Wind turbine on the front of a car.

[Frank Lee]

Originally Posted by Ryland

A tilt up tower on the vehicle is going to be heavy and near useless as most vehicles are not heavy enough to keep a useful sized tower from tipping over.

Bring tent stakes/weights for the guy wires.

[jamesqf]

The bottom line is the same as with solar panels: if you have $X to invest in wind turbines, solar panels, or whatever, it's much more cost-effective to put them in a good location where they can generate whenever the wind's blowing or the sun's shining, than to put them on top of a vehicle where they have much less than optimum exposure to their power source, plus you have to burn energy to haul around the extra weight.

[Cd]

I was trying to find more info on that EV with a fan on the roof.
Google didn't help much :

[freebeard]

This is not the low profile top of a van style generator I first thought it to be, in fact the workhorse of the design is what's underneath once projected up into an air-stream.

Thanks. That's interesting in a different way. I was thinking the top part rotates and it could have cyclic pitch for the solar and collective pitch for the wind.

But this is more like Bucky Fuller's call for indoor windmills. If the PV vanes were pitched cyclically [following wind direction] and it sucked air up through the unshrouded bottom half, it would substitute for the conical rotating vent [as*] used on the 1947 Dymaxion house.

I think I like it better.

Edit:
*An indoor windmill wouldn't be appropriate for a house, it would be a little breezy. But a greenhouse could benefit from a strong breeze. A low arch dome would maximize both planting area and the lift from wind load that would translate into harvestable power.

Not a good idea to have a rotating mass on the end of a pole. Better to mount it tangent to the surface of a geodesic. The concentric rings resist the vibration.

2nd Edit: http://www.yigang-design.com/ is nothing but an inducement to install Flash™. As if.

[aerohead]

Originally Posted by jamesqf

Not so - see the link I posted. Under the right conditions, you can extract more energy from the wind that it takes to propel the vehicle. Of course that's actual wind, not relative, so it doesn't work in calm conditions. Otherwise, how's it logically different than powering a car hooked to a stationary wind turbine?

The article I looked at was about a turbine-propulsed vehicle running downwind,which would not be germane to a discussion about a turbine generator on the front of an I.C.-powered car.
*Turbines cannot have over-unity efficiencies when extracting work from a working fluid.
*Generators cannot have over-unity efficiencies when converting shaft work to electrical power.
*The theoretical maximum mechanical efficiency for a turbine is in the 80% range.
*The turbine nacelle will add drag
*The support structure which holds the turbine unit in the airstream will add drag.
*The amount of energy harvested from the turbine will always be less than the energy entering the system,or you're violating the 2nd-Law of Thermodynamics and into unicorn territory.

[Hersbird]

What if you were driving into a headwind? Theoretically couldn't you add more power then it cost from weight and drag?
Then of course you would need a big spinnaker for the other direction. We need wider roads so we can tack as well.

Actually I just watched a different blackbird video that shows the physics. I may need to eat my sarcasm
http://www.wired.com/2011/02/ff_fasterthanwind/

[jamesqf]

Originally Posted by aerohead

The article I looked at was about a turbine-propulsed vehicle running downwind,which would not be germane to a discussion about a turbine generator on the front of an I.C.-powered car.

Certainly it's germane. It is a working demonstration (and of the most extreme case) of the fact that you can extract energy from absolute wind, even in instances where "common sense" suggests you shouldn't be able to. Thus a car with a turbine generator (and it's irrelevant whether it's on the front, back, or in the middle) could in principle extract energy in excess of the drag it adds, as long as you're driving in windy conditions.

[Joris]

One of the world’s four largest sustainability races – Een van de vier grootste duurzaamheidsraces ter wereld | Every august at the Sea Dyke in Den Helder, (inter) national student teams race against the wind. The world record is 96,91%,

Not very practical for everyday use, but it seems to be possible.

[aerohead]

Originally Posted by jamesqf

Certainly it's germane. It is a working demonstration (and of the most extreme case) of the fact that you can extract energy from absolute wind, even in instances where "common sense" suggests you shouldn't be able to. Thus a car with a turbine generator (and it's irrelevant whether it's on the front, back, or in the middle) could in principle extract energy in excess of the drag it adds, as long as you're driving in windy conditions.

I went into my fluid mechanics text.I was wrong about the numbers I shared.The theoretical maximum efficiency of a wind turbine is 59.3%.
The text reported that in actual practice,the efficiency rarely exceeds 40%.
Wind is free,so there's an engineering 'disconnect' with respect to 'fuel cost',and fuel economy'.
When the automobile's engine must create all the 'wind energy' for the turbine to extract it's portion ,we run smack dab into the 2nd Law of Thermo.
There are sail effects associated with automobiles,given certain relative wind spectra.It's been known about since around the 1920s.But it occurs at very low driving speeds.Lower than motorists would put up with.And we have no control over wind speed and direction.
And as far as I know,contemporary wind turbines simply orient their turbine blades into the wind.
Reaction turbines have exotic,streamlined stator turning vanes to guide the flow onto the turbine blades.
The larger the turbine,the more efficient,due to the relative leakage proportion around the blades.A small,ducted,'internal' turbo-generator would suffer this inefficiency.
If you've got some peer-reviewed scientific paper which illustrates how we go from 59.3%,to 100+% efficiency with a turbine electric generator 'd love to see that.

[aerohead]

Originally Posted by Joris

One of the world’s four largest sustainability races – Een van de vier grootste duurzaamheidsraces ter wereld | Every august at the Sea Dyke in Den Helder, (inter) national student teams race against the wind. The world record is 96,91%,

Not very practical for everyday use, but it seems to be possible.

If the Montreal team's Chinook ETS was racing into a 5.5 m/s wind,we're talking 11.7 mph for the car.