Wouldn't it be easier to fit a sail?

I think it would be a waste of time, and money

1. GENNIPOD WIND GENERATOR from Aircraft Spruce

1. Turbo Alternator BPE-14 | Basic Aircraft Products ..
   

1. Wind Generators - The Fly Baby Home Page

"(the turbine adds less than 10 pounds and very little resistance)."

There's your fallacy. Read up on the laws of thermodynamics.

Energy cannot be created or destroyed, only transferred. Therefore whatever energy you can extract from any source within a moving vehicle is ALREADY in that moving vehicle. So if the energy to MOVE that vehicle comes from the EV batteries, you CANNOT possibly extract MORE energy from the movement that it is taking to provide the movement in the first place. Ergo, no matter how "light and easy" you perceive your turbine to be, it CANNOT possibly create more energy than it takes to push it through the air on the vehicle. Ergo ergo, it can ONLY be a drain on your already limited battery resources.

This in SPITE of all the whiz-bang free energy devices that are advertised on the internet as a way to suck money from wallets.

This question has been answered in depth on numerous previous threads on CR4.

Try the CR4 search function on the right hand side of the page.

Awwww... but bubble bursting is so much fun...

An admirable illustration.

A sailboat drives the boat which has low friction in water than in land. If we can design roads and tyres with very low friction as well as high efficient wind mills and also reduce wind resistance on vehicle's front portion,the efficiency should improve. Even if the EV is not moving(by battery power),wind falling on windmill should generate power.

TCMTECH, I'm a little confused.

You say an EV needs 1000 Watts mechanical and have a motor that gives 1000 Watts mechanical for 1200 Watts electrical - correct?

With the 1440 Watt Battery, you could run (theoretically) for 1.2 Hrs.

Adding another motor to run a 2nd generator is self defeating because any energy taken to run the 2nd motor is energy that cannot be used for the first motor.

To get the 1200 Watts electrical for the first motor would require (using your efficiencies for the motor and generator) 1728 Watts electrical from the battery.

Or to put it another way, paralleling the two motors would shorten your run time from 1.2 Hrs to 1440/(1200+1728) or .49 Hrs.

Basic law of thermodynamics - you can't break even

GA. You make some good accurate points.

I try and stay away from these types of blogs where the OP is not an engineer and doesn't have a clue what he is talking about, but its like Black magic, I have to see who is going to "Bump him off" first.

A fatal fascination.....

By the way, you were all far too kind up to now......he will learn nothing here, because he understands nothing at all.... What the Irish call an "Ijit"....

Wow, you must have been having a bad day!

Technically this is gibberish. I suppose you could say "Well you get what I mean, so who cares if I slaughter the grade-school physics?" I'd say the OP is probably horribly confused already, and you've just added more confusion. He is probably searching the web right now, trying to figure out how a watt is a unit of energy.

1000 watts of mechanical energy

Did you mean 1000 watt-hours of energy or 1000 watts of power?

This same error is repeated many times, so I won't highlight every one.

Here's a different flavor, though:

drawing 440 watts per hour

Was this intended to make sense? Ordinarily, a rate/time is an acceleration.

THIS was all you could find to pick at in this whole thread?

I graduated as a D- English student and I don't hide it either however even with that the last time I looked was still far from being the worst here regarding terminology, spelling, or grammar in general.

For the most part it is technically correct being I do not use time references in any of the wattage and efficency calculations which means that at any one point it could be taken directly that any device was being measured instantaneously for both volts and amps giving a instantaneous wattage value without any time reference needed.

Amps x Volts without time is just watts not watt hours.

If you look at only point do I reference time and watt hours is in regards to the battery AH and related watt hour equivalent it would have and the approximate run time it would provide the theoretical systems as a whole.

Given that I would consider it technically correct in how I was phrasing things.

You have to be tcmtech posting anonymously .......exceedingly obvious to the simplest of folk here (me!).

By the way, Admin can tell EXACTLY who it was, so think carefully before posting anything that is unfriendly, unmannerly or rude again......it's simply not needed.

Anonymous posting is not what it used to be!!!!!

I have not marked your post to be reported to Admin, but you are only a click away from having that done by myself for example. I cannot speak for others....

Apparently the definition of whats rude varies greatly from one county to the next?

K Fry got my response to his concerns in post 25.

If admin wants to leak names of who's who using the anonymous post function to the common folk here I really don't care. I am pretty sure that if a list of who's used the function and how many times was posted it would have me down at the lowest end of its list for total posts VS anon posts.

To me this is just one more reason to get rid of the ability for anyone to post anonymously here and I would happily voting to get rid of it all together.I find it rather petty and childish anyway.

Personally it would not bother me one bit either if they dropped the GA and OT voting capacity as well. I consider it pretty much just as useless anyway.

Anything else you want to accuse me of doing or not doing under any other names as well?

You were unfriendly to K.Fry.

That is not needed.

Your math was also completely off.....

Maybe it was a bad hair day?

But don't expect that we will let you get away with it.....

I am happy that admin will talk to you about it if and when needed......

But for the rest of us, it was completely obvious who posted, we did not need to have administration access for that......

You should first ask yourself why you feel you need to post anonymously.....and then not do it......

Have a great day.

There are some people on CR4 of whom I am sometimes jealous. TCMtech is not one of those people, although he often puts forth pretty good answers, when he is not being condescending.

Rather than highly anal, I am probably moderately anal -- about average for an engineer. Most engineers appear to be anal about math and using the right units, because those are the tools of our trade. If you do the math and do not have the right units, then the units won't cancel correctly, leading to stunningly wrong answers. Put "2 x 4 amp hours x 4 volts in btu" into the Google search line calculator, and you get a numerical answer. Put in "2 x 4 amp hours x 4 volts in watts" and you don't get a numerical answer. It can't figure WTF you mean.

TCM makes this sort of error many times in his post.

It is also an extremely long post that does not get the point across as well as JohnDG's post #1, which is brief, and avoids being insulting, and spells out the critical assumption (which could be different that the OP's plan) re the energy coming from the vehicles kinetic energy. If that is not the OP's plan (if the turbine is a gas turbine, for example) then John's answer remains a good answer because it spelled out the assumption.

But what prompted me to comment was really the first few words of the post: "Let's start with some grade school math..." While some people might not take that as condescending, others will. Having started off on that foot, then he better be darn sure that his "grade school physics" are correct. And they are not.

And then again, part of my motivation was humor. We all yank one another's chains periodically.

You do understand that I have for the majority of my working life dealt with the average person and their terminology and like definitions regardless of whether they are perfectly correct or just generalized close enough to get the point across to those educated enough to catch the intent?

I write as I speak for better or worse and engineering linguistic purity and form are not on my list of things to worry about when I type responses. Neither is concerning myself about who interprets what I say as good, bad, insulting, condescending, rude, humorous, sarcastic, or whatever else. At least I give the courtesy to run my posts past spell check(when it works anyway) which I see so many others don't even put forth that level of effort in their posts!

FWIW I wouldn't mind it one bit if this site gave us more than 15 minutes to do corrections to our posts. I see lots of mistakes I make when I re read what I posted some time later and it would not bother me one bit to go back and fix them either to make them more grammatically or technically correct when I see fit but I cant so everyone has to live with what and how things get written the first time around.

I will work on my terminology and scientific correctness if you will work on your admitted moderate anal tendencies!

As far as my being condescending or rude anyone who doesn't like it can bugger off!

This seems like a good enough place to cut this off, now let's play nice everyone

Y'know what they say, if you have nothing nice to say, go home and blog it instead!

A properly designed windmill will drive a vehicle into the wind, if there is a vector translation device on the vehicle. We call the wheels. Geez, guys! Have you never sailed a boat? Cars have excellent keels, very efficient.

So even a 45 degree headwind would add energy to the vehicle, which could be turned into electricity, or even, through a transmission.

What happens when you are becalmed? What makes you go then? Oars? You still have to drag the windmill along.

I'm OK with "outside the box", if it works, but let's not be ridiculous.

So, what will move the car when the wind's not blowing? Solar panels? Gravity? Steam power? Pedal power? Maybe a gas engine?

Unfortunately, conventional wisdom usually wins out over fantasy.

And how much ballast has to be in the bottom of even a small sail boat to keep it from becoming unstable and flipping over at only a few miles per hour speeds let alone 50 - 70+?

Just inagine all the cell phone yackers that will not be paying attention and properly tacking the sails and tip over.

Not to mention what happens when they meet trees, utility lines, street lights, stop lights, bridges, and any other overhead obstructions that any normal vehicle would just drive right under without a second thought!

Sail power works great in the open water environments where staying in a lane and not having to do regular stop and go or sharp corners or deal with continuing and random wind changes due to obstructions is not an issue.

Let's see. I'll assume your turbine is a gas microturbine. I'll assume your EV is a Tesla Roadster.

The Tesla's battery is 375 volts. Therefore, your 28 amp alternator (assuming you have correctly selected it to produce a little over 375 volts) will produce about 10.5 kW. So, suppose you let it run for an hour before you go for a drive. You will have put an additional 10.5 kWh into the battery pack (ignoring losses, and assuming it was low enough when you started to charge.)

Determining range addition is a no brainer: The Tesla uses about .3 kWh per mile, so you will have gained 10.5/.3: about 35 miles range.

As an alternative to a micro turbine, you could use a wind turbine.

Here is an article about a wind turbine "powered" car from China. This sort of thing does not work at all, because overcoming the additional drag of the fan requires far more power than the generator connected to the fan produces. Adding a fan like this, as shown, will reduce range, and would have a more pronounced detrimental effect if the car were already streamlined.

As you can see from the video, the fan does not turn while the car is being driven, but at high speeds it could, creating perhaps 2hp worth of drag, and (as a very generous estimate) 1hp worth of electrical output. The net loss would be 1hp. Range would be improved by removing the device from the front of the car, obviously.

The Chinese car could generate power (to charge the batteries and extend range) if it were parked facing directly into a very strong wind. Then, because the vehicle is not moving, the wind is supplying the energy (and the brakes are keeping the car from being blown back). In contrast, if the car's movement is supplying the energy, (to make an apparent wind that turns the fan, yada yada) then then energy supplying that movement comes out of the batteries, and only half that is returned (in a system that is more efficient than the Chinese car appears to be).

Obviously, a better way of extracting energy from the cars movement would be with a fifth wheel. Then you could get perhaps 80% of the additional energy expended to turn the wheel and generator back into the battery, under near perfect conditions. So range would still be reduced, but not as much. Even better from the standpoint of simplicity: Most EV's have regen braking: just alternate accelerating and braking constantly. In a near perfect car this would only reduce your range by 20%. In practice this will reduce your range by perhaps 40%.

Obviously, vehicles can be powered by the wind alone. Ice boats can do about 8 times wind speed, land yachts can go almost as fast, and even purpose-built water craft can go 3 times wind speed. Such craft, if windmill-powered, can sail directly into the wind, and directly downwind at greater that the wind speed (a feat which is not possible with a traditional sail). Windmill-powered craft have not been especially efficient, but they can do neat tricks.

Re: the Chinese car guy.

I seriously doubt he gets 90 miles out of that, there does not appear to be much in the way of batteries in that thing. Maybe 90kM, but not 90mi.

In a land where 90% of the vehicles on the road are human powered though, he has an advantage, for now anyway. Notice that in that entire video he encounters only one other vehicle, a bus. Stop-and-go traffic in a big city would kill that thing in a heartbeat. His 90kM would become 900M...

I very seriously doubt 90 miles range too. This has shown up on the web in several places with slightly different stories, and one of those stories also said that it goes 90 mph -- insanely unlikely. Elsewhere on the web it is described as being solar powered too. The solar panel appears to be about 8" x 10," meaning that given a year's time, you could gain enough charge to make it to the corner store.

I wish I spoke Chinese. It would be fun to hear the explanation.

If the windmill is mounted on top of the car,even when stationary,it will generate electricity. If it senses wind direction and align accordingly it would be ideal. If the front of the car is designed aerodynamically to get less wind resistance or as a jet allowing air in front to pass to rear of the car the range would increase.

If the windmill is mounted on top of the car,even when stationary,it will generate electricity.

Yes, provided, of course, that the wind is blowing.

If it senses wind direction and align accordingly it would be ideal.

Yes, A vertical turbine would accomplish this, as would those equipped with a tail, such as used on sailboats for auxiliary generation.

If the front of the car is designed aerodynamically to get less wind resistance or as a jet allowing air in front to pass to rear of the car the range would increase.

If the car is designed for minimum wind resistance, then adding anything like ducts to it increases that wind resistance. Can you get back an amount of energy to compensate for the additional drag? No. (Also, a small ducted fan is less efficient that a large airfoil based windmill.)

This energy loss is true even if there is a headwind into which you are driving: the headwind creates more aero drag than can be recovered by the windmill. The only reasonable way to make use of a ducted wind mill (or any windmill that does not weathervane) is when the vehicle is parked, when the apparent wind is not created by using up battery energy. It must be parked facing directly into the wind. Making this practical from an output standpoint requires a large windmill, which is then impractical to mount on a car, and costly for its output.

Typically, cars travel at speeds much greater than windspeed, meaning that (in sailing terms) the apparent wind is almost "on the nose" most of the time. This means that drag of a windmill is well-aligned to slow the car down. If windmills were more than 100% efficient than this scheme would work. But realistically, you are doing very well to get 50% efficiency, so there is a net loss in range.

In very slow city driving in a windy city, and with a vertical turbine or a weathervaning turbine, then the scheme can work*. With ducting, even the windy city scheme won't work because the ducting only works when the drag of the windmill is aligned against the vehicle's progress, in which case the windmill works to decrease range, rather than increase range.

The key is that the energy has to come from somewhere other than the car's motion (unless, as in regen braking you are trying to slow the vehicle.)
Then there are the cost issues. EV's are already expensive without adding the expense of a windmill system.

* For example, a very small car (Kei car sized) with a Savonius windmill of about 1 meter diameter and 2 meters height could fit on most city streets where trucks go. In a very windy city with very low cars speeds, the windmill could make a meaningful contribution to range. The rocking of the car by gusts might be frightening, and you'd want to go around corners very slowly. Once the car's speed gets close to wind speed the drag issues would make the scheme unworkable. Hard to find a windy city without trucks and buildings to block the wind, of course. I suppose it could be a beach novelty, although real beach buggies would be faster and more fun.

Where else can you live with very low vehicle speeds: On the water! Perhaps there is a way to use wind power to move a boat.