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Comment Re:Braking (Score 2, Informative) 144

Michael, you have it actually backwards. Electric cars gain energy by braking without friction. The rotating wheels of the car act as a generator, converting the car's kinetic energy into electricity with about 70% efficiency. That's why the friction brakes on my Tesla still squeak; because the regenerative deceleration is enough 98% of the time, and I rarely need to use the friction brakes.

Another nice feature of the Tesla is that the regen is triggered merely by lifting off the accelerator, so you can practically drive with one foot. It's also arguably safer, because deceleration starts immediately with no lag from moving your foot to the brake pedal.

Comment Re:How far in the winter... (Score 1) 457

Ok, one thing that always bothers me about these electric cars is the seeming ignorance surrounding the simple notion of how to provide climate comfort within the cabin.

HVAC takes a fairly small amount of energy relative to the car's overall usage. The electric drivetrain does produce a nontrivial amount of waste heat, which in theory could be used for cabin heating. Tesla chose not to do this, because it wasn't worth the added complexity. The Tesla at max acceleration uses 200kW, at highway cruising speed around 15kW, and the HVAC only about 2kW. And as for air conditioning, an ICE car doesn't have any obvious advantage over electric, that I can see. Most of the energy in the gasoline is lost as waste heat before it can be used to drive the AC compressor.

Common sense plays into this too. If you live in Minnesota in winter, don't drive in short sleeves. And if you live in Arizona, don't buy a black car.
The Internet

Malcolm Gladwell Challenges the Idea of "Free" 206

An anonymous reader brings us another bump on the bumpy road of Chris Anderson's new book, Free: The Future of a Radical Price, which we discussed a week ago. Now the Times (UK) is reporting on a dustup between Anderson and Malcolm Gladwell, author of The Tipping Point, Blink, and Outliers. Recently Gladwell reviewed, or rather deconstructed, Anderson's book in the New Yorker. Anderson has responded with a blog post that addresses some, but by no means all, of Gladwell's criticisms, and The Times is inclined to award the match to Gladwell on points. Although their reviewer didn't notice that Gladwell, in setting up the idea of "Free" as a straw man, omitted a critical half of Stewart Brand's seminal quote.

Comment Re:A requirement for the loan (Score 4, Insightful) 505

should have been a 25K car cost cap.

In the electric car industry, that's simply too big a jump to make all at once. If your ultimate goal is to produce 200,000 $25k cars a year, and the current state of the art is 2,000 $100k cars a year (the Tesla Roadster), then it's only reasonable to expect to produce 20,000 $50k cars (the Tesla Model S) as a stepping-stone. The market is there, and those early adopters will facilitate the eventual availability of the $25k mass-market car you're talking about. If you do the math, the "rich" purchasers of the Model S will be kicking in about one billion dollars a year towards this goal, double the government loan amount. So think before you knock 'em.
Portables

Submission + - IBM Working On 10x Battery Breakthrough (computerworld.com)

CWmike writes: "IBM said today that it is developing a next-generation rechargeable battery capable of storing 10 times more energy than today's top lithium-ion batteries. The new batteries could be used to power cars and store power for smart energy grids, it said. The company said it plans to discuss its work at its Almaden Institute 2009 conference on Aug. 26-27. 'High-density, scalable energy storage technologies are emerging as the greatest game-changer for this new era of renewable energy sources and smarter grids," said Sharon Nunes, vice president of IBM's Big Green Innovations organization. 'Today, the vast majority of the world's oil is burned for transportation. Energy sources such as wind and solar power fluctuate continuously. We believe the solution may lie in the development of an efficient, affordable energy storage network.'"

Comment Re:TFA Is slashdotted (Score 2, Interesting) 226

When thinking about dinosaurs' long necks, it's helpful to consider the possibility that the atmosphere was much thicker back then. So fluids could be drawn much higher without introducing vacuum problems, and it also explains how such huge insects and proto-birds (e.g. pterodactyls) could have flown there. Interesting stuff.

Comment Re:Units? (Score 3, Insightful) 426

The astounding thing to me is just how expensive this is... 6 billion for 1100MW is almost $6/nameplate watt.

From a related article:

The Sanmen Nuclear Power Plant will be built in three phases, with an investment of more than 40 billion yuan (5.88 billion U.S. dollars) injected in the first phase.
The first phase project will include two units each with a generating capacity of 1.25 million kw.

So it appears that the real cost is closer to 5.88 / (2 * 1.25) = $2.35 per watt. Still expensive, but not outlandish. I'm in the process of installing a 4kw grid of solar panels on my own roof for a cost (after subsidies/rebates) of $17k, so $4.25 / watt. For greener energy, I think the premium is worth it.

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