Why can't an electric vehicle charge itself?

I know I am just an old mechanical designer who knows close to nothing about electricity but why can't an electric vehicle charge itself? Gen sets can charge batteries, which most are just diesel engines turning a generator that produces electricity, seems as simple to me as hooking a generator to the rotating mass that the electric motors run? Is it that there is just no profit in it? Discuss...

Because.......

Burning coal in the car to power the generator to generate the electricity to recharge the batteries is an extra cost option.

to some aspect they do thru regenerative braking systems.
i have seen some videos posted on facebook they tow a completely dead tesla 1 mile it gave them a estimated 1 mile of driving charge.


from what i assume you are describing attaching a generator to the drive axles it would significantly reduce the driving distance due to drag from the generator.
i am no engineer but you are describing something like making a preputial motion machine that gets endless energy. they have been attempting to make one successfully for eternity.
i would assume it takes a bit more energy to make the electricity that the motor driven by the electricity.

makes me scratch my head also. the 1st ford escapes hybrids had r-gen capacity. should be a walk in the park to make it work. my nephew owns a ford dealership and the chargers ford sold them charge the elec cars to full charge in hardly any time at all.

They do, but then they are called hybrids.

When I worked for Eon I had a Ford Escape hybrid as my company car. It could run electric, gas or both. Since 90% of my commute was highway it was mostly running IC only.

Something like a Tesla uses regen braking to recover some power back, but it's not the same.

Because it takes power to make power. Use power to keep the batteries charged and you don't have any left to power the car.

Regen braking charges during coasting and braking when the motors are being turned and generating power. Energy is returned to the battery, but unless you go downhill a lot it doesn't make a lot of difference in battery range.

No free lunches.

this is inaccurate in regards to a hybrid. They have enough power to charge the batteries and keep the car running down the highway. Speed limit is 75 around here and that Escape had no issue doing it.

https://en.wikipedia.org/wiki/Ford_Escape#Hybrid

If you are referring to a pure electric vehicle, then the best way to keep those batteries charged is to not drive it.

of course a IC hybrid motor can charge the batteries to power the electric motors while driving down the road. that's what they were designed for.

the OP is asking why the ELECTRIC MOTORS can't charge the batteries via generators turned by the electric motors while driving down the highway.
in short it takes more electric power to turn the generators than they can produce. no one has ever built ANY motor than makes more power than it consumes. if they did they would be the richest person in the world.

I guess I got confused by the gen set tangent.

The electric motors used in an EV are also generators, that's how they do regen, I guess if you could hook a tow line to an 18 wheeler you could do what the OP was thinking.

Other than that, conversion losses alone would make is a losing proposition, much less trying to get any useful work out of them

When electric motors and generators were invented/discovered, many people thought it would result in a perpetual motion machine. It doesn't work that way. if you're using an electric motor to run a generator, you lose power due to the resistance of the wiring and connections, without even trying to draw power off to do anything extra like power a vehicle.

When I ran the municipal garage, I was trying to get a test program going with my city, Mack, and Parker hydraulics for Hydraulic Launch Assist for refuse trucks. Residential refuse trucks have a crazy duty cycle: from a dead stop, accelerate at WOT for about 70', then stand on the brakes for 50' to get to the next bin. if you install a hydraulic pump/motor in the driveline and use it as a pump to charge an accumulator during braking to store the energy (fluid under pressure), then release that energy to drive the motor during acceleration, you theoretically can use a smaller engine to power the truck, use less fuel, etc. Sounds great, right? There's a similar system for city busses, but the duty cycle on refuse trucks means by pressurizing the fluid you increase it's temperature as well, and when you do it 500 times a day, your fluid overheats in about 100 stops. You end up with a HUGE reservoir and cooler for the fluid, to prevent that, and the weight of all of that equipment and fluid eats up any benefit of the system.

The bottom line is that gasoline and diesel fuel became the common motor vehicle fuels through a Darwinian process that began in the late 1800's. They are (relatively) stable, can be stored at common atmospheric temperatures and pressures (in quantities from small to huge), allow for refueling with VERY minimal training and no protective equipment, and became available essentially worldwide. EVERY alternative has significant drawbacks in at least one of those areas. You can argue that gasoline is a fire hazard, but it's (again relatively) easy to extinguish. Look at the reports on the wrecked Tesla that took over 4 hours to drown (literally) after it sat untouched in a junkyard. Forget your gloves when refusing your propane vehicle and you can lose a hand to frostbite (imagine letting your 16-year-old kid try it on their own). CNG vehicles require complete purging of the pressure tank before any maintenance work is done, OR a completely explosion-free shop be constructed with enclosed electrical systems, no spark-producing tools, etc. Hydrogen shows the most promise but again the technology is not yet mature enough for mass production.

IN MY OPINION, the move away from fossil fuels is another example of politicians trying to legislate technology. They want what they want (and WHY is a different discussion) without concern that it's not practical in today's world.

Well I believe that nothing has been done too much on my subject is due to money, nothing else. A paradigm shift is what needs to happen, but never will with the present companies in charge, there needs to be new blood with much more thought than even the people at Tesla have even thought of...

There is a way for the vehicle to recharge itself, but the equipment is too large for modern cars that seem to put everything into a compact spot. I have worked on a project with a friend (rip) and had a working model in an older Tesla that not only charged the car, but was able to use all the features. Sadly, he had to disconnect the cars computer and run it as separate system. Then the added weight and lack of space made for it being problematic. With modern equipment and newer technology, I’m sure it’s doable now, just not sure if it would be practical now.

Some automakers plan to put on board generators as "range extenders" to burn gas to recharge the batteries.

"Some automakers, including BMW, are producing electric vehicles with internal combustion “range extenders.” These are essentially efficient generators that can burn gasoline to replenish the battery while on the road. Ram may be eyeing a similar setup for future vehicles."


https://www.motorbiscuit.com/heres-everything-we-know-about-the-electric-ram-pickup-truck/

I look forward to future "range extender" jokes...

It takes energy to create energy, wind, solar, hydro, natural gas, coal and so on.
Basic law of physicists, no one rides for free

I would have thought that would have been in Engineering 101 !!! You can't get more energy out than you put in. HOWEVER, consider that electric motors are also generators. While the motor is used to propel the vehicle, it can generate power when used as a brake or when coasting down a hill. So, if you were going for a long drive and it was all downhill, the vehicle could charge itself. However it would not generate sufficient enegy to make the full uphill return trip

I thought about this way too, for the time being it seems like the only logical way. Electric car pulling a trailer with a 7500 watt generator in it. My 7500 burns 5 gallons in eight hours, would that be enough to keep the batteries charged, don’t know. I also feel the powers that be are pushing this out there banking on someone in the general public coming up with the fix. The old saying “Necessity is the mother of invention”

Years ago sitting in an engineering meeting, two people had the full attention of as they explained in detail how they designed an near indestructible articulated arm for the medical lasers we were manufacturing. All was going well until the junior designer claimed "The arm is so good that we have measured more power out of it than is going in" DEAD SILENCE in the room. OOOPPPSS!! The arm became an industry standard and the design was eventually licensed to a few competitors

[quoteIf you are referring to a pure electric vehicle, then the best way to keep those batteries charged is to not drive it. [/quote]

Has this been told to the folks in Washington??

Electricity is a funny demon. But like the old saying goes: "There's no such thing as a free lunch." Power (or "energy") is ALWAYS lost through friction, heat, resistance, etc.
You'll never get MORE out of what you put in.

A fun experiment is to get a cheapy little 40-amp alternator. Hook it up to a battery source and a regulator and now YOU try to turn that alternator. You might be able to; but not sustainably enough to be useful.
Now, get a 200-amp alternator from a big truck and do the same thing. A small team of dogs wouldn't be able to turn it. You would need the mass of something; like a car - to be able to turn that sucker.

Lots of the electric things have regenerative braking - and this is a wonderful thing. But you can't have it ON all the time - the drag would be immense and you'd be wasting 10x more energy trying to get something out of it.

Why don't race cars have alternators? It's not because they don't have headlights! It's because that little chargin' whirler saps up an easy 5hp. The bigger the alternator, the more hp it takes away!


Personally, I think we should be looking more into Hybrid/Turbine technology. A small Turbine powerplant that has three states: OFF, idle or RUN and therefore can be tuned to run as cleanly as possible. It's only job is to turn a generator that can power an electric motor and maybe a small, backup battery. A multi-fuel Turbine would not only be able to run off of ANY combustible fuel, it can be tuned to run as cleanly or cleaner than any current internal combustion engine; but it's maintenance now drops to ZERO and moving parts/failure rate plummets. Win-Win for the consumer; not so much for the manufacturer.

But I also think we've gotten away from simple reliability. I firmly believe ALL electric cars should have a simple, planetary transmission. Why? Very Simple. A "classic" three-speed or even 2-speed transmission would:

Provide a "PARKing" position that everybody and their dog is used to.
A much simpler reverse function - rather than reversing the electric motor (which requires big, heavy circuit breakers and relays) - just do it hydraulically.
A NEUTRAL position for pushing/towing that not all electrics have!!
Drive for every day driving.
Gear reduction should such an idea be necessary.

But, the other great thing about a simple transmission would be it's fluid pump. I don't think it would be much parasitic loss to have that same pump power a hydraulic power steering unit and a hydroboost brake unit. We could also plumb a heater matrix into the fluid system because the fluid will get warm. Why not dissipate that heat through the cabin rather than have 39 separate electric systems doing all these jobs.

I really think the designers of today believe themselves to be much smarter than they actually are. None of them have ever heard of the phrase "Putting the cart before the horse." They've no idea what a cart nor a horse is.

but think of all those battery companies and lithium mines

What has been proven to work by a skunkworks style team is a windmill mounted on top of a vehicle, hooked to a generator, charging batteries that run the drive motors. As the vehicle moves down the road, the movement through the air spins the windmill, creating more than enough power to run the car. Special, patented, high efficiency blades were required to surpass and defeat the laws of perpetual motion.
When the oil company executives found out about it, they bought out the patent, and destroyed all the technology. The inventor and the three top engineers on the project all committed suicide by gunshots to the back on the same night.
You'd be proceeding at your own risk, but it could be produced. Some of the engineering data and patent drawings are circulating on the dark web if you know where to look.

Keep in mind that both of these would add a tremendous amount of weight over the current electric power brakes and steering - not to mention the power loss of driving them. I'm pretty certain they consume less electrical energy than would be needed to run hydraulic units. Keep in mind also thatunless the motor is turning, these would have no power whereas the electric units do.

[i][/i]The only thing that needs to be done is to change the laws of physics.

Get congress to change the first and second law of thermodynamics and you're all set. It should not be too hard to find some congress men or women to sponsor that bill. They just haven't thought of it yet.

That's right up there with the move to outlaw dihydrogen-monoxide. The number of people it kills every year (in any of the three states of matter, it can be deadly) is staggering, yet nobody will lift a finger to regulate this chemical compound.

What I picture in my head is a generator with a small engine built into the trunk that could put out just enough to run the electric motors and propel the car by it'self at say 55 mph on it's own like a "limp in mode" but could charge the batteries at anything less sort of like how a diesel electric train works but with batteries. It would probably work with about a 15hp honda generator in a tesla with it's superior aromatics. It could run on regular gasoline in a pinch but could also have the batteries charged via plug in when you are sleeping, eating or at work.

An alternator isn't an on/off device, properly setup it only puts out enough to maintain system voltage. If the load only calls for 20A of charging current then that is all any alternator will put out 40A or 200A. There is an argument to be made that having a stable system voltage provides for a more consistent ignition system and a more consistent run. It would be more accurate to say the more load there is the more hp it takes to turn the alternator.

That said, the reason drag racers don't run an alternator is more for weight savings. As little as they stress the battery between rounds is what allows them to get away with it. You'll note they charge the battery between each round, or damned well better.

That is the only application I can think of that allows for running without an alternator.

Many just use an alternator cut off switch, which allows it to freewheel during the run, Probably a 1 hp drag instead of 5, course you’re still carrying the weight.

I have a copy of The Doctor's Guide to Optimizing Your Ignition System kicking around somewhere. In it he mentions a WOT switch to do similar. This way it works always at WOT and always remembers to turn the charging system back on.

As things in racing trend towards more modern technology, i.e. fuel injection, electric fans, just running off of battery isn't going to cut it.

Still running a carb and points, you're ok.

THIS, the old money thing again, Great post by AMC, I knew there were plenty of ideas out there, and plenty more to come, the paradigm shift HAS to happen and happen soon! Luckily will be long dead by the time this is all figured out, the only problem is what is going to be found out in the next 5-10 years when the realization finally hits the idiots in charge (pun intended) that pure electric vehicle power IS NOT POSSIBLE with the technology available, setting arbitrary goals is just asssssinine...

i was looking for a reason to post this

https://www.youtube.com/watch?v=wW7J2DkRaO0

it cant charge itself but WHO CARES!!!!!!!!!

A 427 with 3.55 gears can easily send that much TQ to the wheels and go twice as far on a fill up.

Hydroboost brakes for small cars are tiny. Recall the system that some Fox Body Mustangs had. Not very heavy, doesn't require a whole lot of space and I'm sure some egghead tasked with improving the design should be able to.

And yes, when the vehicle ISN'T moving, there would have to be some sort of backup pump to send enough fluid to the steering & brake unit and keep flow going with the heater circuit. No, my idea is not perfect but at least I'm trying to solve a problem with proven methods rather than creating a bunch of band-aids that create MORE problems.

But yes, I would like to sit down with somebody with more brains than I to calculate how much energy would be necessary to power a small power steering rack and a small hydroboost brake unit. I can't imagine it would be much more than an Automatic transmission pump already makes. There's always got to be some give and take. My system gives the vehicle a central, hydraulic system whereas currently; cars have 100 or more separate electric systems all trying to accomplish the same thing.

There's got to be a balance somewhere.

https://ionpowergroup.com/how-it-works-on-earth/

Most have heard about Ben Franklin (and son) flying a kite in stormy weather and seeing a spark jump from a key attached to the kite string to ground.

If you do not want to recharge your battery from either:
electric company source
local internal combustion engine generator
steam engine generator
solar cell
wind mill
hydroelectric dam
tidal flow generator

it is also possible to generate some electric power simply by having a long wire with one end up high, and the other end low and connected to ground.
Current will flow, and you can pass this current through a battery or motor.
Hint: current kinda low in typical weather unless one wire end very high up.

This also works in space,
and you may have heard about the “tether experiment” that sadly could not unspool its extremely long wire.

And here I thought this was going to be something like what an iRobot Roomba does; remember where its charging station is, heads for it and plugs itself in.

there was a commercial for an electric ford truck that had it plug into a house and appear to "power" the house.
does that mean one could plug a charger into the house while the truck was powering the house, and charge the truck at the same time ?
that commercial was on for a short while, but i haven't seen it in a long time.

Concerning adding range extenders to an EV --- GM did that with the early Chevy Volts, The EV was re-charged by a non driveline connected ICE engine. In effect the Volt had substantial range. GM discontinued the Volt because of cost added by the ICE range extender. This extender was not connected to the drive wheels - it was simply a basic generator.

They will as long as you are going down hill. I read about a guy who lived up a fairly big hill and he was having trouble with his EV since he fully charged it at night. Then the next day as he drove to work the car would overcharge itself and cause problems with the battery. He finally figured out that he only needed to charge it to 75% capacity and then it was okay heading down the hill in the morning.

My wife's mother lived up the hill from where we lived. First time my wife drove the Leaf over to her mom's house she was worried about the battery life. But by the time she got back home most of the charge had recovered. Going up hill in an EV really drains them but you get a lot of it back when you go down the other side.

I saw an article yesterday about the current (again pun intended) testing of roads that have built in charging capability, of course I didn't save it and will have to look for it again...

Someone experience in towing vehicles on trailers should start a new business along the interstates leading to and from Florida.

Have trucks with trailers and onboard generators that can haul and at the same time “Supercharge” an electric vehicle during a portion of its trip north or south.

“South of the Border” tourist trap on I-95 should start offering this service.

AAA offices near Interstate highways should start offering this service.

The customer might also want to order a meal and eat it while being hauled and charged.

That is probably a good idea. There should be enough room on a rollback to add a generator system so an EV can be charged while being being transported. That way the EV will have enough charge in it when you get to the destination that it can move under its own power.

Because if an electric car could create enough power to propel itself indefinitely you would have created perpetual motion for the first time in the history of the world. Newton says that can't be possible.

Those of us “of a certain age”
will remember Nuclear Power advocates claiming
“it will be so cheap no house will need an electric power meter”.

Less remembered are the “backyard nuclear batteries” for each house that only needed to be swapped out every 50 years.
My Thermodynamics professor had a detailed engineering drawing of such a home backyard buried nuclear battery on the wall of his office.

If you have visited older US Nuclear Power plants you have probably seen the large gravel parking lot-like areas with the large stainless steel casks containing “aged” nuclear waste still giving off heat. I was told if those were allowed to have “thermoelectric junction DC power units” inside next to the radioactive fuel elements they could generate 5 kilowatts each. Instead they just heat the outside air.

Some long life space probes have nuclear heat thermoelectric junction generators..

If each electric car had a 3 kw nuclear battery, over 24 hours of each day it could recharge its 70 kw-hr battery.
Judging from the size and weight of the space probe generators, it might add only 100 lbs or so.

The US Patent Office has granted patents on perpetual motion so it must work!

Perpetual Motion Patents

I am not asking for perpetual motion, just add a couple alternators to give extended range! Racers have been putting pulley's on driveshafts for years hanging an alternator close the the rear end, so any rotating member could be used to put on a pulley and hang an alternator somewhere...

What would that accomplish? What do you think is driving those alternators? Besides, the battery pack requires a heck of a lot more voltage than any alternator you might hang on a driveshaft, or wherever.

EV's already use regenerative braking to recoup energy to some extent. Read up on that because it sounds like you don't know what that is. At any other time the motor is driving things and all you are doing is wasting more power than you could recoup driving something to charge the batteries. Anytime energy changes state (electricity to mechanical, or mechanical to electricity) you have conversion losses. It the cost of doing the conversion. What the percentage of energy is lost is varies depending on how efficient the device is but absolutely zero of the them are 100% efficient. So you lose just in the conversions involved and you'd end up with worse mileage than you started with.

Even if you could make them 100% efficient you'd have a wash, same in as out. You'd have to be more than 100% efficient to gain anything and that's perpetual motion.

I know what regenerative braking is, known it for decades. Posts like yours just say "nothing can be done" and leaves it at that. I am asking for a paradigm shift in thinking, so what you are saying is that there is no reason to even try. ANY help keeping the batteries charged is better than just saying "it won't work"...

I didn't say nothing can be done. I said your idea can't be done successfully. Multiple people have told you it won't work, it violates the laws of physics no matter how hard you roll your eyes.

You want to do something to charge an EV while it's in use? Put solar panels on it, mind the aerodynamics. Get one of those old WWII hand crank generators and get your cardio while you are at it.

Ultimately, the only idea I have heard that might be actually functional and not pie in the sky "I don't know what I am talking about but it sure sounds good listening to me talk" thinking is a wireless charging system imbedded in the roads. No idea on cost effectiveness or charging efficiency.

I talked about the road charging earlier. I just figured there are a few smart people here on the board who might think beyond "the law of physics". Those laws only apply on this planet I am pretty sure...

One wonders where you got your engineering degree, Cracker Jack box?

There is a huge number of Neutrinos passing through us and our vehicles all the time.
That flux of Neutrinos has energy,
but since we do not even know the mass of those various “flavors” of Neutrinos
we are ignorant of even the amount of energy,
and clueless how to power something from the flux.

It gets worse,
Physics does not know if there is “Dark Matter” or “Dark Energy”
although we see behavior out in space that hints there might be.

It is not unreasonable to wonder if in the future electric vehicles can tap into presently unknown power sources.