Would double battery = double mileage?

[dcb]

Originally Posted by jamesqf

No, "sensibly" means minimizing the use of gasoline, while still keeping the benefits of unlimited range and not being stranded when the battery runs out.

NO, that is not the context you first used the term "sensibly" it in at all!!! It was in response to my statement about efficiency, and you said "Not if it were done sensibly", see here:

Originally Posted by jamesqf

Not if your system was designed sensibly: most of the power generated should go straight to the drive motor, with only the excess over the amount needed to move the car going to the batteries and incurring charge/discharge losses.

What you are now describing in post 60 is conveniences and "insurance" of sorts, not efficiency. My objection has always been the efficiency of the jury rigged $500 generator series hillbilly hybrid.

[jamesqf]

Originally Posted by dcb

NO, that is not the context you first used the term "sensibly" it in at all!!! It was in response to my statement about efficiency, and you said "Not if it were done sensibly", see here:

If you read for meaning rather than going on a nit-picking expedition, you'll see that we have two things going on.

One, is it more "sensible" to have a pure electric car (with attendant range limits & risk of stranding), a pure gasoline car (using fossil fuel vs potentially renewable electricity), or a hybrid, combining advantages of both? I obviously think option 3 works pretty well.

Two, if you decide for the third option, is it sensible design to run all electricity produced through the batteries, incurring charge/discharge losses?

[Air-Hybrid]

BEV with small ICE pusher-trailer with CVT for highway assist or going more than a few dozen miles?

[jamesqf]

Originally Posted by Air-Hybrid

BEV with small ICE pusher-trailer with CVT for highway assist or going more than a few dozen miles?

Still gets you into the stranded zone if you e.g. don't happen to have the trailer hooked up the day a major crash closes your normal route and you have to detour 20+ miles out of your way - which has happened to me.

[dcb]

I guess turning around or waiting aren't sensible compared to stranding yourself. I'm starting to think the onboard generator could replace tinfoil hats too.

[jamesqf]

Originally Posted by dcb

I guess turning around or waiting aren't sensible compared to stranding yourself.

Sure, if you know that's what will happen. But sometimes you see a cop or flagger directing traffic off on to a detour, and you don't know how long the detour will be. Then too, there are times when I start out not knowing exactly where I'll be driving to (e.g. running errands and you have to go to several different places to find stuff).

If you lead a regular life, making the same 22.7 mile commute to the office every day and never going anywhere else, a pure BEV should suit you just fine. But not everyone lives that sort of life (or wants to). Why should we forego an option that would increase our overall mpg?

[dcb]

but you are suggesting it is "sensible" to carry a generator with you everywhere you go, and to rig up heat to your air cooled generator apparently, just in case you fail to plan or think. That is akin to towing a scooter in case your car runs out of gas. It will hurt your mpge during the other 99.999999% of the time when you operated your heavy equipment correctly.

The sensible thing is to not run out of gas in the first place. The next sensible thing is to be efficient about extending your range. Series here is only good for "emergencies", whereas a long hiway trip can be handled most efficiently by a parallel setup. You can plan, even desire, to use your range extender if it is efficient and something you can unbolt when not needed. If parallel has gears it can offset battery usage around town as well.

Carrying it around "just in case" is just bad planning, not sensible. It will not improve overall mpg, because you are adding it to a BEV in this case, you will go from "infinity" mpg to something less than infinity mpg if only in evaporation. Use your head...

[neilzero]

If you have a 20 kw lead acid battery and you add a 22 kw lithium ion battery, you can probably double your range from 40 miles to 80 miles. The lithium ion battery only adds about 5% to the total weight. A generator trailer with a 50 pound battery, extends your range, probably, until you run-out of fuel for your trailer = 1000 miles. Possibly your generator trailer can have two powered wheels which are energized when climbing steep hills and when you want rapid acceleration, besides providing some extra storage space which is often useful on long trips. A trailer with powered wheels can also provide some dynamic breaking down steep hills and for quick stops. You probably want to leave your trailer at home for driving around town, but it can also provide some emergency power for your house, if the utility is blacked out. Neil

[Frank Lee]

OK.

Break, breaks, breaking = BROKEN STUFF.

Brake, brakes, braking = SLOWING AND STOPPING.

Can we make this a sticky?!?

[codenamezero]

Guys, if you need to drag around a generator trailer, you may as well just get a hybrid car and just run it on battery, because a hybrid already has a gasoline engine built in, that is essentially your "generator trailer".

The whole point of getting an EV is to be as gasoline free as possible. Again, if you ONLY compare the possibilities of extending the range, it boils down to the following:
- Adding more battery
- Adding a electric generator
- Adding a generator trailer

We've already ruled out that adding more battery is not beneficial due to its weight and it will be expensive, not to mention the usage is one charge only, if you depleted the battery, you will have to stop and recharge. So adding battery to increase the range is a no-no.

Now if you look at the next 2 possibilities, they are basically doing the same thing. They both takes gasoline and convert into electricity. Comparing them side by side, you can see the clear winner is the portable electric generator...

Weight (lighter): portable generator win
Size (smaller): portable generator win
Re-usability (backup power): portable generator win
Cost: MAYBE generator trailer if you build the whole thing yourself, otherwise for non-DIYer, there is no such thing as generator trailer that is ready for you to haul around. So portable generator win...
Availability (where to buy): portable generator win
Capacity (re-fueling): Technically, generator trailer have a bigger capacity, but that's also because the engine burns hellalot more gasoline than portable generator.
Efficiency (way greener): portable generator win