AndyH said:
GRA said:
And a truck that has to meet a schedule and keep within his/her service hours isn't going to be able to adjust their speed to the extent you did.
I'm intrigued. How much did I adjust my speed, and how do you think your understanding of how I drive can be applied to the Tesla truck? :?
You have stated that you slowed down, well below speeds that line haul trucks typically travel at. Turn-around points are typically spaced so that a driver won't run out of hours while driving between them, with a cushion to allow for unusual conditions. Checking an old copy of the Teamsters' Western States Supplemental to the National Master Freight agreement, it specifies that turn-around points for single drivers can't be spaced more than 500 miles apart (note, these are layover points, where the driver then returns to the home terminal on his next trip). Of course, the Teamsters have far less of a presence in the trucking industry now than they used to and most trucking is now non-union, which requires drivers to drive even longer and faster if they can get away with it. If you routinely have to drive slower just to reach the destination even if conditions would otherwise allow it, you're going to have drivers running out of hours, and that's going to drive the TCO up as well as delay shipments, possibly imposing penalties. So you're going to have to move the turn-around points closer or provide two drivers, with one of them wasted for much of the time.
AndyH said:
GRA said:
AndyH said:
You might want to actually operate an EV for a year.
Operating one for a week gave me much of the info I needed, and selling battery-based off-grid systems gave me rather a lot of background about minimizing battery TCO over the long-term.
The only commonality between EVs and off grid systems with batteries is that they both have batteries. I used to build batteries and BMS for ebikes and motorcycles (and supplied prototype gear for a commercial motorcycle manufacturer with an initial near the end of the alphabet and a TTXGP race team). I've also built and instrumented off-grid LiFePO4 batteries for back-up power. Different battery types in different service does not provide much information that can cross between domains. A whole week? All righty then.
What would I have learned going beyond a week, that I couldn't have learned from reading here and elsewhere, as well as my own experience? I know the factors that affect all batteries, how to maximize range etc., the specific usage usage depends on the chemistry. How does living with a single car for a year give me anything other than anecdotal info for my specific circumstances and that one battery pack?
AndyH said:
How will charging to "100%" affect the TCO? It depends on the battery type, the thermal management system, the ambient climate, the load, the driving style, etc.
Quite so, and until the companies have the data to determine that, any claim by Tesla re TCO is unverified. The same goes for DoD. Now Jeff Dahn, who consults for Tesla and is largely responsible for the NMC chemistry they use in their power packs, has recommended that for best longevity the car packs should be charged to no more than 70% and not discharged below 30%. Obviously, you can go above and below those numbers with some greater degree of degradation, but for minimum TCO no one is going to use 100% DoD regardless of the chemistry. So, any claim of 500 miles of range based on 2kWh/mile and 1MWh
total pack, which are Tesla's
announced values, are maximums that will never be used in service, just as the announced max. ranges of their cars are unlikely to be except in emergencies, unless the owner simply doesn't care about longevity or TCO. Such behavior doesn't describe any trucking company I know of.
AndyH said:
GRA said:
Considering that even if a full charge with a hypercharger takes 2x 30 minutes to complete, the second period from 80-100% results in about 2 1/2 hours of drive time. Since trucks aren't making money unless the wheels are spinning, that's likely to be a worthwhile use of time - especially if it's needed to get to the next stop. If the driver ends up stuck on a closed road in a blizzard and has to use battery to stay warm and alive, I'm thinking that extra charge will be appreciated in that mode as well.
Okay, now if the driver is paid for the time they spend stopped, or if they're paid by the load, sitting twiddling their thumbs needs to be less expensive than being out on the road for 10 hours straight.
AndyH said:
GRA said:
Also, while obsessing over the 'fast charging will kill my battery' even though it's been proven not to be the case, recall the costs to operate a class 8 tractor. No lube changes, orders of magnitude lower fuel costs, no overhauls, no broken axles, much less brake work... An EV tractor provides so much savings that concerns about charging to 100% is mouse nuts. (Please note that fuel is not included in the chart to follow.)
https://www.overdriveonline.com/whats-the-total-cost-of-ownership-of-a-class-8-truck-over-15-years/
And we've both included total costs of operation. What will matter is if the cost of fuel, maintenance etc. is reduced enough to compensate for the greater amount being paid to the driver and any delay in shipment, and until Tesla demonstrates that their trucks actually
are less maintenance intensive over the long haul (their cars certainly haven't been to date), any TCO numbers they provide are nothing more than guesstimates, which is why Ruan and I expect other companies will be running tests for quite some time. Will Tesla provide performance guarantees out of the gate, or else dry or wet leases where the manufacturer provides the trucks and handles all maintenance etc., at a specified cost/mile? Volvo's doing that with some of their BEV or PHEV buses and maybe trucks too, I forget, and while everyone's learning about the real capabilities of this new tech, I expect a lot more of that. OTOH, big companies like UPS can afford to experiment on a small scale, as they've been doing for more than a decade with BEVs, PHEVs, CNG, pneumatics and fuel cells.
[Edited to fix quotes]
