GRA wrote:The question is, how much do those battery packs weigh, i.e. what's the payload, and is this the 300 or 500 mile pack in the tractor?
That's a good question, but even fully unloaded, this trip likely required the consumption of at least 300 kWh and traveled over 250 miles. As such, this is an important demonstration of the truck's capabilities. This route also demonstrates operation capabilities such as the operation of Megachargers at both ends of a route.
I didn't see any mention of Megachargers in the article, but I just skimmed it. Was that mentioned?
GRA wrote:Coming downhill from the Gigafactory the range was not going to be the problem, except possibly for the 300 mile tractor in snow with delays;...
"Coming downhill" makes it sound like these trucks just coasted 258 miles from the Gigafactory down to the main factory. In fact, while there was a NET elevation change of about -4500 feet from about 4500 feet down to about 50 feet, the trucks have to CLIMB about 2700 feet as they leave the Gigafactory to about 7200 feet in order to cross the Rocky Mountains at Donner Pass.
Reg, like most northern CA skiers I've made the drive (both ways) many times, so I'm well aware of the elevation changes. Coming from the Gigafactory through Reno, and then winding through Truckee Canyon and often all the way up to Donner, the speeds are often restricted. More importantly, if a 300 mile tractor leaves the GF fully charged, the 60 miles/+2,800 ft. to Donner Summit opens up room for regen, which will be gained at a very high rate (this stretch westbound is where the truck runaway ramps are located) until you get down to just past Penryn:
Plug this into a gpsvisualizer profile: https://goo.gl/maps/AYFaLVqU5az
Once in the Sacramento metro area the freeways back up unless it's well outside of commute hours, and along I-80 the Sac. Metro area merges directly into the Bay Area where you turn south along I-880, where the same applies. The option is to go south on I-5 and then west on I-205/580/680 to Fremont, but that way you have to go through the built-up area around Stockton and then hit traffic from the east side of Altamont Pass westwards (again barring night/early morning trips). They'll need to make numerous runs at a variety of times on both routes for test purposes.
GRA wrote:...it's the loaded uphill run (I'm assuming they won't deadhead uphill, as that would be idiotic when the Gigafactory will need supplies from the Bay Area).
That's true only as long as the trailers used for the batteries are compatible with the other loads. It is my understanding that many of the raw materials headed for the Gigafactory are containerized when they arrive in the Port of Oakland. Tesla may find that they need to load their batteries into containers in order to keep all of those containers from stacking up in Nevada. Since a fully-loaded Tesla Semi is simulated to consume about 630 kWh when traveling from the main factory up to the Gigafactory
, the aero impact of a container trailer should not greatly impact the ability to accomplish this mission.
Fortunately the Tesla Semis will be soaking in a warmer climate prior to the more difficult climb.
The packs should fit in a container no problem (internal width about 7'8" IIRR, although whether or not the packs can be loaded lengthwise side-by-side may be a problem), the issue will be do they have to transport special racks up the hill to stack them, if so do they fold, and what do the racks weigh? I've used (non-folding) racks similar to the one on the right end of the upper gallery row here: https://tier-rack.com/application/shipping-racks.html
(the picture just left of that shows the same rack folded), but there's no way they could handle the weight of a battery pack, even if putting that much weight that high up were acceptable. A battery pack could use a much lower, stronger rack. As battery packs are dense commodities maybe stacking won't be required, and using regular dunnage (plywood, foam, pallets, inflatable bags) and shipping them in a single layer will be okay.
The other option, and one that may make sense is to haul the containers to the Livermore warehouse or else a trans-shipment warehouse at the Port (in my Teamster casual days I sometimes worked at one), and consolidate 40' container loads into 48' or 53' trailers before hauling them up the hill. It will probably depend on whether or not trailers fully loaded with packs are weight critical and can't be fully loaded in any case.
GRA wrote:So, a useful start and will allow them to gather some performance data that can be fed back into the design, but unless they start doing this routinely, it's merely a test.
In typical GRA fashion, you try to minimize accomplishments achieved by BEVs. In this case, you are doing it by completely ignoring the stated goal of Tesla to transport their batteries from the Gigafactory to Fremont using the Tesla Semis
Jerome Guillen, VP of Trucks, Tesla wrote:We will use our own truck to carry cargo in the US between our different facilities. We have an assembly facility in California, the Gigafactory in Nevada, so we will use our trucks to carry things in-between.
I have long been a big proponent of companies consuming their own products when possible. There are many benefits which result from companies doing this. In the case of Tesla using the Semis to support their manufacturing efforts, this is an excellent way for them to live in their customers' shoes and share their experiences with the product. This approach ensures that the proper focus stays on the issues which exist in the Tesla Semi and encourages constant product improvement. They should also save money by doing this, assuming rail transport is not cheaper.
Self-consumption of products also allows a company to provide experiential data to their customers in order for them to better evaluate how the product might meet their needs.
The reality we are seeing with this demonstration is that battery-electric trucks can and will start carrying a significant amount of freight all around the world in the near future. Everything is now in place for this market to start to take off. There are significant applications for the two versions of the truck which are proposed. As time goes on, the capabilities of these trucks will grow into further applications.
Reg, I'm not ignoring that they plan to do this, I've said upthread several times that this is an excellent use for these tractors, and a good way to demonstrate the product. But a single run in good conditions is a long way from a fully operational vehicle. If they'd made the run last week, when it was snowing heavily and blowing hard along I-80 in the Sierra they would have gotten some data in worst case cold conditions, but given how new the tractors are and the inevitable problems that will arise even in good conditions, that wouldn't have been wise for a first run.
It's a pity they weren't able to do this kind of baseline run earlier so that they could get a bad winter weather test in, because there's a good chance that they'll now have to wait until next winter for similar conditions. This year is already looking like we're heading into another drought:
https://www.sfgate.com/news/article/Eve ... 729418.php
Even after storm, California’s Sierra snowpack at 37 percent of average
The likelihood of major winter storms (which have been notably absent this year) this late in the season is increasingly unlikely.
At least they will have plentiful opportunities to test the tractor in hot conditions this summer, so that can give them lots of info on heating of components on the climb(and regen heating onthe descent) and show where improvements are needed. BTW, the photos here show two different roof airdams, which appear to be used on regular and high-cube trailers: https://insideevs.com/new-tesla-semi-im ... r-surface/
Notice the Hyundai logo on one of them.