Have you ever wanted to own an electric car? or have you ever wanted to drive a Porsche 911? I wanted both, so I decided to build one. This blog is here to document my journey as I convert a 2002 Porsche 911/996 Carrera 2 from a gas guzzler to a completely electric vehicle - not a hybrid!

Saturday, October 27, 2012

Range testing - ha

Today I drove the car around until it died.  I had to push the car into an AppleBee's parking lot.  I spoke with the manager and he allowed me to plug into a 110v outlet on the outside of the building.  Here is a picture while charging.  While I was charging, one guy came up and asked me if I was filling my car with oil. I had to laugh at that one!
So with this first test, I went 31 miles which left 20% in the pack. Thats 19kwh/31miles = 613wh/mile, which is not very good. I was hoping for something like 300wh/mile so I could go 60 miles....

The good news is I haven't fully balanced the pack yet, so that will increase the usable capacity. I also have 6 additional batteries yet to install which will add another 8kwh to the pack, which should result in an additional 11 miles of range assuming the same wh/mile numbers.


  1. On my RX-7 conversion I was hoping to see 250wh/mile but the best I have seen is 311 and the worst was about 350. However I am still driving it like a teenager. But I have lots of stuff to work on still. Your car looks great! Nice job!

  2. You have to remember that all the major companies that make electric vehicles, Tesla, Nissan, Citroen, etc. test them at unreasonably low speeds in optimal conditions. Even the new Tesla S model ranges are reported at 55 mph instead of 65 mph, which makes a great deal of difference because air resistance goes up in the third power of speed.

    Any figures you see in the media, especially for cars that haven't yet gone through EPA testing, add 50% and you get close to what they really do. 300 Wh/mi is still extremely optimistic.

  3. I drive a Leaf - it can go >85MPH, but it takes a disproportional bite out out of the battery. 45 MPH>200WHr/Mi (I've gotten to 192 Whr with careful driving); 55MPH>238WHr/Mi; 65MPH>256WHr/Mi. These numbers include regeneration (converting vehicle kinetic energy back to electricity to charge the battery). I don't drive on the freeway much, and generally hold it down to 65MPH. Most of the time, I'm using city streets at 45.

    Kurt: It looks like you've added a J1772 connector for charging - does this support charging at 240V using public chargers? I'm also interested in your motor/controller - using a DC motor with PWM? Regeneration?