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Comment: Re:"An anonymous reader" (Score 2) 112

by voidptr (#47451607) Attached to: SpaceX Falcon 9 Rocket Blasts Off From Florida

There was only 1 loss on ascent and 1 loss on decent with too few flights to show if those single losses had a probability of greater than 1 in 500.

Columbia was doomed by the time it finished ascent, it just took until descent for the scope of the damage to become apparent. Arguably both losses in the shuttle program can be considered "on ascent".

Comment: Re:I wish them well (Score 2) 146

by voidptr (#47388155) Attached to: NASA Approves Production of Most Powerful Rocket Ever

I think it's more the fact that the whole program feels like it is being stitched together based on which existing technologies and contractors contribute to which congressional seats, rather than which technologies are really a good fit in the long term. As well as the fact that beyond a fairly nebulous manned astroid-capture mission, there doesn't seem to be any great plan or will to have a concrete goal for the booster in general. If Congress earmarked $50B over the next decade to put a research station on the Moon or Mars and insulated it from the year-to-year whims that always infect NASA's budget process it'd be one thing, but they aren't. They're trying to build a rocket and then hope two administrations from now it gets a mission funded.

On the technical side, any believe there's no place for solid motors on crewed flight anymore except to ensure campaign donations from Thiokol and United Space Boosters.

Second, while waiting for the new SSME derivative to get finalized and into production, they intend to fly the existing engine inventory. As one of the larger flown relics from the shuttle program, and with several dozen laying around, many of us would rather see them distributed to smaller museums that didn't get orbiters instead of splashed in the ocean. And as a result of the decision to use up the existing stock, the entire expendable stack is built around an engine that's was originally designed for reusability, with all the cost and engineering penalties that implies, and is ultimately too small for the job anyway. If you don't try to fly the existing SSME stock, something like a larger, more modern F1 derivative may start to make more sense, enabling a more powerful liquid first stage without having to bolt solids on the sides to get it off the pad.

Comment: Re:what happens if the chick get pregnant? (Score 2) 240

by voidptr (#44536629) Attached to: One-Way Ticket: Mars One Project Applicants Top 100,000

Fun fact: having a child on Earth also means inflicting an uncertain existence upon them including certain death. That fact doesn't appear to have stopped significant numbers of earthers from breeding either, even in conditions most of us wouldn't want to spend a day in let alone a lifetime.

Comment: Re:Efficient-market, inefficient-energy hypothesis (Score 1) 775

by voidptr (#44166081) Attached to: Electric Vehicles Might Not Benefit the Environment After All

By your theory, my Model S wins. The initial purchase price of a Model S is pretty middle of the pack to comparable cars in the full size luxury sedan class.

Similarly sized and spec'd ICE vehicles to the Model S get 20 - 25 MPG. At $3.50/gallon gas, that's 14c/mile.

The Model S gets about 3 miles / kWh. At 11.5c/kWh, that's 3.8c/mile.

Even if we assume a kWh from gasoline and a kWh from the wall have similar environmental impacts, and transmission costs/losses for both are properly reflected in the price at the meter, the Model S is three and a half times more efficient at turning the delivered energy into motion.

Comment: Re:Let's compare the two (Score 1) 559

by voidptr (#43880391) Attached to: No, the Tesla Model S Doesn't Pollute More Than an SUV

You're the one who started with the statement you could power a gasoline engine with a renewable clean energy source, namely Hydrogen.

You can't. Hydrogen isn't an energy source, because you can't refine hydrogen into a viable fuel using just hydrogen feedstock in an energy positive process. Hydrogen/Oxygen is at best another energy storage media, with cycle losses and storage requirements that are distinctly different but not theromdynamically unlike existing battery chemistries. There's nothing "clean" or "renewable" about burning hydrogen in an ICE engine in and of itself.

Comment: Re:Let's compare the two (Score 2) 559

by voidptr (#43878811) Attached to: No, the Tesla Model S Doesn't Pollute More Than an SUV

The point is, hydrogen isn't any more of a fuel than lithium in a battery is. They're both just energy storage media.

Gasoline is a fuel, because I can take a barrel of oil out of the ground, consume some of it to repay the energy used to pump it out, consume some of it to refine the remainder into gasoline, and end up getting more energy out of burning the rest than I had at the beginning of the process.

There's no above-unity mechanism to get free hydrogen into a motor vehicle, certainly not one that works on any commercial scale.

Comment: Re:Why the anti-electric car meme? (Score 1) 559

by voidptr (#43878737) Attached to: No, the Tesla Model S Doesn't Pollute More Than an SUV

You missed two more:

Third, the people who make their living off of pumping liquified dinosaur out of the ground, turning it into gasoline and selling it to consumers.

Fourth, traditional car dealers who are (a) terrified of a direct to consumer sales channel, and (b) terrified of the fact that without 4,500 moving components in the engine and transmission alone, electric cars don't need anywhere near the maintenance required of a gasoline car, and thus more opportunities to upsell even more "services" 4 times a year. Even things like brakes don't get used up much if you're using aggressive regen most of the time to slow down.

Comment: Re:Facts don't deter FUD (Score 1) 559

by voidptr (#43878649) Attached to: No, the Tesla Model S Doesn't Pollute More Than an SUV

The Model S competes in price to other cars in the $80k - $100k price range to start with, if you were going to spend that much on a car anyway it's not any more expensive. And over a 3 - 5 year period, it's cheaper once you factor in the difference in fuel costs.

As for batteries, they currently have an 8 year warranty. We're learning fairly fast that what kills smaller batteries fast is heat and high states of charge, which are far less of a concern in cars where you've got thermal management systems and capacity to keep the charge around 80% most of the time.

Gasoline cars can end up with pretty expensive repair costs once you pass the 8 year / 100,000 mile mark too as engine components start to wear out. Even changing $2 gaskets gets pretty pricey when it takes 10 hours of shop time to get to it and bolt everything back together again.

Comment: Re:Let's compare the two (Score 2) 559

by voidptr (#43878579) Attached to: No, the Tesla Model S Doesn't Pollute More Than an SUV

hydrogen is renewable.

Only by expending more energy to crack it off of whatever it was previously attached to than you'll get back by burning it again, at which point you may as well just shove those electrons into the battery on a Tesla anyway and save yourself the trouble of trying to transport diatomic hydrogen around.

Comment: Re:Electric cars are just not going to take off... (Score 2) 446

by voidptr (#43799225) Attached to: Tesla Motors Repays $465M Government Loan 9 Years Early

That's not exactly a scenario I or most other people do often enough to make it influence which car I buy. For the once a decade I need to get from NYC to LA in a day and a half, I can rent or take a plane.

Of course, the irony here is once the Supercharger network finishes building out along I-40, I may very well drive from coast to coast a few times, since the Superchargers are cheaper than airfare.

You can bring any calculator you like to the midterm, as long as it doesn't dim the lights when you turn it on. -- Hepler, Systems Design 182

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