Electric conversion: Project ForkenSwiift

[skewbe]

Very cool, can't wait for some real world stats (0-30 times, top speed, range, etc).

So where is the garage entry already?

P.S. what is downshifting like without a clutch (spinning the motor up on the synchros?) or do you not do much shifting or hows that work?

[MetroMPG]

Right... garage entry! I should get on that.

What formula will I use for MPG equivalent though? There are 33,557 watt hours in a gallon of gas, and the FS pack theoretically (when new) holds 48v*220AH (I think) = 10,560 watt hours (less than 1/3 of a gallon of gas, equivalent energy!)

Problem is, I don't have a killawatt meter, so I don't know exactly how much I'm putting back into the pack when I recharge. Suggestions? I can estimate SOC from pack voltage... but that's kind of like estimating MPG based on where you gas gauge was before topping up.

[MetroMPG]

Whoops missed this:

Originally Posted by skewbe

P.S. what is downshifting like without a clutch (spinning the motor up on the synchros?) or do you not do much shifting or hows that work?

[skewbe]

I gotcha on the shifting.

re monitoring efficiency: I had this whole DIY Kill-a-Watt thing typed out, then went to ebay and searched for "Kill A Watt" and the dang things are $22 shipped, LOL. 15 amps max, don't know what a car charger needs.

[MetroMPG]

Hrm. One of the chargers is 20A, the other is 5A. So if I feel like waiting 24h to recharge the car using the 5A unit, I could measure it.

EDIT: wait a minute... it charges at 20A DC. 110v AC amperage will be less.

I should get a killawatt anyway...

[SVOboy]

Get it, sucka!

[MetroMPG]

Otay, Panky!

[trebuchet03]

Originally Posted by MetroMPG

Right... garage entry! I should get on that.

What formula will I use for MPG equivalent though? There are 33,557 watt hours in a gallon of gas, and the FS pack theoretically (when new) holds 48v*220AH (I think) = 10,560 watt hours (less than 1/3 of a gallon of gas, equivalent energy!)

Problem is, I don't have a killawatt meter, so I don't know exactly how much I'm putting back into the pack when I recharge. Suggestions? I can estimate SOC from pack voltage... but that's kind of like estimating MPG based on where you gas gauge was before topping up.

If you don't have a killawatt or other way to measure current draw.... Turn off/unplug everything in your house except for your charger and check out the power meter -- measure how much power it's using....

Hrmm... that only works if you know how long the charger is running....
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Do those cheap multimeters do AC current for any appreciable current?

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As for gas equivalent....see if you can figure out how wrightspeed calculated the equivalent mpg - his EV gets 170mpg eq.
http://www.wrightspeed.com/

Doing a google search yields all sorts of results.... Some are based on energy content, others are on emissions equivalent...

From the wiki entry on battery EV's -- but that section is tagged as not having a source

BEV operating costs can be directly compared to the equivalent operating costs of a gasoline-powered vehicle. A gallon of gasoline contains about 36.4 kWh of energy. To calculate the cost of the electrical equivalent of a gallon of gasoline, multiply the utility cost per kWh by 36.4. To calculate the equivalent mileage of a BEV, divide 36.4 kWh/gal by the energy efficiency in kWh/mile, to get the equivalent miles per gallon. For example, if a BEV owner's electricity rate is $0.10 per kWh, and the BEV gets 0.20 kWh/mile, then the owner is paying the equivalent of $3.64 per gallon of gasoline, and getting the equivalent of 182 miles per gallon.

Yet again, another post that looks like I'm playing darts... I'm all over the place

[rh77]

Congrats! ...really glad to hear that it worked out.

RH77

[MetroMPG]

Thanks, Rick!

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