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Comment: Re:Another market overlooked (Score 1) 159

by fnj (#49610041) Attached to: Tesla's Household Battery: Costs, Prices, and Tradeoffs

The outages that only last a couple of hours are nothing more than a nuisance. When it starts reaching a day or more, it becomes a goddam nightmare. Without the well pump, you have no running water. Without water, you cannot flush the toilet. The refrigerator contents start to spoil. In the winter you have no heat. Residual water in the pipes can burst.

I would be perfectly happy with just the essentials. Well pump, furnace, and refrigerator. A 2 kW source with enough surge for motor starts would be enough. Not sure if 7-10 kWh would be enough to cover 2-3 days. You can manage the well pump by planning your use for brief periods of running; it has a very low duty cycle most of the time anyway, even in normal use. You can manage the furnace to an extent by building up a lot of heat and then letting it coast down for hours. The one you can't really manage is the refrigerator. But overall, this looks promising. It would be a lot more practical than a generator where you have no natural gas hookup.

Right up until I learned it does not include an inverter. WTF? My eyes rolled up in my head and I groaned. Shit. How stupid can you get with your marketing? OK, you also need changeover provisions. So maybe this is the province of a specialized reseller. Until I hear from one of those and hear the bad news on the bottom line, I am utterly unimpressed.

Comment: Re:Price won't come down (Score 1) 159

by fnj (#49609951) Attached to: Tesla's Household Battery: Costs, Prices, and Tradeoffs

Likewise, lithium from seawater is not economical

Says who? About one screen above your message we are informed that getting enough lithium for a Tesla Model S from seawater would cost $500, compared to $150 when mined. Altering the Tesla price from $79,900 to $80,250 sure as hell wouldn't make the latter any more uneconomical than the former.

A cellphone battery is very roughly 1/10,000 of the pack in a Tesla. Adding 35 cents to the cost of a $300-$800 cellphone certainly wouldn't make it uneconomical.

Only a tiny part of the expense of a lithium ion battery is the cost of the lithium.

Comment: Re:Most electric cars are powered by burning coal (Score 1) 279

by fnj (#49587495) Attached to: New Study Suggests Flying Is Greener Than Driving

Electric traction motors are far more efficient than ICEs. That's why diesel locomotives don't actually connect the diesel engine to the wheels.

You are high. The diesel engine turns fuel into mechanical energy. If you change that mechanical energy into electricity and then back into mechanical energy, there is no way that could give you more efficiency than a simple mechanical transmission (which is typically well over 90% efficient). The reason for the electric transmission is flexibility. It does away with a big honking clutch and a multi-speed gearbox and gives you very smooth transition from standstill to forward motion.

Comment: Re:Masstransit is more energy efficient than perso (Score 1) 279

by fnj (#49587273) Attached to: New Study Suggests Flying Is Greener Than Driving

Any combustion engine running at surface conditions can do maybe 20 - 30% efficiency tops.

Better than that. There are internal combustion engines which reach 50% at sea level. The Wartsila-Sulzer RTA96-C 108,920 hp marine diesel exceeds 50%. Heck, even the TDI diesel engine in my 1999 Golf tops out at very close to 40%. The LM-2500+ gas turbine, a derivative of the CF6 which powers some 747s, adapted for shaft output, is over 39%.

Comment: Re:File manager without file, edit, view.. (Score 1) 440

by fnj (#49566533) Attached to: Debian 8 Jessie Released

Bullshit. They are HIDDEN. A menu bar that says "File", "Edit", and "View" in plain English or $LOCALIZED_LANGUAGE_OF_CHOICE is not hidden. Something that can only be accessed by knowing a secret location, or by finding a cryptic symbol and determining its purpose, is hidden.

SAA/CUA did not happen, and take over everywhere that mattered, because it was the product of a bunch of masturbating monkeys. It was the end product of research and insight of genuine experts in human interface, including Apple's HIG, and ultimately the innovators behind Xerox Star.

Comment: Re:WTF? It's Methanol (Score 1) 480

by fnj (#49566487) Attached to: Audi Creates "Fuel of the Future" Using Just Carbon Dioxide and Water

CO2 + H2O doesn't only make methanol. It makes hydrocarbon. Via various chemical processes, you can end up with whatever form(s) of hydrocarbon you want. Diesel fuel is good because (1) it is a very efficient and convenient energy storage medium and (2) a vast infrastructure of vehicles already use it. Methanol is an inefficient energy storage medium - quite apart from its toxicity.

Comment: Re:Based on the /. headline... (Score 1) 480

by fnj (#49566455) Attached to: Audi Creates "Fuel of the Future" Using Just Carbon Dioxide and Water

Since burning the fuel returns it back into CO2 and H2O, the amount of energy in the various bonds is irrelevant. All the energy you put in will come out again.

No; far from all of it; not in a useful form. A major part of it comes back, but neither the breakdown processes and the synthesis processes nor the engines consuming the end product are any where near 100% efficient.

Comment: Re:Not enough resourcees (Score 1) 480

by fnj (#49566409) Attached to: Audi Creates "Fuel of the Future" Using Just Carbon Dioxide and Water

The atmosphere has a mass of 5.15×10^18 kg. The concentration of CO2 is about 400 parts per million. That means there is 2.06x10^15 kg[*], or 2.06 trillion tonnes, of CO2 in the atmosphere. That works out to about 294 tonnes for every man, woman, and child in the world. There are also vast amounts dissolved in the oceans.

About 2.4 kg of CO2 is produced per litre of motor fuel burned; hence synthesizing motor fuel from CO2 requires about 2.4 kg of CO2 per litre. That means that the 2.06x10^15 kg of CO2 present in the atmosphere could generate over 8x10^14 litres of motor fuel, or more than ten thousand litres for every man, woman, and child in the world.

So around now, if you are a US driver, you are probably thinking that you do consume on the order of 500 gallons, or 2000 litres, of motor fuel per year, and you will note that there are other vehicles besides personal motor cars to be considered - trucks, planes, ships, etc.

But it seems to me you are utterly ignoring the overriding point. It is a giant closed system! Every kilogram of CO2 you process into fuel gets burned, and every single kg of CO2 you release from burning the fuel goes back into the atmosphere. And the overall loop is very nearly lossless. Sure, some very small fraction of the carbon liberated by combustion gets turned into CO or C particulates instead of CO2, but with modern pollution controls that fraction is very slight.

There are enormous logistical challenges to using the technique at full scale (including where to get the staggering amount of energy to run the synthesis), but running the atmosphere short of CO2 is not one of them.

[*] I spent a fair amount of time researching and could not readily determine whether the oft-quoted figure of 400 ppm is by volume or by mass. My math assumes that it is by mass. That actually leads to lower figures (pessimistic to my point) than if it is by volume, as it probably is. This is because CO2 is substantially higher density than air.

Comment: Re:I hope this never happens (Score 1) 649

by fnj (#49514667) Attached to: Automakers To Gearheads: Stop Repairing Cars

Any TDI owner who is not at the very least well-informed enough, and acquires a VAG-COM and some of the special tools, is in deep doo-doo. Even if you are on the good side of a very competent mechanic who will let you watch over his shoulder and check up progress, you still need to prime them on the fundamentals and ins-and-outs, because it would be totally prohibitive for them to do the learning themselves. Dealer repair shops are absolutely out of the question. Even if the cost were not prohibitive, there isn't a single one with TDI competence or who gives a single shit about your car.

Replacing the timing belt is a major, major operation involving dismounting the engine and supporting it, lining things up with special jigs and tools, and replacing every part in the path of the belt, including water pump, tensioner, and all rollers. Then you have to set the tension very precisely, not rotating the tensioner the wrong direction because it's opposite to that in a gas model, and finally nudging the heavy injection pump by thousandths of an inch to get the injection timing in spec, using the VAG-COM to check it. And if you're off the scale advanced or retarded when you begin the adjustment, it's a special adventure to find your way into the window so you can see anything at all on the VAG-COM. Or get it running at all.

If the timing belt ever strips teeth or skips more than a single tooth, you are in dire danger of doing several thousand dollars of damage to the engine, or totaling it.

Then there are the special cute things that can go wrong, like an injector that sticks open instead of pulsing properly. That will turn it into a blowtorch that will burn right through the top of the piston.

Comment: Re:The gold standard for fast, painless executions (Score 3, Interesting) 591

Entirely right about nitrogen asphyxia. There is nothing magic about nitrogen; you could as well use any other colorless, odorless inert gas, but nitrogen is the cheapest.

One correction, though. "Stopping the heart" per se is most definitely not painful. Ask anyone who has undergone true sudden complete cardiac arrest. You immediately feel a surreal calm as all that commotion in your chest you never really noticed until that moment, and the rush of blood through your head, stops. Within single digit seconds you feel crazy high. In 10-20 seconds you are out like a light. It may take 10 minutes for clinical irreversible death to eventuate, but after 10-20 seconds you are a sack of meat. We know from those whose heart spontaneously restarts, or are resuscitated before complete death or brain damage, that the experience after 10-20 seconds is nothing more than unconsciousness.

It's not so much that CO2, or cardiac arrest, "turns off" pain. It entirely sidesteps the strangling sensation caused by buildup of CO2. As others have noted, there is no physiologic sensation from lack of oxygen, but there is an almighty agony from CO2 buildup.

Make it myself? But I'm a physical organic chemist!

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