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As someone who owns a long range EV I don't see trucking/towing going away soonish. Even towing marginal 6-8k loads we see ~11mpg in our efficient truck(v6 turb
by vvanders 8y ago
As someone who owns a long range EV I don't see trucking/towing going away soonish. Even towing marginal 6-8k loads we see ~11mpg in our efficient truck(v6 turbodiesel). The energy density just isn't there for 100mi+ trips.
That said I'd kill for a diesel electric truck, love the torque and smoothness of our EV.
- toomuchtodo 8y agoTesla’s new Raven motors and a more energy dense pack based off the 2170 cells in the Model 3 make this use case within reach. Their Semi is dragging a 80k tractor trailer load (concrete blocks) around to demonstrate the high end working. Disclaimer: I occasionally tow ~2500lbs with my Model S. Works very well, no Auotpilot though while towing.
- erk__ 8y agoHow much does the range degrade when towing?
- toomuchtodo 8y agoI lose 40-50% of range, depending on the weight and aerodynamic profile of the load; went with a 100D to mitigate the reduced towing range.
- salty_biscuits 8y agoI wonder how much range you could get back with a trailer equipped with regenerative breaking? Or if it would be too much for the battery to cope with?
- toomuchtodo 8y agoThe vehicle recovers the collective momentum of both it and the trailer when braking.
- salty_biscuits 8y agoThe trailer is unbreaked? That seems rather dangerous!
- deleted 8y ago[deleted]
- toomuchtodo 8y agoOnly need trailer brakes if the gross weight is above 3000lbs in my jurisdiction. I also keep the speed reasonable when towing to prevent jackknifing or oscillation.
- salty_biscuits 8y agoI think I implicitly assumed that the 40% reduction in range you mentioned was due to a larger load than it sounds like you are carrying. It would be interesting to see if the car was using regenerative braking less with the increased load. Also the break down of where the extra energy is going (i.e. aero, rolling resistance, hills and acceleration etc). Would depend a lot on the type of driving you are doing, but I would have imagined that extra mass is less of a problem for electric vehicles since there is the opportunity to recover potential energy.
- toomuchtodo 8y agoIts the aerodynamics for sure that kill my range and double my per mile energy usage. Petrol tow vehicles have so much more energy density available to them, their aerodynamics are less of an issue. Still, no problems towing a Waverunner to the beach or an antique sewing machine to a friend’s house from a craigslist find.
- salty_biscuits 8y agoSounds like an opportunity for trailer manufacturers to make aero trailers for electric vehicles...
- jseutter 8y agoWhile I think you're right, I do want to correct you on something. Class 8 trucks like the Tesla semi have an 80,000 pound total weight, hence the name 'Class 8'. Typically the truck and trailer weighs 32,000 pounds leaving 48,000 pounds for cargo. Average cargo weights are in the 35,000 pound to 45,000 pound range. If the Tesla semi significantly raises the empty weight of the truck it will limit the amount of cargo that can be carried. A load of toys will be nowhere near the weight limit but a load of milk products will easily exceed it. Some states allow increased Class 8 loads as high as 115,000 pounds, mitigating the weight issue. My guess is that Tesla will try as hard as possible to match the weight of existing trucks. It is interesting that they haven't released weights, perhaps because they don't yet know or because it is bad news. If it was lighter I imagine Elon would have mentioned it multiple times in tweets. https://www.teslarati.com/how-much-tesla-semi-truck-battery-pack-weigh/ https://www.teslarati.com/how-much-tesla-semi-truck-battery-...
- deleted 8y ago[deleted]
- anticensor 8y agoFor metric people: Class N3 (35 tons), some states allow Class N4 (52 tons).
- EADGBE 8y ago> It is interesting that they haven't released weights, perhaps because they don't yet know or because it is bad news. I'm guessing the bad news part. My Half-Ton Silverado Crew Cab's (That's the 4-door smallest full-size pickup) curb weight is 4,942 lbs. The heaviest Tesla Model S' (biggest battery I assume) curb weight is 4,941 lbs. More weight spent on the cab and trailer is less weight spent on cargo, and money in the trucking industry is driven by how much you can carry (Speed is restricted, hours of driving are restricted, but amount cargo - other than weight - is not).
- rootusrootus 8y agoDefinitely makes more sense in the tractor-trailer market, where the additional battery cost will be easier to account for. Doubling the price of a pickup is probably a no-go, so a few more years at least before the pricing gets acceptable there.
- rootusrootus 8y agoMy napkin-math calculation suggests that to have an electric pickup capable of replacing our F150, I'd need a battery pack that would capable of pushing a Model S a thousand miles. Definitely within the realm of possibility, but introduces a non-trivial amount of extra cost at current battery pricing, and compounds the hassle of recharging. So I agree, we are quite a ways off yet from plausibly displacing ICE from pickups. At least in the full size pickups. Seems a bit more plausible in the Colorado/Ranger/Tacoma sized pickups that are less often used for towing.
- nanomonkey 8y agoI may be wrong, but you only need the extra battery capacity when towing. So it's possible that your trailer could be equipped with the extra batteries.
- vvanders 8y agoThat makes things worse, usually you want to less weight on the trailer. Right now I've got a 7.5k towing capacity, if a pack weighs 2-3k that cuts my towing capacity in half.
- dotancohen 8y agoDo you typically have things in the bed when towing? Just brainstorming, a removable battery pack that sits in the bed for when you're hauling would save weight when your not hauling. Is the towing capacity limited by the drivetrain or chassis? If it's drivetrain then I suppose that it does not help to move the batteries to the bed. But if you're chassis limited, then keeping those batteries off the towhook would help, no?
- rootusrootus 8y agoMost pickups reach payload capacity before the tow rating itself is reached. Payload includes everything -- driver, passengers, cargo, anywhere in the truck. To an extent, putting the batteries in the trailer does make a little more sense since it won't count 1 for 1 against payload (typically about 10-15% of the trailer weight will be on the tongue, for safety). For some reason I actually got downvoted for saying it in my original comment, but cost is a big consideration for now and why I think we're a ways off yet from full size EV pickups. Takes a big battery pack to tow an open parachute (what it feels like towing a high frontal area trailer ;-)) 300 miles a day. And then it has to be recharged, which can be a problem given that most people take RVs places that don't have great infrastructure.
- rfugger 8y agoLocomotives have been diesel-electric hybrids for decades, so it probably makes a lot of sense for trucking, I agree.
- vvanders 8y agoYeah, I've always been curious if running a diesel motor at optimum RPM offsets the conversions loss.
- Animats 8y agoLocomotives do that because they need to power many wheels, and because they need huge torque at zero speed to get started. Trying to do that with a very large clutch is painful. (There are locomotive-sized clutches for some smaller locomotives, and British Rail was once into that approach, but it's obsolete.) Modern locomotives run the motors as synchronous AC servomotors, locking all the wheels together in software. Freightliner has an electric semitruck.[1] So do MAN, Mercedes, Mitsubishi, etc. [1] https://www.youtube.com/watch?v=qwI4Wt5Av3k https://www.youtube.com/watch?v=qwI4Wt5Av3k
- lukasm 8y ago> diesel electric truck Ford my actually provide you with that. They showed a Ford Transit in Amsterdam last week. It has 75kW battery with 200km range, but you can order a diesel powered range extender for it. I think Tesla should partner up with a company that could add a range extender to the frunk.
- gridspy 8y agoThe entire design of Tesla's vehicles is based around no firewall, no exhaust system. They would have to put that all back in if they added an ICE.