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> A Diesel engine, transmission and fuel for 500 miles is about 5,000 lbs.

You often end up carrying more fuel than you need so you can buy it in cheaper places. And then there’s the whole art of timing your fuel stops around the weigh stations...

> still $100k cost just for the battery. The battery cost is as much as a new Semi's price.

That’s not that crazy if they can actually deliver on the operating cost savings they’re claiming. Big if though.

At 7 lbs a gallon for diesel most semis can carry 200 gallons so add an extra 1000lbs if you like, the Tesla still has to make up 5000 lbs while having 1/3rd the range.

Timing stops for megachargers will be a whole lot more difficult than truck stops until they are as ubiquitous. If you have to use a plain old supercharger your talking 8-10 hours for a charge, don't even bother with a normal plug of any kind.

Yeah no doubt, there are a ton of unanswered questions here. If they can't retrofit their existing chargers to "mega" status that would pretty severely limit the usefulness of this product.

It would be a slow rollout anyway. First customers would be people with ~200 mile routes, just charge at home base.

Then people with ~500 mile routes that can charge at both ends. grow from there.

It looks like the first big buyer is using them for those short-haul trips.

Does the Semi have a sleeper cab? If not, it won't be used on long-haul routes regardless of battery.

What's required for a sleeper cab? We got some shots of the interior and it looked easily big enough to add a bed or the like. With a battery that big heating overnight should be practically free.

Just the space to put a bed, storage, and possibly a small fridge and microwave.

Elon says that the truck will be charged by the end of the 30 minute DOT required break (14:06 into the livestream: https://livestream.tesla.com/).

Is that possible? Assuming 500 miles of range at 2kwh a mile is a 1000kwh battery, charged over 30 minutes, is 2 megawatts, if the voltage is the same as the supercharger (480V) requires 4000 amps...

Google says your average powerline carries 10k amps.. so it seems within reason, but it would require some power upgrades ;)

Power = amps × voltage . So no. They are 10kA × 3kV (well, depends on the line), so that gives us 30MW.

That's with a megacharger not a supercharger, there are no megachargers deployed anywhere yet. Megachargers are 1600 kilowatts vs 120 kilwoatts for a supercharger.

A charging station with 10 megachargers going at the same time will draw as much power as a small city of say 10,000 homes.

A municipality with only 10,000 homes isn't even approaching city status, more like a small town... but I get your point.

https://en.wikipedia.org/wiki/Settlement_hierarchy

At least the weight will be (measurably) consistent no matter how much charge is in the battery. That said, they still weigh more than diesel so I assume they'll pay more at the scales.

> they still weigh more than diesel so I assume they'll pay more at the scales

I'm not sure what you mean here. In the US, scales are used to ensure compliance with axle load limits, not to determine any costs.

In any case, since they don't need the weight of a diesel engine, transmission, fuel tanks, or emissions systems I'm not sure how the weight balance will work out.

If you take the Model S and scale it up then people have said the battery is half the cost of the car, and therefore the battery alone is roughly the cost of a normal car. I don't think it would be suprising if the same is true for the semi.

There's at least one rural delivery man who bought a Tesla Model S and paid for it by using the mileage payments he gets for his job. So as long as your route fits, the same kind of high up front cost being amortised over time applies. The more miles you drive the better the economics works due to lower fuel/maintenance costs.

Non-Tesla companies are making pretty much the same pitch in regards to battery busses, again targetting fleet managers who have the spreadsheets in place already to plan and manage this kind of expenditure.

Urban buses are very different and a more obvious target. Stop and go slower avg speed regular short routes with a home base to charge.

Much smaller batteries and taking advantage of regenerative braking.

It is an obvious use case for batteries right now.

How effective is regenerative breaking?

Oddly good.

My commute is ~25 miles one way. In my Leaf, going 65+ mph, I usually burn 25-35 miles off the charge. If I'm in stop-and-go traffic half the way I usually burn 10-15 miles for the same trip.

I've taken quite a few trips where I arrived at my destination with the same amount of battery as when I left. I've yet to arrive with more charge but maybe one day...

That’s probably due more to the aerodynamic drag of doing >65mph than it is the regen braking in stop-and-go traffic. Mileage efficiency takes a big drop in our Leaf above 60mph.

EDIT: as a side note, efficiency takes a big drop in your ICE vehicle, too, I just notice it more in the Leaf with its gee-whiz telemetry.

It depends a lot on how you're driving. Numbers as high as 70% have been published, but I believe that requires the deceleration profile to be ideal, and that might not be the most comfortable one for passengers.

For buses it is very effective, since they stop every few blocks, whether the stop signal is red or not. It also makes for a huge saving on brake repair and replacement, which you can imagine is a big expense for buses.

Also city buses usually drive under 200 miles a day and then sit overnight so you can have relatively small batteries. All in all, it is hard to think of a type of vehicle where battery power makes more economic sense, and gives you more advantages over ICE.

A relative is super gung ho for electric buses. The evangelist / champion at an energy company. His vacations are scheduled around various unveiling events, so he can get pics. Kinda reminds me of train enthusiasts.

Any way. Per what cousin tells me, I think short haul urban centric anything is ripe for electric vehicles. Delivery trucks, buses big and small, service vehicles. Maybe even tow trucks (wreckers).

And what's the cost of those busses plus charging infrastructure and the risk of new technology versus overhead power lines like what's deployed throughout much of San Francisco, for example?

There's at least one rural delivery man who bought a Tesla Model S and paid for it by using the mileage payments he gets for his job.

There's a specific tax deduction for commercial vehicles that cost more than $50000.

I think your price estimate for the battery isn't too far off. If you scoll down on the page they estimate annual fuel savings to be $200,000. They then mention a two year payback period. This seems to imply a sticker price of around $400K.

I am trying to figure out how they get 2 year payback.

"On a 100-mile route, the Tesla Semi will average $1.26 per mile when operating costs are factored in to $1.51 for diesel trucks."

That 25 cents a mile savings, average trucker does 45,000 miles a year, 100,000 on the top end for long haul. Even at 100k a year that's an 8 year payback right?

Based on the "With fewer systems to maintain..." precursor to that factoid, I imagine they're also factoring in repairs and maintenance. In the reveal event, Musk said e.g. you'd never have to replace brake pads, a drive train, the windshield, etc.

Also, I'm totally out of my element here (family does trucking but I don't) but 45K miles/year seems like a super low estimate for someone who drives full time. Taking a look at this thread [1], it seems unreliable per month, but people seem to be talking about doing 3K/week or 10-12K/month like it's nothing (as long as your employers have the hours to give).

http://www.truckingtruth.com/truckers-forum/Topic-1229/Page-...

I assumed their cost per mile included maintenance which is pretty standard to do.

To do 2 year payback would be 400k miles a year, which is impossible without nearly 24/7 driving, which could be possible with automation but unlikely they are figuring that.

Those truckers you linked are saying 10,000 a month is realistic without pushing it for long haul OTR so that 120k a year still at least 7 year payback.

The TCO includes the cost of the lease, so it already includes payback of the upfront cost. If you're not leasing it, your cost per mile without considering upfront cost is much better than even the TCO calculation shows, so you can "payback" relatively quickly. If you lease it, you can take advantage of the lower cost of operations immediately.

No, the "payback period" isn't the time to pay off the total cost of the vehicle. It's the time to pay off the difference between the Tesla and the competition.

Here's how you do the calculation:

- Diesel semi: $125k

- Tesla semi: $200k ($75k more expensive)

- Miles driven per year: 150,000 (~8 hours per day at 50mph. Rotating shifts mean these trucks don't take weekends.)

- Net savings per mile: $0.25

- Savings per year: $0.25 * 150,000 = $37,500

- Break-even vs. cost of diesel: $75,000 / $37,500 = 2 years

So after two years you have more money than if you'd bought a diesel semi. That's what it means.

The 500 mile version is 250k which is what I was looking at for long haul.

So if your doing short haul with the 300 mile range version and rotating shifts you can get 2 year payback, ok.

Your estimations are probably very far off.

The Roadster was announced with a 200kwh battery, which is twice the capacity of the best Model S. Yet the Roadster is much smaller, and the 0-60/quarter mile times indicate that it is much lighter.

So, we can conclude that Tesla is accounting for some real technology optimization in their batteries over the next 4 years, which I'm sure the Semi will see as well.

The Roadster is probably all battery, no reason to think its not 2000 lbs of battery and 1000-1500 lbs of car.

Is there anything to indicate lithium batteries will somehow get 60-70% lighter in 2 years?

Not sure how realistic the whole Tesla releases are. They are definitely inspirational. One thing we know for sure is they have a great prototyping/photoshop/After effects team

I have been wanting to know this as well. With both the roadster and the truck, the battery seems to be quite a bit more advanced than what we have seen previously. The car is smaller than a model 3 but has a battery that is more than twice the capacity of what they said was possible before.

It will be fascinating to find out what is actually behind these vehicles. On a pure specs basis, it sounds incredible.

Diesel trucks with sleepers are not cheap, brand new they cost upwards of $150,000. If Tesla's price point is $250-300k I think it would be fair.

What about the Supercharger network? Fewer highways make it logistically easier to plan for well-positioned charging stations so they can produce smaller batteries that have to be charged more frequently. And the Semi could always hook on a battery trailer for longer hauls.

I'm guessing a battery pack of 2019 will weigh about 60-70% what the old battery pack of Model S weighted per kWh.

See for instance Roadster's 200 kWh, which I'm pretty sure is not twice as heavy as that of the Model S.

I doubt this semi is intended for long-haul trucking. The range however is very tempting for short-haul operations like JIT hubs.

How do you deliver 1.6 MW, is the plan the same voltage as the supercharger (480V) or some HV system?