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UK Students Build Electric Car With 248-Mile Range
da_how writes "A group of students and graduates at Imperial College London have built an electric car with a massive range — 248+ miles on a charge at 'reasonable' highway speeds (60 mph). They did this by filling the car to the absolute max with as many lithium iron phosphate batteries as possible — 56 kWh — and designing a very efficient direct drive powertrain, about 90% batteries-to-wheels at highway speeds. The choice of vehicle is an interesting one: it's a converted Radical SR8 — a track racing car with a speed record on the Nurburgring. Not an obvious contender for an endurance vehicle (no windscreen either!) — but then they claim it's lightweight to start with, being constructed of steel space frame and glass fiber. Also, Radical is based in the UK and provided some help and sponsorship. The students plan to drive their 'SRZero' 15,000 miles down the Pan American Highway, beginning July 8 in Prudhoe Bay, Alaska, and ending up in Tierra Del Fuego three month later. That's about 60 charges."
They made a monster battery to get a large mile range. That to me doesn't seem very functional since its still using the same tech, just a bigger fuel supply.
Attention... all grammer nazi"s! Is they're anything; wrong with: my post,
The Tesla Roadster has a 245 mile range. And basic stuff like bumpers.
The student car looks like it has about a 3 inch ground clearance. If that. That's not going to get very far on anything less than a perfect road. And they want to drive it down from Prudhoe Bay? Right.
The Dalton Highway, from Prudhoe Bay to Fairbanks, is unpaved. They might want a little more ground clearance than the car pictured in the article.
Seems like they wanted to take a summer trip and figured out a way to get someone else to pay for it. Not a bad deal.
And made the common mistake of ignoring the productivity of their work. Spending as much time in any other job would've paid the trip with less risk involved.
Yes, I know there are other benefits to their way. At the very least they can automatically beat any "I just came back from Chile" with their "I just came back from a trans-american road trip in an electric car I built with some other cool friends". We all know which one's gonna get the girl. In the pub next to the engineering faculty, of course.
One thing that stands out to me is that the rear spoiler and front splitter would make for a lot of aero drag, especially where the rest of the car is rather likely to be quite aerodynamically slippery looking at it's shape. They've also tackled rolling resistance and drive-train efficiency so any gains in aerodynamics would greatly extend range. At 60mph it's the greatest force acting on this car, and with their steps towards efficiency it is even greater. If they would just ditch the big spoiler and the front splitter, they'll watch their range shoot up. 0.50 to 0.30 cd might account for 40% improvement in a vehicle where rolling resistance has been already addresed.
Don't get me wrong what these guys are doing is great, but ~270 miles range is not terribly impressive considering that's what a stock Tesla has achieved.
Ditching the wing and splitter could have yielded them 20-40% improved range at open road speed, at the small expense of the race car look. It would take a few minutes with a spanner to remove, and to put back on for parking up for a photo shoot with the local press. I hope this is what they do. Some further work with some duct tape or some more ambitious aero mods with some coroplast http://ecomodder.com/forum/showthread.php/aerocivic-how-drop-your-cd-0-31-0-a-290.html ecomodder* style and they could have squeezed out more efficiency. The very best road vehicles approach 0.15 Cd, this would have given them a shot at 500 miles range. Lower the speed a little and they may have gone 600mi / 1000km.
I can't find Radcial SR8's aero stats anywhere but I know such track day specials have a fair bit of down force by design, so a drag coefficient above 0.50 is not uncommon. This is largely the result of the wings, air damn, and underbody design. High down force set up might be over 0.70 or more. To compare, a SUV is about 0.40, a good sedan 0.32, and a Toyota Prius 0.27, Aptera is about 0.17 these vehicles are not even designed not to generate lift let alone downforce.
* Yes I do lurk there.
After logging in slashdot still does not take you back to the page you were on. It's been that way for 20 years.
So?
The cars won't appear there overnight. They'll be bought gradually, and be mostly charged at night, when the grid has spare capacity. As the load grows, the places with least spare capacity left will be upgraded first. You don't have to do an "overhaul the entire US" project. And why would it need a stimulus? If people are spending more on electricity, that's where the funding for the infrastructure should come from.