>> ^Sniper007:

Two 30 minute test drives would definitively demonstrate the case either way. One trip without the fan operating. One trip with the fan operating. Which method leaves the batteries with more juice (or goes farther before dying, etc).
It's so remedial a solution, you have to believe he's done it.


It's not as easy as that. Measuring how 'full' a battery is has never been managed to a sufficiently accurate level to compare. Better would be to equip the car with several volt-meters and ammeters, recording the input and output of electricity.

>> ^Barbar:

The point I was making was that if air passes through the turbine, (I am assuming) it leaves with a portion of the turbine's forward velocity imparted upon it. If this is the case, then doesn't it mean that the car's chassis, following directly behind the turbine will experience less drag, since the relative wind speed is lower?


You'd have to do extensive wind tunnel testing, but I suspect the turbulent air following the fan's passage would actually make the rest of the car drag more. Look at properly done wind tunnel testing, it's all about smooth flow, the most aerodynamic model is the one with the least eddies in the wind. In this model you propose there are tons of eddies and unpredictable wind currents before you even begin to introduce the body of the car.

If you could somehow design something that worked as you propose (which I doubt is possible, but it might be if you threw enough money at the problem), the infinitesimal gain would almost certainly be lost through the inefficiencies introduced by the necessary (for safety) fan shroud, and the generator itself.

First case is simply wrong. Wind generators are turbulence generators, period. If they don't generate drag they don't work.

As for the second case it would be far more efficient to simply have the electric motor work in reverse so that it uses the car's momentum to generate electricity AND braking power. No need for fancy extra gadgets that would cost tens of thousands per unit and would never be more efficient than a simple system converting momentum to energy through the drivetrain.

>> ^zeoverlord:

sure it is, first case would be if it's used to correct turbulent air that would otherwise cause extra drag, in such a case it would have a double effect, both by reducing drag and generating power.
Second case would be if you had a turbine with deployable blades that extend every time you brake, sure the gain would be small, but it is a gain non the less.
Though clearly this car does not use either of these, and the only way this would add energy instead of wasting it was if he lived in a really windy place.
>> ^Drachen_Jager:
It is impossible to build a wind turbine generator on a car that increases efficiency through wind generated by the vehicle's own travel.

sure it is, first case would be if it's used to correct turbulent air that would otherwise cause extra drag, in such a case it would have a double effect, both by reducing drag and generating power.
Second case would be if you had a turbine with deployable blades that extend every time you brake, sure the gain would be small, but it is a gain non the less.

Though clearly this car does not use either of these, and the only way this would add energy instead of wasting it was if he lived in a really windy place.
>> ^Drachen_Jager:

It is impossible to build a wind turbine generator on a car that increases efficiency through wind generated by the vehicle's own travel.

Your video, Chinese Farmer Creates Wind-Powered Car, has made it into the Top 15 New Videos listing. Congratulations on your achievement. For your contribution you have been awarded 1 Power Point.

>> ^AeroMechanical:

Maybe we'll pass by each other in the hallways while you're on your way to your reading comprehension class.
>> ^Stormsinger:
>> ^AeroMechanical:
I would guess he would find better efficiency by reducing drag. That big fan on the front is definitely not reducing drag. However, since it isn't increasing the frontal area of the car, its effect on drag probably isn't massive. Of course, then taking into account the extra mass of the fan itself and the generation hardware, I would be willing to bet that it results in a significant net loss in efficiency.
Additional: I gotta say, I do find it really odd that he would have the skills necessary to build the thing, but not the common sense to see its obvious flaw.

It's effect is to increase the drag by exactly as much as the energy the generator produces, plus enough more to offset the inefficiencies of said fan and generator.
You -cannot- gain efficiency this way, that's basic physics. If you disagree, I suggest you head back to high school for a refresher.


Sorry, I guess I wasn't clear. I wasn't disagreeing with anything -you- said except to change "willing to bet" into "absolutely certain". All the physics-challenges posts previously got my frustration levels up, and demanded a response. Yours was one of the few reasonable starting points (as opposed to the utterly uninformed majority).


Most of those earlier posts had a knowledge of physics similar to thinking that mounting a fan blowing on the sail of a sailboat would make it move. Quoting that sort of thinking is giving it too much credit.

Maybe we'll pass by each other in the hallways while you're on your way to your reading comprehension class.

>> ^Stormsinger:

>> ^AeroMechanical:
I would guess he would find better efficiency by reducing drag. That big fan on the front is definitely not reducing drag. However, since it isn't increasing the frontal area of the car, its effect on drag probably isn't massive. Of course, then taking into account the extra mass of the fan itself and the generation hardware, I would be willing to bet that it results in a significant net loss in efficiency.
Additional: I gotta say, I do find it really odd that he would have the skills necessary to build the thing, but not the common sense to see its obvious flaw.

It's effect is to increase the drag by exactly as much as the energy the generator produces, plus enough more to offset the inefficiencies of said fan and generator.

You -cannot- gain efficiency this way, that's basic physics. If you disagree, I suggest you head back to high school for a refresher.

>> ^bobknight33:

Capitalism at work in China. 1 inverter living his dream.

Socialism at work in America. In America our government forces GM to produce the Chevy Volt. Very little people buy them since they cost $100,000. The buyer pays $40K and the Tax payer eats the $60K.


"Capitalism at work in China. 1 inverter conman living his dream."

Fixed that for ya.

This is just another perpetual motion machine. You cannot violate the second law of thermodynamics, which would be required for this to work.

>> ^jqpublick:

I think it's more likely that this system extends the drive time of whatever battery cells he has installed in the thing. It's not that he's getting free energy, it's just that at 40 the system is going fast enough that even though there's a net loss, the additional energy stored in the batteries gives a longer running time. I think that's just about all that there is here.
>> ^rkone:
>> ^Drachen_Jager:
That is the dumbest thing I've ever seen.

Agreed. I'd downvote the video if I could. People, if you're in doubt, think of it this way - if the fan could generate more power than the loss of pushing it, then you could just keep adding more fans until it becomes a perpetual motion machine..



Problem, nothing happens at 40 miles an hour in physics for a decrease wind resistance and drag. If anything, the faster you go, the more of a problem wind becomes. There is no possible way that this is extending his drive time. This is exactly equal to holding your hand out the window. If you could turn that blockage into electricity, it will always be less energy than the amount of momentum it sapped via drag. Or else ALL CARS WOULD ALREADY DO THIS! The reason you don't is because it doesn't work.

A simple instance where something like this IS used is the emergency ram air turbine for jumbo jets. When there is a complete loss of power, a ram air turbine drops down to generate emergency power for the hydraulic systems. This increases drag, but it is so small that it isn't a problem. But it is also why air planes don't have windmills on them, anything you use to block the wind is slowing you down more than any recoverable amount of energy via electric conservation of kinetic energy. This is physics 101, entropy, it's a bitch!

Now, if he compressed the incoming air, added a combustion chamber with kerosene or gasoline, then he would have himself a turbine engine for his car, but now, he just has a lesson in why physics is hard.

I think it's more likely that this system extends the drive time of whatever battery cells he has installed in the thing. It's not that he's getting free energy, it's just that at 40 the system is going fast enough that even though there's a net loss, the additional energy stored in the batteries gives a longer running time. I think that's just about all that there is here.

>> ^rkone:

>> ^Drachen_Jager:
That is the dumbest thing I've ever seen.


Agreed. I'd downvote the video if I could. People, if you're in doubt, think of it this way - if the fan could generate more power than the loss of pushing it, then you could just keep adding more fans until it becomes a perpetual motion machine..

>> ^AeroMechanical:

I would guess he would find better efficiency by reducing drag. That big fan on the front is definitely not reducing drag. However, since it isn't increasing the frontal area of the car, its effect on drag probably isn't massive. Of course, then taking into account the extra mass of the fan itself and the generation hardware, I would be willing to bet that it results in a significant net loss in efficiency.
Additional: I gotta say, I do find it really odd that he would have the skills necessary to build the thing, but not the common sense to see its obvious flaw.

It's effect is to increase the drag by exactly as much as the energy the generator produces, plus enough more to offset the inefficiencies of said fan and generator.


You -cannot- gain efficiency this way, that's basic physics. If you disagree, I suggest you head back to high school for a refresher.

>> ^Drachen_Jager:

That is the dumbest thing I've ever seen.



Agreed. I'd downvote the video if I could. People, if you're in doubt, think of it this way - if the fan could generate more power than the loss of pushing it, then you could just keep adding more fans until it becomes a perpetual motion machine..

Always pointing out problems and hidden agendas. Never any solutions or objective observations.

Like everyone else, I see the world a certain way. It seems like I'm always argumentative and sometimes it's true, but if you're standing on a cliff's edge wearing wings carved from a styrofoam beer cooler and I say, 'I see the wings, but gravity will not go easier on you if you leap' am I "trolling"? Methinks NOT.

Others here said what I said in a different way: wind power is great in the rare places it can be harnessed, but overall the cost is too high for the output.

I can't please everyone, but know that it's nothing personal. My shins get kicked all the time around here. Expand your love to include love-to-hate


>> ^GenjiKilpatrick:

@quantumushroom
Neither, I just can't stand the fact that you talk out your ass all the time.
Always pointing out problems and hidden agendas. Never any solutions or objective observations.
I'll grant that your puns can be pretty humorous tho.
[when not filled with blind prejudice and hate]

I'm just going to assume you're either passionate about wind power or just didn't like my unique brand of humor, powered by coal.



>> ^GenjiKilpatrick:

Wow, QM. I didn't know you had that many monitors.
"One 1.8 MW wind turbine at a reasonable site would produce over 4,700,000 kWh of electricity each year, enough to meet the annual needs of over 1,000 households."
(the average household in the UK, with 2 parents and 2 children, uses approximately 5500 kWh of energy per year. -Strathclyde University statistic)
>> ^quantumushroom:
I like those pinwheels at the end, but together they could power the 3000 monitors I watched this sift on.

>> ^renatojj:

The usual excuse for space exploration being done by government is because the costs involved are too high.
However, doesn't the private sector tend to increase quality and lower costs with time? Maybe if we let the private sector grow and develop the necessary technologies, space exploration won't be as costly. Sure, it might take a lot more time, but at least it won't waste as much resources.
Right now, we don't have resources in the private or public sectors for this. Newt is a dumbass.


Private sector business can't take risks this big. They are responsible for ensuring profitability and you cannot ensure profitability in a venture like space exploration. Central government doesn't have the profit mandate and so they can invest in things that stimulate paradigm shifts in technology and industry.

An example; I worked for my local utility company several years back (recently privatized at the time). Wind energy was a big thing and they company was very active in promoting their wind energy program. But the truth that I found was they had actually spent more money on trying to push laws to seal government gathered data that would be necessary for the wind industry to grow. You see, they didn't want to develop wind energy just yet because the profit margin was too small but they also didn't want any energy startups who were willing to accept the thinner profit margins to get a leg up on them. Nearly a decade later and that large energy company still hasn't developed their wind power any further. And there haven't been any major challengers in the market....wonder why.

The largest industries are controlled by the largest corporations and these corporations are in the business of protecting their existing revenue streams. Innovation and exploration involve risk and corporations are risk averse by their very design. Private industry is not the machine that will push boundaries and stimulate technological paradigm shifts. That takes a large entity with no profit mandate. That takes a central government.

If you believe that profitability is the best measure of value and efficiency then you haven't thought really hard on the matter. A functioning and successful society requires a balance between capital driven entities and entities who measure their success in terms of the health and advancement of the community. This isn't a matter of capitalism versus socialism. It's contrasting motivations that work in synergy.