Electric-Vehicle on The Infinite Unknown

Detroit Blows it Again

Jared Watkins — Mon, 11 Oct 2010 00:00:00 +0000

Wow… what were they thinking. In summary… it seems the claims that GM has been making for years about the design and performance of the Volt were just out and out lies. They claimed it was a serial hybrid.. meaning the gas engine was just acting as an electrical generator and that the electric motors drove the wheels. That’s a lie. They claimed it would get 230 mpg in city driving and have an initial electric range of 40 miles to cover the average commute. All lies. As people are finding out, this is nothing but an american built hybrid that’s not substantially different from what toyota has been building for over a decade. Actually that’s not totally right.. it is substantially different in one way and that’s the price.. it’s about 50% more expensive. <!-more–> Say what you will about the Chinese and their lack of respect for IP.. but when they want to copy something they just go out and do it. By comparison this ‘revolutionary’ car (that isn’t) has been in development for what.. 4.. 5 years at GM? Really guys… this is the best you can do… how pathetic. The only good thing that Might come out of this is using lithium based batteries rather than the nimh ones that the other companies are using. Of course.. since we don’t have confirmation on that yet either.. I’d hold off on buying more SQM. At this point I wouldn’t believe any claims they were making.

Now that I think of it.. remember that ad campaign that was around a few months ago where GM was bragging that they had paid back the bailout money? Yea.. that wasn’t true either and they finally copped to it last month. Moving money from one tax-payer pocket to another isn’t really the same as repaying the bailout.

So that’s two strikes against Government Motors now… two very public, very big, and very obvious lies. It’s nice to see the new management is demonstrating the same level of ethics, openness and competence as the rest of our federal government. Now I’m curious to see what will make it a trifecta. At this point it wouldn’t surprise me in the least if the new CEO Rick Wagoner held a press conference and announced that he was actually Xenu and had come to destroy the human race (and shareholder value) by selling us little econo-box deathtrap cars for over-inflated prices. That would at least make some little bit of sense for what’s been going on in that company lately.

40 Miles to the Charge

Jared Watkins — Fri, 30 Jul 2010 00:00:00 +0000

I’ve heard some… odd comments on the new Chevy Volt and just wanted to point something out. The above line ’40 miles to the charge’ is being said with a negative connotation… even suggesting that the battery should be the backup to the gas engine. The average commute is 20 miles.. and this was the target for the battery capacity… so lets do a little back of the envelope math.

Around here.. power costs about 9 cents per KWh and in round numbers this car will let you use about 9 KWH from the battery before it will fire up the gas engine to recharge internally. Assuming you can make a 40 mile commute and plugin when returning home.. drawing that power from the utility.. that would be a daily cost of about 82 cents. The average passenger car on the road today gets 23 mpg or about 1.7 gal of gas for that same commute which, at current prices (2.60/gal), would be about $4.52 per day. There are other factors of course.. both positive and negative.. like ‘spirited’ driving and regenerative braking but those numbers put a ballpark on the fuel costs. So over a month of commutes 5 days a week the costs are about $16.40 for the Volt vs. $90.40 for the non hybrid. Over a year that puts fuel costs at about $197 vs. $1085 just for that first 40 miles per day of travel.

That’s a pretty good savings.. even with gas prices being as low as they are currently. Now I’m not going to pretend you aren’t paying a premium for any hybrid.. but you would use a ton less petroleum and that’s a good thing.

Ebike: First 125 Miles

Jared Watkins — Wed, 29 Apr 2009 00:00:00 +0000

This is an update to my initial posting last July. It didn’t take long to figure out the lead batteries were not going to cut it for the sort of high performance bike I had in mind. So shortly after I moved I replaced them with a LiFePO4 pack from Yesa. I got this straight from the manufacturer in China at a considerable savings over other similar quality packs from retailers here. I can only speak for my experience.. but the guys at Yesa were top notch to deal with and after more than 6 months putting their batteries to work I’ve had no problems. The Li pack is lighter and I relocated it for better balance on the bike. With a fresh charge on level ground it can sustain 40… but 35 is a normal top speed once you get past the first few miles.If I had it to do over.. I might go with a 72v setup and a motor with more windings. That would allow for lower power draw but still ample speed when you need it. Continue Reading for more technical details..

It’s a 48v 20AH pack and with this motor (wound for speed) the power draw can range from 25-37 W/mi depending on what sort of riding you are doing. If there is traffic I try to keep up so that results in higher average speeds and quicker acceleration and higher power requirements. It’s not hard to achieve 25 W/mi, or better, by sticking to side streets with little traffic and keeping the speed under 20 or so. The long wheel base and low seating position makes it easy and comfortable to ride at speed and I’ve had no problems being seen by drivers.

By the numbers this pack has 960 Whr capacity so with a conservative (and kind) 80% depth of discharge that results in a range of between 20 and 30 miles depending on riding style. So far my trips have been between 4 and 6 miles round trip. That covers trips to the grocery store.. the bank.. the post office and some excursions uptown. At such a low depth of discharge that should make this pack last a good long while. At 48v you need the 20AH rating though because it’s very easy to draw the full 40A my speed controller is rated for. This again is where a 72v pack would a better fit electrically.. if not physically.. since that would reduce your current to a more managable 28A. With that level you could go with a 72v 15AH pack and still be within it’s 3C continous rating. Unfortunately Yesa does not have an off the shelf BMS or charger for 72v packs as yet.. and while you could rig something up with 2 36v packs.. there can be issues of uneven discharge putting them together in series since the separate battery management systems aren’t designed for that.

My first hybrid: an Electric Utility Bike

Jared Watkins — Mon, 07 Jul 2008 00:00:00 +0000

I’ve always been interested in alternative/distributed energy systems and that includes things related to transportation. So over the last few months I looked into the current state of things to find out if there is a viable electric vehicle that could be had today. While there are some very interesting things out there.. nothing is available in NC today or in the near future that is what I’d call reasonable. Some of the more interesting ones are the Vectrix and the Venture One. The Vectrix is a large electric scooter that has reasonable performance but what I’d call an unreasonable price of about 10k. The Venture One looks like a really fun tandem two seater that will be avliable in all electric or a nice hybrid drive system. No firm pricing or availiablity on that one yet though. Many of these new vehicles are being developed in CA and will only be for sale there for a while.. since no dealership or support system is yet in place for them.

So once I knew where I’d be moving I started work on another option, an electric bike. It’s now basically finished and I’ve started trying to get the hang of it. It’s based on an Electra Townie frame with the Xtracycle extension. The low seat and forward pedal position makes this comfortable to ride and even I can put my feet down without getting off the seat.. which should make it safer and easier to handle. The Xtracycle extension gives it a longer wheel base, cargo bags in the rear and a nice place to mount the batteries. To that I added a Crystalyte 5305 electric motor, Cycle Analyst computer, speed controller, and a 4 pack of 20AH BB batteries that are made for electric vehicle use. I seriously considered some of the new LiFePO4 (lithium iron phosphate) batteries but it seems there isn’t a good source for high quality, small quantity cells (that are the right size) or a proven battery management system for these yet. Hopefully by the time my pack is ready for replacement there will be.. I can then loose about 15lb and gain about twice the performance. Read more for a collection of Ebike and related links.

http://www.ebikes.ca

http://www.electricmotorsport.com/

http://www.valence.com/

http://www.thunder-sky.com/

http://www.exertrike.com/

http://www.electricrider.com/