From Guest Blogger Writer MC: Classic Car to Electric Car–an Easy Experiment
I loved my 1972 VW Beetle. It was the car my mom bought when I was a baby, and I spent many childhood hours riding in it and, when my parents replaced it, playing in, on, and around it. When I learned to drive, it became my first car. It was the car I drove my girlfriends around in and even the one who would become my wife (though her parents imposed the ridiculous stipulation that I replace the passenger side seatbelt first). I drove friends around in it, and we acquired dozens of great stories from it, (like how one of them sat down too hard over the battery and got a shock that burned through his shorts). I had beaten up, abused, and loved that car for decades so that it had become real, like the Velveteen Rabbit.
But there was a problem. I had beaten up that car too much, and now it was very unreliable. In the last decade of its life, it had been towed more miles than it had been driven. It was intermittently out of service, and even when it was running it was inefficient, getting an unconscionable 20 mpg. It only passed its emissions test because neither I nor the lax inspector noticed that the tailpipes weren’t properly connected to the muffler. I tried to tune it, but it was beyond me, and I was realizing that getting it in proper condition was likely to cost a lot. Facing the prospect of putting money into the car anyway, I decided to convert it to an electric car. (A decision that alarmed my friend who had been burned by the battery in the past.)
To Kit or Not to Kit?
It used to be that EV conversions were a pioneering effort. Every conversion was completely new, so you had to do a lot of experimenting. These days, there are good conversion kits available that make it easy to convert some vehicles (such as a VW). I started out thinking I was going to start from scratch to convert my Beetle, and bought this excellent book on the subject, but I soon figured out that to do that I would need to have access to a machine shop to custom-fabricate some of the elements. Then I thought I might purchase some of those components and assemble the rest together myself. In the end, though, I decided to purchase a kit.
There are a lot of places out there you can buy kits from these days, but I got mine from Wilderness EV. It included everything I needed except batteries, and I was very happy with almost everything included. Especially important is the #2/0 cable that it included was the very flexible welder cable that is much better than the #2/0 I could get at my local hardware store. You will often have to thread the cable through some tight places, and it’s hard enough with the flexible cable–it might very well be impossible with the more rigid cable.
The only component I was disappointed in was the battery cable terminals, which are the standard automotive ones. It may partly have been my installation, but these proved to be insufficient for the purpose and I had a couple of these melt on me once (and take the batteries they were attached to with them). I have since replaced these with aluminum screw-on terminals that work much better.
Another caveat to the Wilderness EV kit: it comes with a basic series DC motor. This isn’t as efficient as an AC motor and it isn’t compatible with regenerative braking (if you want to try to get all fancy).
A kit comes with straightforward instructions, making it very easy to install. There are some challenges to getting everything in place, but once it was done, it worked great on the first try (except for the fact that I hadn’t bolted one of the wheels back on properly, which had nothing to do with the conversion).
A Change for the Batteries
Batteries are one of the most important decisions you will have to make about your electric car. They will determine your range and performance (and, to a great extent, the cost) of your converted car. Standard deep cycle lead acid batteries (most commonly described as marine batteries) are the easiest and cheapest to obtain. The ones you can get at your local battery store can work just fine.
In selecting batteries, you need to worry about amp-hours (Ah) and volts (V). Basically, volts will determine your speed and amp-hours will determine your range. (Here’s a more in-depth discussion of amps and volts.) Your engine will tell you how many volts it needs, and you can wire batteries together to achieve the proper number of volts.
You can also buy batteries that are more specifically designed for use in electric vehicles. These batteries are significantly more expensive, but might give you better performance. Another limit on the batteries you get is where you can fit them. In my VW conversion, I put half the batteries in the trunk and half of them in the little cargo area behind the back seat compartment. (In consideration of my friend, I didn’t put any of the batteries underneath the back seat.)
You will also have to figure out how you want to run the low-voltage system for the car’s built-in components like headlights, turn signals, and all the rest. You can either use a DC-DC converter that will run the power using the main batteries, or use a secondary 12-volt battery. A DC-DC converter is expensive, and it’s important to buy one that can handle the full power demands of your car’s system. A secondary battery is cheap, but requires a second charger.
What’s the Cost?
Actually, this is the amazing part: it’s not very expensive. The conversion kits from Wilderness EV run in the $2000-5000 range, but don’t include batteries. Lead-acid batteries start around $100 apiece for 12V 100-Ah, but they can easily be twice that or more for more premium styles. I went with very cheap batteries and ended up with a total conversion cost of around $6000, but I’ve seen kits that include higher-end batteries marketed for $18,000 (and the cost of Tesla’s battery pack alone is about $30,000). When it comes to batteries you get what you pay for. My basic conversion has a range of about 25-30 miles a charge, and the higher-end conversion kit promises a range of around 80-90 miles (while the Tesla S can get more than 300 miles on a charge).
It’s also important to account for rebates and incentives at the federal, state, and local level. When I did my conversion, I knew there was a federal incentive that would refund more than $1000 of the cost, but I didn’t know about a state refund that went above and beyond that, paying up to 85% of the conversion cost, so my net cost was actually less than $1000. If I had known about the state-level incentive, I would have invested in better batteries, but instead we took the refund and made it our down payment on solar panels, and put better batteries on the wish list for the future, when hopefully prices will have come down.
