Ken Adelman's tzero electric sports car
Ken Adelman's all-electric Tzero lined up to race Lamborghini Diablo sportscar.

California's Solar Warrior: Defying Diablo

Part one of a multi-part interview with California entrepreneur and EV advocate

By Josh Landess

Ken Adelman is a successful California entrepreneur who owns four EVs and a 30kW solar charging station to power them. His web site is www.solarwarrior.com

Owning Tzero Number Two

EVW: I'm not very familiar with the AC Propulsion Electric Car [tzero] you're driving. That isn't even out yet officially or it's coming out?

KA: Not out officially. The car we have is a prototype. It's the second car they built.

EVW: Have you been giving them the feedback on making it better or worse?

KA: Yeah, little things. We purchased it as a used car so it had been driven extensively, about 15,000 miles on it prior to us taking delivery of it. And they, during those 15,000 miles, learned much more than I ever learned about it. So in a sense they were there own best feedback.

EVW: How many more miles do you think you'll get before you have to replace the batteries?

KA: Zero. They were pretty much worn out when I got the car. Part of the purchase deal was that they would replace the battery pack with a new one. They were going to do it prior to delivery, but I decided to keep using the existing batteries and take them up on the replacement offer later.

EVW: They said something on their web site about the vehicle being around the price of a very expensive sports car. Do you happen to know anything about their plans?

KA: Well, we were in line for the third production car, but ended up purchasing one of the prototypes. Right now I think the company is trying to find a niche in a rapidly-changing market. They want to be a drive-train supplier to other manufactures as much as they want to build electric vehicles like the tzero. The cost-harsh reality of building a vehicle like the tzero is that a substantial investment would be needed to certify it, and certification would would cause a number of changes, including changes to the body style to accommodate things like headlight height requirement.

Defying and Defeating Lamborghini Diablo...Repeatedly

[Author's note: Street Racing is a big source of preventable death in the US. It is a nasty unsafe practice and I don't condone it. The questions here should not be interpreted as encouraging unlawful driving. The drag races mentioned against the Lamborghini took place on a closed course, the only appropriate venue for such contests.]

EVW: Do you have any good stories to tell us about driving one of the sportier cars and smoking a guy who thought he was driving a fast car?

KA: Oh I do that in the EV1's all the time. People look at it and say it's an electric car, it must be slow.

EVW: Get any really interesting looks on their faces when you leave them there?

KA: Yeah well I usually stop at the next light to let them pull up and discuss it.

EVW: That's mighty polite of you.

KA: Now with the tzero, people don't always realize it's electric but because it looks fast people expect it to be fast. But it's so much faster than that.

EVW: Yeah I was looking at the numbers you were publishing. I would feel comfortable going up against a fast car in that thing.

KA: Alec Proudfoot is doing a documentary on electric vehicles...There was a drag race at Moffet Field between a number of different sports cars and the tzero. Where the tzero won pretty reliably. There was no good video footage shot and he wanted to do a recreation. He had a number of different sports cars lined up but for various reasons they all fell through except the Lamborghini Diablo.

EVW: Oh no. That's a pretty formidable opponent to risk such a recreation on.

KA: Well we won every heat except the one where the driver of the tzero, who incidentally was Tom Gage, President of AC Propulsion... put it in reverse by accident instead of forward.

EVW: Yeah, I don't want to make that mistake against a Diablo.

KA: The interesting thing about the Diablo, you know they say the 0-60 time as measured by Road and Track is better than the 0-60 time on the tzero. Okay put that aside, the problem is that when Lamborghini gives the car to Road and Track and says, you know, have fun with it, they actually want Road and Track to abuse the car. Cause they want the good number, they want the engine to be revved up to the red line and the clutch dropped every time.

In this case the Diablo was not driven by it's owner, but by an experienced Ferrari driver who took some time to go out and get used to the clutch but was not willing to drop the clutch. He was not willing to give the car some serious abuse. Now we did note that the car went in to have its clutch replaced four weeks later.

EVW: ...chuckle...

KA: It was an opportunity once or twice where you smelled what could have been clutch. But it still couldn't beat the tzero under those circumstances.

EVW: Does the tzero not have any abuse concerns because of the way its transmission is put together?

KA: Well there's no friction device that's involved in coming off the line. It's just a gearbox so it doesn't suffer the stress as a friction device like the clutch.

EVW: So you're just stepping on the gas and that's it.

KA: Well actually that's not the quickest way to accelerate. It's to hold the brake, step on the accelerator and give it a second or two for the magnetic field to build to full strength and then release the brake. But it's not a complex maneuver; it's one that any teenager can master. Whereas driving the Diablo required quite a bit of skill.

EVW: Did you guys do any testing for top speed or say real world, 50 mph to 80 mph times, that sort of thing? That's the one that's always relevant to my own driving, those middle acceleration figures.

KA: No I haven't. I've heard AC Propulsion's numbers. The one that interests me is the 30 to 60 in a second and a half. The car has a top end of 90 and that's limited by the red line on the motor, it was a design choice they made not to put in a multi-speed transmission, which I think was a good one, to save weight. And then they picked a final drive ratio that gave them you know this bone-wrenching acceleration off the bottom and set the top end at ninety. And I think that was a good [setup].

EVW: You know people are gonna read this and want to buy one.

KA: Actually what I'd like to do is buy one of the RAV4's when they're available for sale. I think Toyota just announced they would be in February, 2002, ....take it down to AC Propulsion, rip the drive train out and put AC propulsion's motor in.

EVW: It's an idea... I'm surprised that they're combining the excellent acceleration with the good range. I guess it's the low weight of the vehicle helps that. But they have really good range for a car that can drag race with the Diablo. We're talking what, 90 miles or... I think you said?

KA: Yeah 95. Not when it's driven, drag racing with the Diablo. When it's driven efficiently.

EVW: The car that you carried out those tests with ... I assume had a pretty good battery pack in it, not the worn-out one you're talking about?

KA: No it's the worn-out one.

EVW: It's the one that you have?

KA: Yeah with the worn-out pack.

EVW: So the car with the worn-out pack still beat the Diablo?

KA: Yeah.

EVW: Yikes.

KA: Now there were a couple of things to note. The pack was fully charged when we started the day. And anytime we took a break we put it back on as fast a charger as we could. So we did our best to keep the pack fully charged. And we also kept it warm. We thought we had turned the battery heaters on the night before but there was a little user error and they weren't on. So the first thing we did in the morning is we went out and heated them up by alternately flooring it, letting the car accelerate, taking your foot off the pedal, letting it regenerate.

We repeated this process until the batteries were heated up to around 40 degrees C, because you get so much more power out of them when they're hot. Of course, the Diablo was also allowed to warm up.

EVW: Well you know, again, I think people are gonna read this and want to pick one up. I just hope that he is able to put things together so that either he can deliver cars at a price or realize his dreams of providing the drive trains for people who might want to put them in other cars.

KA: You know I think this would certainly be nice if they could deliver them for, I think they said something about $85,000 was their estimate as a sports car. I think there is a market for the car at $200,000.

EVW: A car for what?

KA: I think there's a market for tzero, twenty or thirty a year, at $200,000.

EVW: Umm, ... yeah if they can smoke a Diablo.

KA: Yeah if you look at what Diablo and Ferrari 355's are costing and recognize that this is a car that's playing in that arena, then it should clearly support a price of $200,000.

EVW: If he's gonna sell or consider selling the drive train I know some guy who has a VW bug who would be interested in talking to him.

KA: Actually they've done that conversion of one of the new VW Beetles.

EVW: AC Propulsion has?

KA: Yeah. It has the same drive train as the tzero in it.

EVW: That... that's definitely a good Q-car I think. :-)

KA: Yeah, they did under contract to VW. VW owns the car. Actually there's a little footnote here when I say the same drive train. The software that controls the magnetic field for the motor, they tuned for each application. For the one in that car it's tuned differently. They normally say this drive train is good for 150 kilowatts of power.

However in the tzero they've up-rated it to 165. The reason is that it's such a light car it can't do 165 for very long because you're in a blink doing 90 miles an hour and then there's not place for the power to go. So they're able to put more power into this motor than it was otherwise designed for, which was the 150.

EVW: Yeah sounds almost like you would be unsafe.

KA: Well no it's because the heat buildup isn't there. You can't do it for long hours simply because you can only have 165 kilowatts from 0-90 and that only takes so many seconds. Then it has time to cool because you're not gonna be able to put 165 kilowatts in it anymore. So it's 150 instead of 165 in the VW.

EVW: Slightly less horsepower.

KA: Nevertheless I think if you compare. Both EV1's I think have about 100 or a 90-kilowatt motor? I think the RAV4 is closer to 70 or 80. I forget the numbers on that.

Coming Next Week.... Adelman talks about his other EVs and how they perform.

Times Article Viewed: 13953
Published: 19-Jan-2002


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