrid AWD
Black with Pebble interior
Premium Package with Nav & Moonroof



Current ODO: 26,152
Typical Drive: 20 min crosstown in heavy traffic (3.5mi there and back twice a day)


532 Gallons of gas saved
That's 10,642 lbs less CO2 emitted

Heck, if someone is able to do this, it'll be a great experiment, and data point....might find some FE that no one knows because it's never been tried! It's all speculation until someone tries.

The ICE will come on more often than you think.... because even if it isn't needed to charge the HV battery, it will be needed to keep the system (esp. the catalyst) up to operating temperature. Also, if you go much more than 30mph.

You may also wind up wasting fuel for the generator if the battery is full and won't take any more charge.... and in fact, that would be another instance where the ICE would spin up, with a full battery and under deceleration.