Senior Member
Joined: 04/01/2008
Location: AlbaniaPosts: 510
| Posted: 06:26pm 12 Dec 2008 |
Oz, have you considered expanding from cars to, let's say, farm equipment? I bet there's a market for electric flying combines too. I know of at least one potential customer.
[quote=Oztules]Strange thing is everyone who has seen it hooked up to the windmill, then taken it for a drive loves it...... which is pretty strange as it looks like a pile of the proverbial. No accounting for taste over here apparently.[/quote]
I'm not surprized at all people like it, Oztules. But maybe that says a lot about my taste too... Pity the car was in such a bad condition; with just a hood, windows and doors it would have been a perfectly serviceable electric car.
[quote=Oztules]no oil, water or petrol.[/quote]
But sooner or later you'll have to top off the batteries with water...
What capacity is your battery bank (nominally vs. actually)? The voltage was 36V IIRC. Presumably the batteries have already seen a long useful life in some other application and were then given to you to spend their final remaining days before inescapable death? Would be interesting to measure batterycapacity; that way you could also estimate the range (and re-charge periods) when installing fresh new batteries.
The motor is rated at 4kW so about 5.5hp. There are lawnmowers with more powerful motors than that
. But if you don't require fast acceleration, who needs lots of power. As long as you have enough power to overcome hills and pull free out of the mud/grass. Anything more is just unused capacity 99.9% of the time and extra dead weight. Would be very interesting to find out what the maximum range on decent asphalt roads would be. Endurance may well be double of what you get on your property. As for speed... who cares anyway. Anything that's faster than walking is good.
As you mentioned, it all comes down to weight. In your case, with relatively low speeds, aerodynamic resistance will be smaller than tyre fricion. At normal car speeds and on normal roads, aerodynamic friction would dominate the total drag. But since your car drives slowly and on non-smooth paths... Anything that can be done to reduce weight and reduce tyre friction would further improve performance. I notice there's still some dead weight on that Suzuki in the form of a passenger door and roof.
A human weighs about 70kg on average. A full-sized car (well, ok, my tiny car) is ~800 kg. Which means only about 9% of transported mass is actually 'useful'. If you could change that ratio to, say 25% (tiny car frame, motor and batteries comprising most of the mass) you'd have made a huge gain in endurance and efficiency. Considering that your Suzuki is little more than some sheetmetal, 4 tyres, a motor and a battery... you're getting pretty close to the ideal. The Apollo moon-rover comes even closer though: 4 wheels and a frame. But then, they had to haul it all the way up to the moon too.
A golf-car comes pretty close to that ideal too.
Finally: I notice a loitering dog in your pictures. Have you considered giving it a harness and testing its skills as sledge dog, pulling the Suzuki? If it worked for Santa...
Peter.