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  • Tesla Motors (TSLA) Q4 2015 Results - Earnings Call Webcast  [View article]
    CPOs are in the finished goods inventory. So all sales of CPOs count there and likely what he referenced. Further, they do build demo cars and they do sell those. But in other parts of the call, they do mention that there is no channel and they build to order.
    Feb 10, 2016. 06:21 PM | 4 Likes Like |Link to Comment
  • Tesla Motors aims high with 2016 guidance  [View news story]
    Hmm... you might want to take some business courses. The gross margin is positive. Examine where the money is going.
    Feb 10, 2016. 05:00 PM | 12 Likes Like |Link to Comment
  • Tesla Motors preps for fight in Michigan  [View news story]
    74% coal, with the right scrubbers, is far better than burning gasoline and especially diesel.

    Of course, you point out the Tessum, et al. paper which conveniently neglects to factor in any gasoline production or distribution impacts. Gasoline magically appears in your gas tank according to their paper. It's another one of a string of papers that have garbage assumptions and therefore garbage outputs.
    Feb 1, 2016. 06:03 PM | 9 Likes Like |Link to Comment
  • Beware Tesla's Model 3 Mess  [View article]
    5% is reality? If you are an engineer, you know that 5% is some rounded number. How do you know it isn't 3.8%? Or 5.5%?

    As an engineer, don't you have to establish whether or not degradation is linear? Further, how is it measured?

    There are plenty of threads on owner forums on measuring range... and those that haven't done full balancing recently much lower reported range.

    Look at this paper on lifecycle of NCA cells written by Panasonic people:

    Look at the 2nd graph and you can conclude if the degradation is linear. Pay special attention to the slope of the line from cycle 0 to the first data point, and then the slopes to the other data points. Also note that this lifecycle test goes to 3,000 cycles... think of what that means for a car.

    The other major dataset to use is this one:

    It is also imperfect since it is a self selected group and not everyone has balanced their packs. So the reported range may be significantly lower than actuality.

    Also note that degradation is a function of charge cycles which translates to miles driven for the most part, not time. The expected lifetime of the cells exceeds 12 years...
    Jan 22, 2016. 02:58 PM | 3 Likes Like |Link to Comment
  • Beware Tesla's Model 3 Mess  [View article]

    The safety requirements of a passenger vehicle sold in the U.S. for on-street use is very different than in industrial applications.
    Jan 19, 2016. 11:46 AM | Likes Like |Link to Comment
  • Beware Tesla's Model 3 Mess  [View article]
    robiniv, you can believe whatever you want... but there is plenty of evidence that the contactors are in the pack and that is the primary source of battery pack failures. There are very few instances of this, and again, you can do your own homework on how often this happens. I already gave you a head start with the contactor part.

    You can also look up the typical reliability levels of high energy battery cells.

    Tesla cannot reasonably replace individual cells "one by one." Instead, they replace sheets if necessary. Your commentary seems to indicate that you've never actually even seen an open Model S pack which means you have done too little research for informed commentary.
    Jan 19, 2016. 11:42 AM | 5 Likes Like |Link to Comment
  • SpaceX booster landing fails, but comes close  [View news story]
    There are lots of forums, some with actual rocket engineers that discuss these issues.

    For the layman, there's the Wait Buy Why article on SpaceX:

    It's funny that people are now doubting SpaceX's ability to do this... I can understand a year or two or three ago, but now?

    Pretty much everything you might want to know about SpaceX's reusability is discussed here:
    Jan 19, 2016. 11:29 AM | 3 Likes Like |Link to Comment
  • SpaceX booster landing fails, but comes close  [View news story]
    They did land one.

    Also, SpaceX's explanation:

    Wait But Why article on SpaceX:

    Look to page 4 for the Falcon 9 explanations.
    Jan 19, 2016. 11:25 AM | 2 Likes Like |Link to Comment
  • Tesla Model S U.S. Sales: Peak Or No Peak  [View article]
    For a car delivered to the UK for instance, the car is built in Fremont and then disassembled into big pieces and takes a 2-3 week train ride to a port on the east coast. Then it waits for a ship. It is then shipped to Tilberg in the Netherlands where it is put through final assembly. Then it is shipped to the UK, where it is then shipped to a service center for delivery. Only when the customer picks up the car, paying the final total does the car count as a sale.

    Cars going to China, UK, Australia, and many parts of Europe have delivery times that are 4-14 weeks. As Tesla builds more cars, and delivers more cars to further away markets, the amount of finished good inventory naturally increases.

    It used to be that one production week's of finished goods inventory was around 300 vehicles. Now that one week's of production is well over 1000 vehicles and the deliver times have gone up with much higher use of rail and further away markets.
    Jan 18, 2016. 12:14 AM | 2 Likes Like |Link to Comment
  • Tesla: The Empty Threat Of The Chevy Bolt  [View article]

    A top 1% earner in the U.S. makes about $400,000 a year. You are saying that those making $200,000 a year, or the top 5% can't afford a $65,000 car?

    At $150,000 a year income, someone that saves appropriately can definitely afford a Model S responsibly. That's top 10%. That's over 11 million households in the U.S.
    Jan 16, 2016. 10:33 PM | 1 Like Like |Link to Comment
  • Beware Tesla's Model 3 Mess  [View article]
    Likely the largest cause of non-Ludicrous mode battery pack failures is a contactor failure. That is likely a slightly customized version of this $135 part:

    Tesla pulls the entire pack and repairs the pack offline, just like they do with drive units.
    Jan 14, 2016. 06:07 PM | 2 Likes Like |Link to Comment
  • Tesla's Model 3 Mess: The Aftermath  [View article]
    The only number I know of is the deferred revenue number given in the 10-K, the most recent for December, 2014. The problem is that it is a point in time number, not enough to know on a per car basis. It would be misleading to just divide the number by the number of cars, since each car is on a different schedule for deferred revenue.

    From the 10-K:

    "As of December 31, 2014, we had deferred $25.6 million related to access to our Supercharger network"

    Divided evenly, that $450 per vehicle at that time (57,000 or so cumulative Model S). Again, there are lots of caveats to that number. I assume the deferral is for something like 8 or 10 years. Some cars are already 1/4 or 1/5 through their deferral period.

    So about $500 per vehicle, but that is not just electricity. If that is done for 10 years, then yes, $50/vehicle/year for electricity + whatever access means.

    Note that this is different from the Supercharger installation costs.
    Jan 14, 2016. 02:58 PM | 1 Like Like |Link to Comment
  • Nevada Rolls Snake Eyes In The Tesla Gigafactory Casino  [View article]

    Yeah, for street cars, 5.3 C on a 60 kWh pack for 4 seconds is enough to exceed legal highway speeds in the U.S.. Steady cruising at 80 mph doesn't even come close to 1C. Model S probably needs all of 30 hp at 65 mph, maybe 45 hp at 80 mph - round to 35 kW. If you need to then hit the accelerator again, you do get 5C or so available again. But you don't need to keep using 5C on any legal street driving.

    Sure, for racing around a track it's not good enough, but for any not-losing-your-license driving on the street, its more than good enough. If Tesla was building a racing vehicle, they could choose a chemistry that has different optimizations. Tesla's cells are optimized primarily for specific energy and total energy capacity. It just so happens that when you put enough of them together to go 200-300 miles, you also get 400-600 hp for 3-5 second bursts.
    Jan 14, 2016. 02:16 PM | 1 Like Like |Link to Comment
  • Nevada Rolls Snake Eyes In The Tesla Gigafactory Casino  [View article]

    Tesla states that the curb weight of both the 90D and the 85D are the same. And the P85D and the P90D.

    For something definitive, you'll have to wait for one of the magazines to actually weigh the car. Car & Driver weighs the car and their weight for the 60 is far lower than published spec. It could be that the original 60 had a much higher weight and by the time Car & Driver tested the 60, the curb weight has dropped. Musk has said many times that they keep improving the car and referenced dropping weight during conference calls. They don't revise the official curb weight though.

    The cost of the pack and the relationship with the cells isn't that straight forward. You have to deal with the binning of the cells first... a bigger cell, all else being equal, will likely have a higher degree of waste or a lower percentage of cells hitting your highest bin. Further, it's actually easier to thermally manage the smaller cylindrical cells than the much bigger flat plate designs. The complexity of assembling the pack is mostly handled by robotics, so the issues of soldering are not likely as big of a deal. As you can see with the Bolt, a cooling plate only on the bottom of each edge of a cell is not the same level of cooling, which means they are hoping the chemistry can tolerate a much worse operating environment. Or just subject it to a much lower strain (less charging, less discharging). And suffer a higher range loss in the winter.
    Jan 14, 2016. 02:07 PM | 3 Likes Like |Link to Comment
  • Nevada Rolls Snake Eyes In The Tesla Gigafactory Casino  [View article]
    Don't have much time today...


    The numbers I have are all specific energy or gravimetric energy density given in Wh/kg.

    For a purpose built BEV, the challenge is putting as much battery capacity in for the weight. The volume with either the NCA or NCM chemistries are going to be a secondary concern. In other words, you run out of weight as a parameter before you run out of room in a purpose built BEV. For a conversion like the Ford Focus, well, it isn't a purpose built design so finding appropriate space was a problem. For a PHEV that has to share space with an ICE power plant and exhaust system, volumetric density is a big concern, so they tend to move to chemistries that optimize volumetric density and power density (kW/l). In a BEV, with a 60 kWh battery pack, these high energy chemistries provide more than enough power so that's not a concern either.

    The Kia Soul EV battery doesn't actually take 100 kW. They can plug into a nominal 100 kW CHAdeMO plug (500 volts, 200 amps) but with a much lower pack voltage, it's taking something more like 60-70 kW. Still an impressive charging c-rate for sure. The issue as it relates to Bolt is this:

    From the Car & Driver article, "What GM calls a cold plate in contact with the bottom of the cells circulates coolant to keep the batteries’ operating temperature in the desired range."

    One still has to remove the heat associated with high speed charging or it will cause more problems. At 90-120 kW, there's about 9-12 kWh of heat to move out of the system. The Bolt's cooling system is merely a plate at the bottom, not exactly a robust cooling system. Maybe it is sufficient, but there's a red flag right there in comparison to the cooling jackets that Tesla has used thus far. Certainly, we won't know for a while what effects this would have over the long term. Maybe that why they haven't aggressively moved to 120 kW charging which should be possible with that chemistry?

    Note from that same article, the CDa of the Bolt comes in at 8.05 square feet, or slightly worse than the Leaf's 7.8 and much worse than the Model S's 6.2. With a higher curb weight than the Leaf, the Bolt will likely have less highway efficiency than the Leaf. The Leaf is rated at 30 kWh/100 miles.
    Jan 14, 2016. 01:53 PM | 2 Likes Like |Link to Comment