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Comment Re:Finally! (Score 1) 221

Because a compiler proves that it's not a toy by being self-hosting.

I'll bet that somebody will look to improve the performance in subsequent iterations. This is just the first revision, and it sounds like they did a direct translation from C to make sure that it would behave exactly the same.

Comment Re:Batteries (Score 1) 904

Batteries are the key. Everything about an electric car is infinitely better than a gasoline car, save the batteries. Electric motors are smaller, more powerful, have only a single moving part, require zero maintenance, and are a very mature, understood technology.

Tesla has been making incredible strides in getting every last bit of performance out of modern batteries. But compared to a gasoline tank, it still has a lot of problems
  • As you say, it still weighs a lot, adding significantly to the weight of a vehicle
  • It takes much longer to charge a battery than to fill a tank
  • There are limits to the rate at which power can be delivered to the motor. No such limit for gasoline. I will say, however, that Tesla appears to have completely solved this particular problem, at least at passenger car scale.
  • Batteries are much larger compared to a gasoline tank that provides the same range.
  • Battery capacity degrades over time. A gasoline tank's capacity does not.
  • Battery capacity is lower in cold weather. Gas tank capacity doesn't change appreciably with temperature. You can heat the battery to combat this, but then you're lowering effective capacity by using up the energy.

Full disclosure - I've owned a Nissan Leaf for the last three years. I love it and it works for many of my uses, but widespread EV adoption is going to require additional strides in battery technology.

Comment Re:Not even a link to the article (Score 5, Informative) 171

Link to the announcement on Tesla's website
And reproduced below:
  • 70 kWh rear drive Model S for $70k
  • 90 kWh battery pack option for $3k
  • 2.8 sec 0 to 60 mph upgrade to "Ludicrous Mode"

First, I should address something that might be on your mind, like: "Where the heck is the Model X and the Model 3!? You should really get on that." Don't worry, those remain our focus and good progress is being made on both. X is on track for first deliveries in two months and Model 3 in just over two years.

70 kWh for $70k
Now, on to the awesome news of today. The 70 kWh version of the Model S in the single motor version at $70k costs $5k less than the dual motor version, consistent with the price differential for the single and dual motor 85 kWh car. Importantly, enough options are now standard that you will have bought a great car even if you pick the base version.

In many countries, national and state/province purchase incentives for clean energy vehicles improve the price to some degree. In the US, for example, the price after incentives is usually around $60k. Also, not having to buy gasoline and needing less service for an electric car typically saves around $2k per year, which accumulates to $10k over the national average car ownership period of five years. This economic advantage is often overlooked when evaluating gasoline vs electric cars. Moreover, these savings are experienced immediately in your monthly cost of transportation if you lease or finance an electric car.

90 kWh Pack
New buyers now have the option of upgrading the pack energy from 85 to 90 kWh for $3k, which provides about 6% increased range. For example, this takes our current longest range model, the 85D, to almost 300 miles of highway range at 65mph.

Existing owners can also purchase the pack upgrade, but I wouldn't recommend doing so unless usage is on the edge of current range. On average, we expect to increase pack capacity by roughly 5% per year. Better to wait until you have more time on your existing pack and there is a larger accumulated pack energy difference.

Luuudicrous Mode
While working on our goal of making the power train last a million miles, we came up with the idea for an advanced smart fuse for the battery. Instead of a standard fuse that just melts past a certain amperage, requiring a big gap between the normal operating current and max current, we developed a fuse with its own electronics and a tiny lithium-ion battery. It constantly monitors current at the millisecond level and is pyro-actuated to cut power with extreme precision and certainty.

That was combined with upgrading the main pack contactor to use inconel (a high temperature space-grade superalloy) instead of steel, so that it remains springy under the heat of heavy current. The net result is that we can safely increase the max pack output from 1300 to 1500 Amps.

What this results in is a 10% improvement in the 0 to 60 mph time to 2.8 secs and a quarter mile time of 10.9 secs. Time to 155 mph is improved even more, resulting in a 20% reduction.

This option will cost $10k for new buyers. In appreciation of our existing P85D owners, the pack electronics upgrade needed for Ludicrous Mode will be offered for the next six months at only $5k plus installation labor.

It is important to note that the battery pack size upgrade and the pack electronics upgrade are almost entirely independent. The first is about energy, which affects range, and the second is about power, which affects acceleration.

There is of course only one thing beyond ludicrous, but that speed is reserved for the next generation Roadster in 4 years: maximum plaid.

— Elon

Comment Re:Crash Mitigation (Score 1) 549

After watching hours of Russian dash-cam videos on YouTube, I think the best thing that a self-driving (or any car) could do in a rear-end impact - at least for most scenarios) would be to stay on the brake hard. When a car is rear-ended, the most common thing to occur is for the driver's foot to leave the brake pedal, causing that car to continue forward and hit other things.

Comment Re:We the taxayer get screwed. (Score 1) 356

Tesla didn't replace 100,000 manufacturing jobs. They *added* 6,000 jobs that simply weren't there before. You're throwing up a very flawed strawman.

Furthermore, some company had to make those machines that Tesla operates. Tesla helped keep some of that company's employees employed.

Comment Re:We the taxayer get screwed. (Score 5, Informative) 356

OK, I bet there is an image of a crowd of thousands of men with their lunch pails all walking into their shift at the plant who then jump on the line and build cars.


At best it's a couple of dozen people working in the back office and some techs to walk around and monitor the automated plant.

Tesla has 6000 employees

But go ahead and keep undermining your arguments with such unnecessary hyperbole, mister Anonymous Coward.

Comment Possible Curriculum (Score 1) 175

Google CS First

I haven't taken a look at it yet myself (I just found out about it yesterday), but it sounds like it might be exactly what you're looking for.

All our materials are targeted at students in 4th - 8th grades (or between the ages of 9 - 14), and are free and easy to use.

Comment Re:low speed is the problem (Score 1) 823

I drive a Nissan Leaf. It has an exterior speaker that generates a noise when the car is travelling at less than 20mph (such as in a parking lot).

It doesn't matter. People just simply aren't paying attention, whether or not the car makes noise. They're too busy staring at their iphones.

A sine curve goes off to infinity, or at least the end of the blackboard. -- Prof. Steiner