Long-time ABG friend and reader Jeff Turner wrote in to let us know about the latest adventure of the electric snowmobile built by his alma mater McGill University. Turner and his classmates first came to our attention with their success in the SAE Formula hybrid program. In addition to the warm weather hybrid drive race car, McGill has also been working on battery electric snowmobiles. Their first electric snow machine has done a fair bit of traveling over the last three years including spending two summers in Greenland.
The new edition of the snowmobile now has a 23 horsepower AC induction motor to go with its 3.2 kWh lithium ion battery pack. That pack will soon be replaced by a lower cost nickel-zinc unit. The typical snowmobile CVT has been discarded thanks to the new motor's 7,500 rpm maximum speed. The McGill machine now also has regenerative braking for the first time. The machine can now go 10 miles at speeds up to 35 mph.
For its latest outing, the snowmobile has been shipped to British Columbia, where recently it carried the Olympic Torch into the town of Whistler where most of the outdoor events, including downhill and cross country ski events, are taking place. Whistler-based Canadian Snowmobile Adventures has been one of the sponsors of the McGill program for several years in the hope that it will eventually yield a zero emissions snowmobile that it can use for its tours. Turner's description is pasted after the jump.
[Source: Jeff Turner, McGill Reporter | Image: Andy Dittrich]
A message from Jeff S. Turner
McGill Electric Snowmobile at Winter Olympics
Hey guys, you might remember having written a few pieces on the various EV projects at McGill... You've covered our ups and downs at the Formula Hybrid event since it started in 2007, and you also did a piece on our electric snowmobile.
Just after Sam covered us with this story:
the snowmobile traveled for a second time up to the NSF's research station on top of the Greenland plateau, where it helped researchers collect snow samples in the "no-emissions zone" 5 miles out from the base's generators on a daily basis throughout the summer.
Last year, the snowmobile traveled to Val d'Isere up in the French Alps to serve as a workhorse during the FSI World Alpine Ski Championship, mainly lugging a trailer to collect recyclables, but also carrying some of the winning athletes to the podium.
But this month is probably the snowmobile's highest profile gig yet, starting off by carrying the Olympic torch into Whistler, the town about two hours from Vancouver that will be hosting most of the outdoor events. Anyway, more info about that event can be found at the "related URL", an article from the McGill Reporter. Canadian Snowmobile Adventures is a snowmobile tour operator in Whistler, and they've supported us for the past few years in hopes of developing an electric snowmobile that would be perfect for some of their beginner snowmobile tours, so they're the ones responsible for putting the snowmobile into this international spotlight. I was hoping you guys might be able to help us spread the word!
On the more technical side (since most people on Autoblog like me are interested in the details!), this snowmobile is a pretty serious upgrade over the last one reported on ABG. The battery pack is still the same 72V, 3.2kWh li-ion pack, for now anyways, more on that in a bit. But the drive system is all new. We've switched to a 3-phase AC induction motor, with 23hp peak, and 30lbs-ft from 0rpm. This motor can spin up to 7500rpm, so we were able to ditch the more or less stock snowmobile CVT for a direct drive system. Now this snowmobile won't satisfy those looking to blast across frozen lakes at 120mph and go on 150 mile weekend trips. This machine is really meant for a utility role, but never the less, it's quite a lot of fun to drive, and in my opinion, is a much more pleasant way to actually enjoy being in the woods and should give you a much better chance to see some wild life. All told, this should be perfect fit for beginner snowmobilers who come to CSA in Whist
ler looking for a day of fun in the woods. Top speed is about 35mph, and those 3.2kWh should get you about 10 miles of riding, though the battery is happy to be partially recharged at any of the stops along the way.
One of my favourite features, thanks to the new AC motor controller, is actually the regenerative braking. Now McGill has historically shunned regen brakes in snowmobiles, as we never thought there was much to get out of it, snowmobiles don't exactly coast very much! But our eyes were opened while doing some testing with CSA in 2008 in Whistler. After climbing to the top of Whistler, we let the snowmobile recharge for a few hours while doing a spot with the local news before heading back down. Of course we realized how cool it would be if we didn't need to plug it in to recharge at the top, and instead just regened all the way back down. It hit us that yes, in a role where an electric snowmobile actually deals with drastic altitude changes (any ski hill workhorse), there is a lot to be gained from regeneration.
But that's not all! Regen can actually help a lot in maintaining control while descending the ski hill. Experienced riders of gas-powered snowmobiles will often feather the throttle while going downhill, in order to engage the centrifugal clutch and allow for engine braking. That's because using the regular disc brake runs the risk of locking up the track, and causing the snowmobile to skid and possibly slide sideways which could lead to a nasty rollover. The electric snowmobile in 2008 though did not have regen braking, and therefore we were forced to use the regular brake to control our decent, and it was a scary ride with lots of sideways motion!
This year though, we have a much more mountain-friendly electric snowmobile. The motor controller is programmed to automatically apply slight regen braking whenever the throttle is let go (the kind of thing that drives Mini EV drivers nuts!) We can easily play with this setting to control how strong it is, but it's always just a fixed amount of regen. What we can do though, is flick a switch and put the motor controller into reverse. With this controller, you can actually switch from forward to reverse with the throttle pinned, and it'll smoothly bring you to a stop before accelerating backwards. So going downhill, you can pop into reverse gear, and your throttle suddenly becomes a perfectly progressive regen brake pedal. There's no messy blending of regen and regular hydraulic brakes to speak of. And it even mimics the throttle feathering trick used in gas power snowmobiles to engage the clutch, so it shouldn't be too hard to adapt for experienced riders.
On the battery front, we are indeed still running the same old li-ion pack, but we have brand new batteries of a brand new chemistry that just didn't come in on time to be integrated into the snowmobile for the Olympics. These are Nickel-Zinc batteries that should drastically reduce the overall cost of the electric snowmobile and turn it into something with some real market potential. While we haven't had much time to test these batteries for ourselves, the specs suggest we should be able to get a similar energy capacity of 3.1kWh with a 56kg Nickel-Zinc battery pack, with a total price tag of $1200 US. Meanwhile our li-ion pack weighs about 40kg and it's market price hovers around the $5000 mark.
Once the snowmobile returns from the Olympics, the McGill Electric Snowmobile Team will once again head to the SAE Clean Snowmobile Challenge in Houghton Michigan, with the hopes that these batteries will help make the McGill snowmobile the most affordable EV at the competition.
In the mean time, keep your eyes and ears peeled for an eerily silent snowmobile on any coverage of the Winter Olympics.
Here's a youtube clip of the snowmobile with the Olympic torch in Whistler, skip to about 5 minutes in to see injured Whistler Olympian Julia Murray carry the torch up to Steve Podborski (former Canadian Olympian and one of the famous Crazy Canucks) who then skis the torch back down the slope to light up the cauldron.
If you can reply to me by email, I can send you a few high res photos of the torch being lit on the snowmobile.