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Electric Vehicle Kits for the Masses?
Aciel asks: "I just finished watching 'Who Killed the Electric Car', and was quite impressed. I'm too poor to buy anything but an old clunker, and not eager to pollute the atmosphere (or empty my wallet) with gasoline. The movie inspired me: I think I'd like to convert an old car (or perhaps a motorbike) to run on electricity. Have Slashdot readers attempted such a thing before? What experiences have you had, and what would you recommend or not recommend?"
Check out http://www.austinev.org/evalbum/ for over 800 examples of electric cars, most of which are conversions or kit built.
"Do what you can, with what you have, where you are."
This is true except it is not a good analogy- it would be true if the power plant required the same quantity of fuel and released the same by-products as a car engine to generate the same amount of power. This is not the case. Power plants are FAR more efficient, as I recall it uses about 10% the fuel if not less to generate the same amount of power.
Remember, power companies have a (somewhat) vested interest in making their plants efficient, because they pay for fuel and get political flak for polluting. They are also willing to spend far more $/KW of output than a car buyer is. Car companies don't buy the fuel, so as long as it's decently efficient and not too bad on the air they sell it.
If you flip that around, and make people willing to spend $$ on hyper efficient cars, all the cars would have gas turbine engines, perhaps in some sort of electric hybrid mode. They'd cost $80k for a Honda, but they'd get awesome gas mileage.
--IronHelix
Amplifier? I guess you mean a "Variable frequency drive".r ivee rview.htm
;-)
http://en.wikipedia.org/wiki/Variable_Frequency_D
AFAIK this is the state of the art for electric cars. Digging something up on Google...
Unfortunately, I could not find a system made specifically for cars on the quick. But for an example of a complete VFD, the following should give you a rough idea of prize, size and weight:
http://www.joliettech.com/abb_acs-550_ac_drive_ov
Note that the ABB ACS550 AC is somewhat different from what you want in a car. It takes power from a 3-phase AC line, so it will have a rectifier and some big buffer capacitor that would be unnecessary in a car system where you draw DC from the battery. OTOH, you might want energy recovery when braking, which is not specified for the above and would probably cost extra.
I'll leave the search for motors and batteries to someone else
C - the footgun of programming languages
You might take a look at some of the used ones they have: http://www.zapworld.com/cars/salecars.asp
But they do sell a bunch of $1500 electric mopeds, if you're interested in going that route.
There are some other vehicles out there, too -- you'll have to look for them, though. Some are only in development, like the x-cycle, while others are incredibly expensive, like the Sparrow.
Here's my suggestion.
I'm going to assume that you can get under the hood of a car, remove the engine, and essentially work on a car without killing yourself.
In that case, you probably want to get a street-legal old vw-bug or Ford Fiesta (or Yugo)... anyhow, something that is small and aerodynamic, and then convert it to electric with a $3000 conversion kit from e-volks. (They also have a $1500 conversion kit, but I'd go with the better one if I were you.) This is Wilderness Energy (which sells hub bicycle conversion kits, unfortunately also of Chinese manufacture and easily broken) expanded to automobiles.
Just... I'd go ahead and make the electric supply/recharge system separate from the vehicle, for the reason that you'll want to change it over later as you get more money.
Initially, you'll want Sealed-Lead-Acid batteries as can be had from Wal-Mart in the Bike section. They're cheap but heavy, and you string up enough of them to get whatever distance and speed you need.
But later, you'll want to convert to Lithium-ion phosphate, since it is lightweight, extremely efficient, long lasting, and doesn't blow up like a DELL.
Two sources for those are A123 and Valence.
Correct Horse Battery Staple: 72 bits of entropy. Enter "Correct H" into google. When it generates the phrase, that's
From the article found here, in California (which has generally pretty clean power plants), "Over the course of 100,000 miles, CO2 emissions from EVs are projected to be 10 tons versus 35 tons for ICE vehicles". Even on the East Coast, which has much dirtier plants, "EVs in the Northeast would reduce CO emissions by 99.8 percent, volatile organic compounds (VOC) by 90 percent, NOx by 80 percent, and CO2 by as much as 60 percent".
One interesting comparison in the article takes power line inefficiences into account, starts with raw BTUs from the carbon product used for power generation and comes up with an equivalent "69 MPG" for a pure EV. So, you'd have to get an ICE up to 69 MPG (average!) to match it. Note that you cannot directly compare the "200 MPG" of plugin hybrids to this number, since "200 MPG" does not include the petroleum/coal used to generate the power.
A little bit of electricity? Just so you know, air compressors are not very efficient devices. They waste a lot of heat. If you want to store 2 kWh of energy as compressed air, you'll need to use maybe 10 kWh of electricity to compress it. Second, compressed air takes has extremely low energy density. A small shop air compressor (compressing to about 150psi) usually has a 10-20 gal tank just to store enough air to run something like an air drill for a minute or two. This is for a tank made of very thick steel. Even if you increased the pressure in the tank 100 times (which is completely impossible from an engineering viewpoint) it would still not have nearly enough energy to power a car (although you could run a drill for an hour). Not to mention, a compressor that can dump a few hundred kWh into a tank even overnight would take up more space than the car and would be loud enough to hear from a mile away. You'd need like a 100hp compressor, those generally take up a large room. Here is a picture of one.
Not to mention, running a car on compressed air is pretty simple, provided you have a source of compressed air. You could even use a regular gas engine without any modifications -- simply force high pressure air into the intake. The reason nobody does it is because doing so would require an ungodly amount of compressed air. There's not much you can do to improve the efficiency, either.
My conclusion: the site is a scam, attempting to extract money from dumb investors. Note how they are focusing on silly things like the benefits of not using gas (obvious) and how they will arrange the seatbelts (irrelevant) while thoroughly avoiding any description of the actual technology. Their tanks are supposedly good to 300 bar (~4300 psi), which is realistic (that's what scuba tanks or CNG tanks are rated for). However, this is not nearly enough energy to power a car. Hell, it's barely enough energy to power a car if you store NATURAL GAS in the tanks and BURN IT.
300 bar = 30 MPa = 30 MJoules / m^3 = 8.3 kWh/m^3. If you somehow managed to put 3 cubic meters of air tanks on that thing (that's about 800 gallons -- a HUGE air tank), you would have as much energy as ONE gallon of gas. To compress that air, you would use up several times that amount, because going from atmospheric pressure to 4500 psi will release a ton of waste heat. You would also never be able to get that energy out in any reasonable length of time because the air will become very, very cold when it expands.
If that technology really worked, we would have had air-powered cars 150 years ago -- it's a steam engine that's hooked up to an air tank instead of a boiler. The problem is, there is no way it could possibly work.
Nobody's actually spraying oil on the ground (that I know of!) But the reactions that produce it are energy-consuming and require fossil fuel as reagents. e.g. Haber-Bosch process.
Electric bicycles are, IMHO, more ready for prime time than electric cars.
I commute on an EGo (www.egovehicles.com) 17 miles each way.
Conversion kits for road bikes such as your 18-speed are easy to find online.
Checking google, I see ZapWorld.com among others.
You won't go 30 miles an hour uphill, though.
15-18 MPH on the flat would be good for a conversion kit.
Electric motors have high torque, so you'll not slow down much up hills.
Before getting something fast, like your desired 30 MPH, check licensing laws in your area.