Funny, I was thinking the same thing while I was watching the pikes peak video and the driver was talking about how quiet the car is.
It might open up some new riding areas tho. Just be careful not to run over a x-country skier. Lol
How long before we have an electric Rocky Mountain King?
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Funny, I was thinking the same thing while I was watching the pikes peak video and the driver was talking about how quiet the car is.
It might open up some new riding areas tho. Just be careful not to run over a x-country skier. Lol
I'll still say it, but the fun part is that my riding buddies will be able to hear me. Haha
I'm sure electric sleds are coming from one or more major manufacturers eventually, but current battery technology would severely limit mountain and back-country riding. Steep and deep riding takes a ton of power, obviously, and regenerative charging would only get a little of that back – think about how quickly you coast to a stop on the level in deep snow. To have good range would mean a ton (perhaps literally) of batteries, which quickly becomes self-defeating.
Where electric sleds could shine would be in something like a resort setup: you could have warming/charging huts scattered around the trails and play areas. And unlike a road trip, it's not much of an imposition to stop regularly for a half hour or so. The only workable concept I see for mountain riding would be to have a mule sled or two with a generator that could get close to the action. You'd still be range-limited, but you could go play for an hour or so, then bring it back to charge (could be nearly seamless if the batteries were easily swappable). Not sure about Yellowstone: at the moment I don't think the EPA is super worried about it, but obviously that could change. And someone will always find a reason to complain...
Where electric sleds could shine would be in something like a resort setup: you could have warming/charging huts scattered around the trails and play areas. And unlike a road trip, it's not much of an imposition to stop regularly for a half hour or so. The only workable concept I see for mountain riding would be to have a mule sled or two with a generator that could get close to the action. You'd still be range-limited, but you could go play for an hour or so, then bring it back to charge (could be nearly seamless if the batteries were easily swappable). Not sure about Yellowstone: at the moment I don't think the EPA is super worried about it, but obviously that could change. And someone will always find a reason to complain...
buttttt.....if we have electric sleds, what would the environmentalists complain about?
Battery performance suffers in cold temperatures...and they are very heavy. It would be interesting to see what the final weight of the sled would be and if it could keep a full charge all day.
I don't like electric cars. I like my sports cars naturally aspirated, light, loud and with a manual transmission. Makes for a great experience.
And I don't think I want my sled electric. Not yet, anyway.
I don't like electric cars. I like my sports cars naturally aspirated, light, loud and with a manual transmission. Makes for a great experience.
And I don't think I want my sled electric. Not yet, anyway.
What is your experience with regenerative technology?
What an I missing?
Why can't a driveshaft that's spinning all day generate charge to the batteries? Remember the generators we used to our on our bikes in the 80s that would run a headlight and taillight as long as the tires were turning?
https://www.walmart.com/ip/DZT1968-...7760&wl11=online&wl12=782115819&wl13=&veh=sem
What an I missing?
Why can't a driveshaft that's spinning all day generate charge to the batteries? Remember the generators we used to our on our bikes in the 80s that would run a headlight and taillight as long as the tires were turning?
https://www.walmart.com/ip/DZT1968-...7760&wl11=online&wl12=782115819&wl13=&veh=sem
Here ya go, Scott. And anyone else who is curious.....
In a battery-powered electric vehicle, regeneration happens during braking, it is the conversion of the vehicle’s kinetic energy into chemical energy stored in the battery, where it can be used later to drive the vehicle. It is called “braking” because it also serves to slow the vehicle; and referred to as “regenerative” because the energy is recaptured in the battery where it can be used again. And totally different than the light on a bicycle many years ago. Unless you want to pedal your sled, in that case human energy could contribute to recharging.
The kinetic energy stored in a moving vehicle is related to the mass and speed of the vehicle... All else being equal, if your car (or sled in this case....) is twice as heavy it has twice the kinetic energy and if it is moving twice as fast it has four times the kinetic energy. Any time your car slows down the kinetic energy stored in the vehicle has to go somewhere. Let’s take a look at where this energy goes. There is always some kinetic energy consumed by the rolling resistance, mechanical friction, (lots of this in the sled drivetrain as we know it) wind resistance and the biggest one (IMO) would be drag from the deep snow we love so much..!!!! These bits (or large gobs) of energy go into heating the surrounding air, and various spinning parts in your machine. But the vast majority of the kinetic energy is converted into heat by your brake pads (in a car anyways) when you stomp on the brakes; this would be when regenerative braking recovers some energy that would otherwise have been wasted in the brakes.
How much energy does it recover?
Even in electric cars, the adage “your mileage may vary” applies to regen as well. The amount of energy you can recover depends on how and where you drive. From the powertrain point of view it looks pretty good. The energy conversion efficiencies from chemical to electrical (battery), DC current to AC current (inverter), electrical to mechanical (motor), and torque to force (transmission and wheels) are all quite high and work just as efficiently returning energy into the battery. The bigger problem is aerodynamic losses and higher speeds and rolling friction of the tires. These both act to slow the car, but the energy dissipated cannot be recovered. We must also remember that, even though the battery-to-wheel conversion efficiency is pretty good (up to 80% or so), the energy makes a full circle back into the battery and it gets converted twice for a net efficiency of at most 80% * 80% = 64%. Now pause for a moment and compare this to a sled plowing through deep snow. And then add gravity. And then consider a couple other factors, such as how we ride (mostly laterally and diagonally, with the occasional decent requiring substantial braking (has anyone here ever replaced brake pads on a mountain sled?? I haven’t,...)
And also consider how easy the track locks up during a descent; this should give a good idea as to how much energy could actually be recovered.
Any other thoughts on this? Or am I just confused?
^^ Thats a good summation.
I'm into Formula 1 racing and they use the KERS (Kenetic Energy Recovery Systems) system along with a turbo engine. This extra electric power can be depleted very quickly and then they have to go a lap or 2 before they have enough energy stored again for use.
But as you mention at the end. You need friction and braking to recover that energy, which I'm not sure is possible on a mountain sled.
I'm into Formula 1 racing and they use the KERS (Kenetic Energy Recovery Systems) system along with a turbo engine. This extra electric power can be depleted very quickly and then they have to go a lap or 2 before they have enough energy stored again for use.
But as you mention at the end. You need friction and braking to recover that energy, which I'm not sure is possible on a mountain sled.
That's a pretty good and thorough explanation, 'Cat.
The way I think of it is this: Start with a theoretical closed system – with no aerodynamic resistance, no rolling resistance, frictionless bearings, and a perfectly efficient motor/generator – in that scenario, a vehicle could start and stop indefinitely using regenerative braking, as well as going up and down hills. Now you add all those things back in, and you've got constant energy loss as long as a vehicle is moving, but not a massive amount relative to the size of the vehicle. The big advantage of regenerative braking is in frequent stop and go operation, because instead of a constant cycle of burning gas to accelerate and then converting that kinetic energy to wasted heat via the brakes, you can recover much of it by turning a generator. That also translates to going up and down hills, but in either case the frictional losses are constant. Fortunately, for a aerodynamic vehicle with high-efficiency this and low rolling resistance that, it really doesn't take a lot of power just to cruise down the road, and the demands of acceleration are brief and easily handled.
Now consider a snowmobile. They're not as efficient as a wheeled vehicle even under the best of circumstances because the track introduces so much friction in and of itself. The longer the track and the bigger the paddle, the greater the loss – I think I read somewhere that at speed a free-spinning mountain track takes up 40-50 HP on its own. So you've got significant losses before you add in the snow. With snow, especially deep snow, you lose a lot of energy just to plowing through it – it's like a constant braking force. Then it gets worse, because to drive you forward, you have to displace a lot of snow with the track, and a significant amount of that snow doesn't contribute to pushing you forward. A snowmobile, especially a mountain sled in deep snow, is a very power-hungry machine from a friction standpoint.
That's where electric power is at such a disadvantage. The drive system itself has great power-to-weight, but the storage (batteries versus gasoline) is terribly lop-sided. Gas has around 47 mega-joules per KG, a li-ion battery has 0.3. Gas has 150 times the energy per weight. It does get better when you factor in the efficiency of an electric motor compared with an internal-combustion engine, but gas still has roughly 50 times the energy per weight when corrected for that. So, to have any range at all, you have to weigh things down with a ton of batteries. It's not as big a deal with a car because there's so much less friction. On a sled though, you have such a huge amount of power being taken by frictional losses – losses that get worse the more weight you add – that the current battery technology seems to be a non-starter for many applications. The gains from regenerative braking are largely swamped by the frictional losses; wild guess, but just going straight up a slope and back down, you'd probably get back 30% of what you just burned, and that's the best-case riding scenario. As with electric cars, more so really, you keep coming back to the problem of the battery. And that's before you consider the already-strained natural resources required to make a li-ion battery. So, an electric sled might make sense here and there, but don't get too excited unless you see some significant battery breakthroughs.
The way I think of it is this: Start with a theoretical closed system – with no aerodynamic resistance, no rolling resistance, frictionless bearings, and a perfectly efficient motor/generator – in that scenario, a vehicle could start and stop indefinitely using regenerative braking, as well as going up and down hills. Now you add all those things back in, and you've got constant energy loss as long as a vehicle is moving, but not a massive amount relative to the size of the vehicle. The big advantage of regenerative braking is in frequent stop and go operation, because instead of a constant cycle of burning gas to accelerate and then converting that kinetic energy to wasted heat via the brakes, you can recover much of it by turning a generator. That also translates to going up and down hills, but in either case the frictional losses are constant. Fortunately, for a aerodynamic vehicle with high-efficiency this and low rolling resistance that, it really doesn't take a lot of power just to cruise down the road, and the demands of acceleration are brief and easily handled.
Now consider a snowmobile. They're not as efficient as a wheeled vehicle even under the best of circumstances because the track introduces so much friction in and of itself. The longer the track and the bigger the paddle, the greater the loss – I think I read somewhere that at speed a free-spinning mountain track takes up 40-50 HP on its own. So you've got significant losses before you add in the snow. With snow, especially deep snow, you lose a lot of energy just to plowing through it – it's like a constant braking force. Then it gets worse, because to drive you forward, you have to displace a lot of snow with the track, and a significant amount of that snow doesn't contribute to pushing you forward. A snowmobile, especially a mountain sled in deep snow, is a very power-hungry machine from a friction standpoint.
That's where electric power is at such a disadvantage. The drive system itself has great power-to-weight, but the storage (batteries versus gasoline) is terribly lop-sided. Gas has around 47 mega-joules per KG, a li-ion battery has 0.3. Gas has 150 times the energy per weight. It does get better when you factor in the efficiency of an electric motor compared with an internal-combustion engine, but gas still has roughly 50 times the energy per weight when corrected for that. So, to have any range at all, you have to weigh things down with a ton of batteries. It's not as big a deal with a car because there's so much less friction. On a sled though, you have such a huge amount of power being taken by frictional losses – losses that get worse the more weight you add – that the current battery technology seems to be a non-starter for many applications. The gains from regenerative braking are largely swamped by the frictional losses; wild guess, but just going straight up a slope and back down, you'd probably get back 30% of what you just burned, and that's the best-case riding scenario. As with electric cars, more so really, you keep coming back to the problem of the battery. And that's before you consider the already-strained natural resources required to make a li-ion battery. So, an electric sled might make sense here and there, but don't get too excited unless you see some significant battery breakthroughs.
I totally agree.
But I will also admit that as recently as ten years ago I would have bet on it that the technology wouldn’t be anywhere near where it is today. So who knows what may be possible in another 5 or 10. But I won’t be investing any money into Taiga anytime soon.
But I will also admit that as recently as ten years ago I would have bet on it that the technology wouldn’t be anywhere near where it is today. So who knows what may be possible in another 5 or 10. But I won’t be investing any money into Taiga anytime soon.
I believe the issue is using the power from the battery and sending power back to the battery at the same time.
Now, if u have two separate batteries, u can run the motor with one battery while charging the other and switch back and forth between the two.
Problem with that is now u have twice the weight in batteries.....
My concern with a mountain sled and lithium batteries, the amount of impacts with unmovable objects involved with mountain riding....
There are special procedures for the Fire department with handling electric cars, specifically the lithium ion batteries. Unlike gasoline, the batteries are their own ignition source!
Could be minutes after impact or even days later..........
[emoji507][emoji192]
it's the Law of Conservation of Energy. From WikiPedia (https://en.wikipedia.org/wiki/Conservation_of_energy - Which I think has it correct if I remember my high school physics correctly) -
"In physics, the law of conservation of energy states that the total energy of an isolated system remains constant, it is said to be conserved over time. This law means that energy can neither be created nor destroyed; rather, it can only be transformed from one form to another.....A consequence of the law of conservation of energy is that a perpetual motion machine of the first kind cannot exist, that is to say, no system without an external energy supply can deliver an unlimited amount of energy to its surroundings."
Even if you had switching batteries you would still pull some energy for the recharge and thus not achieve full potential and eventually drain the batteries. Any electricity you generate would be offset by the torque required to keep the shaft spinning.
That said, even on a finite charge, say 6-8 hours you can get some pretty good riding in.
"In physics, the law of conservation of energy states that the total energy of an isolated system remains constant, it is said to be conserved over time. This law means that energy can neither be created nor destroyed; rather, it can only be transformed from one form to another.....A consequence of the law of conservation of energy is that a perpetual motion machine of the first kind cannot exist, that is to say, no system without an external energy supply can deliver an unlimited amount of energy to its surroundings."
Even if you had switching batteries you would still pull some energy for the recharge and thus not achieve full potential and eventually drain the batteries. Any electricity you generate would be offset by the torque required to keep the shaft spinning.
That said, even on a finite charge, say 6-8 hours you can get some pretty good riding in.
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What's causing that shaft to spin in the first place?
You can regenerate from it only when you're not powering it to begin with. We're not coasting very often on sleds.
^ Exactly. You can't have a perpetual motion device in the real world.
My bet is 1-2 generations away from some form of electric sled coming from a major manufacturer, probably in the form of a trail sled, primarily for rental markets on groomers in Yellowstone or other refuge/park areas - at least that's where I see there being a decent market, assuming you could get 4+ hours of touring on a battery, with relatively quick charging (1-2 hrs). I also thought of a potential pitfall being that once one of these is in production, I don't know what would stop NPS from issuing a rule mandating that all sleds used in a NP must be electric. But that would be a ways off (hopefully).
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I question that battery technology is ready for recreational purposes. Maybe controlled environments like closed course racing, hillclimb events, etc.
The current electric motos run less than 2 hours with minimal wheel spin programmed into them. Sleds spin tracks like crazy in comparison. Real world recreational riding, and I wonder if you'd even get an hour on the trails, and 1/2 hour off trail. I see they're promising a lot more from the Taiga. I wonder if they control track spin in relation to forward momentum? That would work on the trails, but not off-trail.
I'm all for it once they're ready. But I also don't think the USFS will re-open any lands that are currently closed. Noise and pollution are just easy targets. The real reason for land closures is people who can't co-exist.
The current electric motos run less than 2 hours with minimal wheel spin programmed into them. Sleds spin tracks like crazy in comparison. Real world recreational riding, and I wonder if you'd even get an hour on the trails, and 1/2 hour off trail. I see they're promising a lot more from the Taiga. I wonder if they control track spin in relation to forward momentum? That would work on the trails, but not off-trail.
I'm all for it once they're ready. But I also don't think the USFS will re-open any lands that are currently closed. Noise and pollution are just easy targets. The real reason for land closures is people who can't co-exist.
DEAD CENTER BULLSEYE.
