On the other hand, uranium is a highly toxic heavy metal. Put enough of it on your tongue and you'll be in a very bad way, like the people who did the same with lead, mercury, cadmium....
The radiological properties of uranium are, as I understand it, vanishingly unimportant compared to the chemical toxicity.
The only things you get to vote for as a shareholder are the directors and shareholder initiatives;
Top management chooses the slate of directors and has great power to hold initiatives off the proxy ballot;
No matter how many shareholders strike a director off the proxy ballot, that director is still elected if s/he gets so much as a single vote. The only way for shareholders to get rid of a director is to wage a proxy fight, which involves printing and mailing their own proxies to shareholders. This is a very expensive proposal. Worse,
Shareholder initiatives are binding on no one, and the board and management are free to ignore them.
In theory, company management is responsible to shareholders. In practice, they are rarely responsible to anyone but themselves. (This message was brought to you nearly verbatim from that bastion of left-wing radical political theory, the editorial page of the Wall Street Journal.)
Just count me as someone who's seen enough engineering prototypes that foundered when scaled up to real, usable technologies. This has been the story of the battery powered electric car to a T.
Except that there's nothing new here. Battery-powered cars? They ruled the market a century ago, and it took some time and many improvements for combustion engines to displace them. Inverter drives for induction motors? In extremely broad use in industry. Batteries? Going into everything, reliable enough to be taken as a given if not for granted, and the appetite for more and more capacity is nearly insatiable.
The prototype has an extremely light chasis, and probably won't make side or front impact safety standards. Add more weight. How about air bags? Add more weight.
Use a stock steering column with an air bag: 15 pounds. Passenger-side airbag: 5 pounds, max. Front impact is probably better than Detroit iron, because there is no engine and the whole nose is available as crush space. Finally, side impact probably beats anything on the market, because the side rails are where the batteries are kept. Any side impact has to come through hundreds of pounds of batteries and its supporting structure before it can get to the occupants.
If you had read the acpropulsion.com site, you'd probably have discovered this. I've been following their news releases and brochures for a couple of years. Unfortunately the AC-150 system is far too expensive at its current low production volume for casual experimentation.
What happens to the batteries in a collision?
What happens to gasoline tanks in a collision? You can't equip them with fusible links or inertial disconnects.
Now we need Air Conditioning. And heat, since we don't get that for free from the engine.
Both the inverter and motor generate heat, and if you have enough batteries you can spend a few ounces on a resistance heater. (I'd direct you to the VW Vortex page on the one-liter concept car, except it appears to have been removed; here is the Google cache.) That said, the tzero is a balls-out sports car aimed at rich Californians. They don't need heat. Air conditioning is trivial, you just put a 3-phase electric compressor on it and the rest of the system is off the shelf (the Prius is going with electric A/C for 2004). Electric A/C is also coming to everything else, and has the advantage that you can get rid of the flexible hoses to the engine and the refrigerant leakage problems they cause.
A practical vehicle for today would be a "depletion mode" hybrid. If/when you ran out of battery power for propulsion and heat, you'd just fire up the sustainer and keep going. We could have done this ten years ago; we should certainly be doing it today.
This also doesn't answer the long term costs of battery replacement and life. I was glad to see that they were using a battery that lacks a memory effect, but the LiIon batteries in my laptop are still classified as hazardous waste.
So is the lead-acid battery under the hood of your car, but those have an extremely high recycling rate because you get the "core charge" back when you return one. If you are replacing 500 pounds at a time instead of 50, and doing it in a shop that does several a week, you can bet that your recycling rate is going to be close to 100%.
Finally, what powers a toy for the rich won't work for long haul trucking.
The best point you've made so far. But have you looked at what lots of trucks do all the time, especially in the east and west? They don't just fly down highways all day, they labor up hills at a snail's pace and then have to crawl down the other side on their Jake brakes, so they
Your claim that travel by car is polluting your air is not scientifically valid.
Teh vast majority of pollution in this coutry does not come from cars.
Define "pollution". For some pollutants, cars produce the vast majority of what's emitted. If you bothered to look at http://www.epa.gov/ttn/chief/trends/trends98/appen dix_a.pdf (which I found with a few minutes on the EPA website) you'll see that cars still emit a clear majority of all carbon monoxide emitted in the US (over 50 million short tons in 1998; most other categories top out at around a million tons or less). The total for "light duty gas vehicles and motorcycles" (27,039 thousand tons) and "light duty gas trucks" (18,726 thousand tons) is 45765 thousand tons, well over half the all-sources total of 89,454 thousand tons. When you add off-road engines and vehicles the fraction goes up to over two thirds.
Regarding other pollutants, on-road vehicles account for a shade under a third of all nitrogen oxide emissions too (albeit a large fraction of that comes from diesels), and so far as VOCs are concerned road vehicles are just about equal to all processes involving solvents (each being a bit under a third of the total) with most of that coming from cars and light trucks.
It amuses me to see someone whose favorite epithet is best applied to the face that greets them in the mirror in the morning.
The lack of perspicacity inherent in the Libertarian-anarchist school of thought never ceases to amaze me. There is an inherent contradiction between the ideas
that the utopia will be achieved when people will just go to court to recover damages for any act which hurts them, and
that this system will get rid of bans, regulations or taxes.
The hidden assumption with regard to clean air regulations is that emissions of particulates, oxides of sulfur, oxides of nitrogen, carbon monoxide, VOCs and the like are harmless. It's easy to prove that this assumption is false (ask anyone who lived through the "killer fog" in London, public health researchers looking at Mexico City, or just read the research on particulates and mortality rates); from this it follows that the advocates of positions which rely on it are deluded, lying, or victims of disinformation. Enough of them.
Given that the harm exists, the anarchist would go to court to obtain damages, perhaps with an injunction against future transgressions. The court would of course allow everyone affected to sue as a class, and recover damages or obtain an injunction as a group.
The immediate result would be to have a judicially-imposed pollution tax, pollution regulatory regime, or both. Rather than allow such important matters to be decided by judges, people would quickly get together and agree how much harm was acceptable and either mete out allowances for producing it or tax the emissions with the proceeds used to compensate the victims. This would immediately re-create the very government that the anarchists claim is inimical to human rights and progress... except that people would have (re)created it for the specific purpose of securing human rights and creating progress.
Do not confuse products and engineering prototypes
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You re-quoted:
But even if AC Propulsion claims the vehicle has efficiency equivalent to 70 mpg (and zero emissions), the tzero is, to a certain extent, an exercise in automotive fantasy. Its Spartan interior looks like a science project, in which most of the controls apart from the CD player are gadgets to monitor the battery and tiny 110-lb. motor.
The author of the article had either never driven anything but a fully-finished show car from a major manufacturer, or he was just interested in dissing the tzero. Computers, extra gauges and odd plumbing are expected in an engineering prototype, which the Li-ion tzero certainly is. You have exactly the same things in cars out of Detroit whenever they are trying something out.
Fuel cell cars are as heavy as normal vehicles, with the standard amenities. Put all of that back into your wundercar and it performs as poorly as all battery driven vehicles. Not to mention that the price will go up from the already ridiculous $200,000.
Oh, really? You're comparing hand-built vehicles... to what? the Geo Metro? A more apt comparison would be other very-low-production performance cars. How much does it cost to build something like a Shelby Cobra? Probably at least as much as the tzero, and I doubt that the original had A/C either. They certainly didn't build their whole drivetrain from scratch.
Unless there is something inherently expensive about the materials or processes involved (and there isn't), volume production would have the same effect on vehicles like the tzero (at least its drivetrain and storage systems) as it does on everything else. The performance is a simple matter of power/weight, which the tzero had in abundance even before its batteries were lightened by 450 pounds. Add that back in air conditioners and power windows and you'll still have one very quick car.
If you wish to claim otherwise, I'd love to see some reasoned argument from you. So far I've been quite disappointed.
I followed your links. The Honda link led me to a subscribers-only page, and the Edmunds link has few specifics and none on tank size. But the LLNL page has something you can sink teeth into.
Their Table 1 lists a volume of 28 gallons for the LH2 tank, or 62 gallons for the compressed H2 tank. Comparing against current Li-ion cells, I note that you'd be able to squeeze 50 of the 100 AH cells into the volume of the LH2 tank for an energy capacity of roughly 18 KWH; that's 90 miles for most electric vehicles. But the battery doesn't evaporate its stored energy, so it's more equivalent to the CH2 tank. 235 liters of cells would be roughly 112 cells, for energy storage of 40.3 KWH and a range of about 200 miles. The latter pack would weigh about 740 pounds, and unless you were going on long trips you would never have to stop to charge except at home.
At first blush hydrogen has a range advantage, but batteries can go into odd nooks and crannies where you can't stick hydrogen tanks. (Natural-gas vehicles have the same problem.) The best system might be a hybrid FCV, where run on batteries for most driving and only fill the liquid-hydrogen tank when you are going on a long trip. If you ran the tank dry on every leg (or burned off the hydrogen to recharge the batteries rather than letting it go to waste), you could take advantage of the strong points of both systems.
Unfortunately for hydrogen, that gallon-equivalent (119,000 BTU) of energy per kilogram comes at a density of 0.07 even for LH2; that's about 14 liters of volume for 3.8 gasoline-liters-equivalent of energy. A diesel sustainer engine running on biodiesel at 121,000 BTU/gallon and 40% thermal efficiency would get the same gallon-gasoline-equivalent of useful energy out of a mere 1.13 gallons of volume (compensating for 40% efficiency vs. 46%), so the 28 gallon LH2 tank could be replaced by an 8.5 gallon biodiesel tank. You'd have no evaporation problems to contend with or requirements to engineer a new fuel system, either; everything is off the shelf. Hydrogen just isn't very attractive as a motor fuel, which is why I think it is a distraction from the issues we should be addressing here and now.
Use the power to make hydrogen. Use said hydrogen to float zeplins and transport said hydrogen to other countries. Re-inflate with helium in storage tanks. Fly back, re-compress helium and reful with hydrogen. Repeat.
Why complicate things, when your blimp could just carry water for ballast on the trip out and dump it for the trip back?
For extra credit you could make the ballast something else that embodies energy, like magnesium metal (easily recovered from seawater), or liquid methane or methanol (easily made with hydrogen if you can also obtain CO2).
Which we do using oil for a net loss in energy. We could not produce the volume of biomass from agriculture that we do without that oil energy.
A feat made possible with nitrogen fertilizers produced using... hydrogen reformed from fossil fuels. A fact not lost on me in the slightest.
But I wonder if you have looked at the latest research: hydrogen from algae (press release here). At 10% efficiency, or even 5%, the energy output of even a small pond is substantial. Maybe the really clever could find a way to make this work in plastic bladders on rooftops. It would certainly be cheap, and if a farmer could "grow" his own tractor fuel, nitrogen fertilizer and other needs via aquaculture, it would remove many of the limits to sustainability which plague our current modus operandi.
Right now, the batteries that would be used in electric cars are far too heavy, as far as energy/mass goes.
Whereas hydrogen fuel-cell cars have an Achilles' heel of their own: hydrogen storage is far too bulky. The vehicles demoed recently have ranges well under 100 miles.
And, as batteries get lighter they get really expensive.
Unless there is something very expensive about the raw materials or really hard about the fabrication, you'll see a rapid drop in cost as the volume increases. We've been seeing this with silicon chips, solar cells and Li-ion batteries for years, and I doubt that the trend is going to stop. Every decrement in price brings more uses within reach, which further boosts the volume and decreases the price. It's a grand virtuous cycle.
Is there another that actually burns H2 for something akin to internal combustion?
Sure. It's called... an internal combustion engine. The problem is that your bulky hydrogen tankage will only take your vehicle 1/2 to 1/3 as far if it's feeding a 20-30% efficient combustion engine instead of a 60% efficient fuel cell, and if a vehicle with a range of 60 miles is barely practical a vehicle limited to 20 miles between fuelings is downright ludicrous.
Yes, I am an engineer.
Do not say it is impossible to the person doing it
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I found this:
Batteries just don't cut it, and there are zero developments on the horizon that can improve them in the ways needed for vehicular use.
... particularly ironic in the light of this thread from two days ago. And if you look at the specs on even the current batteries, you'll see that their fastest rated charging rate is 3C; that means you could quick-charge your pack from 20% to 80% in 12 minutes. That is at least as fast as most hydrogen-filling schemes are supposed to be, and nearly as fast as pumping your car full of gas. If the car achieves 300 miles on a full charge, that 60% would get you about 180 miles or 2.4 hours at 75 MPH.
None of the fuel-cell vehicles being demonstrated these days has a range that anyone would consider practical; meanwhile, a private operation with an EPRI contract shows something that blows them all out of the water, at a fraction of the price. Fuel cells have their place in stationary generation where you can use the waste heat and bulk of the fuel is not a factor; for vehicles over the next 20 years, my money is on batteries for the practical ZEV.
Don't worry--when the costs have come down enough, China, India, Europe, Japan, and other nations will do that, no matter how cushy the relationship between the US government and large US aerospace contractors may be.
Europe won't do it. Europe's creative drive is spent, gone, kaput. Japan can't even find a launch site that lets them get birds into orbit on schedule, and is experiencing an inverted population pyramid with all the lack of dynamism that implies. So's Europe, for that matter.
The USA is the country that ought to have been out there years, nay, decades ago, and it worries me that we may have changed places with China in the flow of history. Once China was rich and powerful, and sent trading and exploration fleets as far as the Horn of Africa. But court politics caused the downfall of the advocates of expansion, and the fleets were recalled and destroyed, the records burned. Just a few years later Europe's explorers hit the areas from which the Chinese had withdrawn. The rest is, as they say, history. Without the short-sightedness of the Confucian overlords, huge tracts of the world might never have been exposed to Enlightenment thought and the United States might not exist.
Now the Chinese have gone into orbit, and the attitude of America is yawn, been there, done that. There is no call to pick up the job left unfinished, to refuse to cede the high ground to the forces inimical to progress. And if you think China's government is friendly to human rights, freedom of thought or anything that threatens their grip, take a look around once in a while; google for "Free Tibet".
It doesn't worry me that they'll go. It worries me that they'll use it as a way to expand the prestige of their dictatorship and extend their illegitimate powers. That would be good for nobody except the dictators.
And all because our the political establishment saw space more as pork barrel to be exploited than an essential strategy, and public was too apathetic or cynical to demand more from them. Doesn't that just suck?
Until people actually demonstrate cheap technologies for lifting people into orbit and keeping them there, we have to go by current prices, and they are hugely expensive.
Q: Who has the most to lose from the demonstration of cheap technologies for launching people and letting them work in space?
A: The people now collecting billions from the expensive contracts to build and maintain the current systems.
Unless we do something to upset the apple cart, we will be stuck with a couple people in orbit doing nothing and going nowhere. I do not find this an acceptable state of affairs. The people now running the show are some of the biggest obstacles to progress, and they have to be shoved out of the way.
There is an easy solution to that: don't send humans into space for the time being.
I would revise that to, "Do not send humans into space to stay on the ISS". This amounts to the same thing in the short term, because replacing the ISS with a station which has artificial gravity will take time.
Eventually, we can build spacecraft that are large enough to generate "artificial gravity" by rotation.
"Eventually"? If I'm not mistaken, a Gemini capsule performed a rendezvous with an Agena rocket, pulled a tether out from it and spun the pair up to provide artificial gravity. This was something like FORTY YEARS AGO.
The Livermore "community space suit" station was designed as an alterative to this (more usable volume AND artificial gravity), and it would have launched in ONE shot of a Titan. Rather than adopt it as a way to get the job done cheaper, the various functionaries on the gravy train quashed it rather than spoil the tens of years and billions of dollars of contracts for the non-gravity-capable ISS. This speaks volumes.
Until then, robots and teleoperators are far cheaper and more effective for space exploration and scientific missions into space.
They're usually far cheaper... for the things they can do. But when you compare even the most sophisticated surface rovers with the capabilities of a human with a rock hammer, it's obvious that really serious investigations are going to require people on the scene. It's the avowed goal of these "life sciences" investigations to get us there, and we should insist that the boondoggles and pork-barrelling be put behind that rather than ahead.
Do planes carry oxygen or are they feeding the pilots pressurised air?
Depends on the plane, but even pressurized aircraft feed their systems on outside air and pilot oxygen systems are usually supplemental rather than 100%. Low-altitude aircraft don't bother with pressurization or oxygen.
If either one took a slug of combustible mixture into the cabin and someone had a cigarette, kiss the craft goodbye.
If they had emergency oxygen, they might have to be quick witted. I don't think they cover this in pilot training.
You're right, they don't. On the other hand, flight through clouds of toxic gas is not a hazard which affects many people. I'm not sure how fast methane would poison you anyway; if it would take longer to render the pilot(s) incapable of controlling the aircraft than it would take to glide out of the cloud, then it's survivable regardless.
No idea what ignition would do. Most aircraft's flying speed is faster than the normal flame speed, so unless the cloud was well-mixed to form a combustible mixture throughout it might not do very much except burn at the edges (which one would rapidly glide away from).
Sorry, but they do. They use a diode which converts some of the input energy to its second harmonic, which is re-radiated (when the tag is energized, and if the diode is not blown to deactivate the tag).
The amount of RFID equipment that it would take to cover every inch of a library is pretty substantial, and that equipment is damn expensive. We have some of it to mess around with there, and you have been inches away to get it to react.
Most people don't walk around libraries reading books, they sit down at a chair or table. If you can read the RFID tag with a coil you walk past, you can read it with a coil built into the chair. It would be trivial to read the tags of all the books on a table using a coil wound around the periphery of the table; I could do that to the typical table in a couple of days using no tools more sophisticated than a router (woodworking tool, not network device).
With the paranoia going around the library systems these days, I seriously doubt they'll be putting this type of equipment in to do that sort of detection. The chances that some government agency would do something like that are even smaller, since the library would scream bloody murder.
Function creep. They get the libraries to do it for convenience of tracking and shelving, and design the system so they can siphon off the data they want without attracting any attention. If you don't think so, consider the controversy over Diebold voting machines and the political affiliations of the principals of the company.
If you would read Schneier, you'd know that the only way to make a secure system is to design security into it from square one. You cannot tack security onto it. If we design our library checkout/inventory systems in a way which makes it easy to abuse them for surveillance and thought-policing, rest assured that someone, somewhere will do that.
Time is money sure, but does the time it take to tag this many books and the cost, really out way the time saved locating books that get lost in simple tracking?
Do you have any idea how much time they could save by being able to wave a wand past the shelf and immediately register all of the mis-shelved books? Think about that; it's a neat-freaks wet dream.
Also, how do you deactivate a passive device?
You mean you've never seen it done to the induction tags they use today? You hit it with a high-power jolt that destroys one of the components. (A hex bolt is a passive device too, but a big enough wrench...)
I thought the general consensus of librarians was that the USA PATRIOT Act was wrong. Why would they further promote it?
Because the left hand does not know what the right hand is doing. As "nerds" we are familiar with function creep, but librarians (especially at the policy-setting level) do not necessarily even know what that means.
What the fuck do RFID tags on books have to do with the PATRIOT Act, specifically?
They make it feasible for a sufficiently savvy agency to see who is taking what books out of the library by scanning at a distance, or even seeing who had what book in their hands at the tables inside. If you think that the dropped ceilings in most libraries don't have enough space to hide all kinds of radio gear and directional antennas, you don't know enough E&M.
These things get their power through inductance, do they not? So what's wrong with, say, using a small amount of inducted power to read the data they contain, but a larget amount will induce enough power to pop an incorporated fuse?
That's fine if the tag is part of something that belongs to you. What do you do if the tag is part of something that belongs to the library? Are you going to "pop" the tag (with what?) before you walk out the door with the book, and then pay the library to re-enter the book in their inventory (which is probably indexed by the tag ID number) when you return it?
If I had to guess -- 56K dialup modems are an end of the line technology. There won't be any next generation, and the people who need one need one so there's no Moore's Law and no competition driving down prices.
As someone who's sitting here looking at a 56 K external modem, and who also knows that there is about as much electronic stuff in it as in your $5 Rat Shack telephone, I'll disagree with you.
This is not legacy gear. There are plenty of people out there who still don't have computers, or are replacing older modems (the same way people are replacing older phones with the $5 Rat Shack model). The market is not exploding, but there are going to be steady sales for years. This is not a legacy market, it is ready to be a commodity market.
Given that it is a commodity-market-in-waiting, anyone who comes to market with a good product at $35 is going to carve out a big chunk of USR's $70 modem market. Ditto the company that hits the $20 price mark. Eventually the reality of low sales will prevent the kind of radical margin shaving that characterizes RAM chips, but there's plenty of room to move down.
The other reality is that electronic gear lasts a reasonably long time. If it truly is a legacy technology and not improving, the new gear will face stiff competition from its older models. This means the price is likely to come down, at least for the careful shopper.
That is the key question. If all you have is one race to count, it's easy to use paper: you can even divide the ballots into piles and have them counted independently and in parallel, even re-counted by multiple counters.
The problem is when you have a typical US ballot with city, county, school board, tax levies, initiatives, state and national races all being decided on one election day and one huge ballot (which is different from precinct to precinct because the district boundary lines don't all coincide). Just printing those things is a huge burden, and counting them with anything other than optical mark-sense gear is a task of Floridian scope. Unless you want to issue voters umpty-ump different ballots for the various races, you're stuck with a mess. Using umpty-ump different ballots is a different kind of mess, just a little easier to count by hand.
I found something on the use of car alternators as stepper motors (used at least once to drive a router as a "print head") at http://www.tinaja.com/glib/resbn46.pdf.
But it's got no details. (The bizarre porn sites showing up in the results of my search have to be seen to be believed.) The stuff at tinaja.com seems to be the most relevant; if you are trying to sling a big print head over a large surface and you aren't too concerned with sub-millimeter accuracy, that's probably your best bet.
in that they take up far less parking space per ride. Even if the cab is only carrying one rider at a time, it is carrying far more riders on an average day and it still takes only one space at the taxi stand.
When the day's activities are over, the driver of the car has to get to the car and get it out of there. The person who rode the cab in can just as easily take the bus out.
Don't get me wrong, I'm a dedicated driver and I can barely get along without a car. But I'm not about to sell buses and cabs short on their strong points, and parking and road congestion are darn good ones in their favor.
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The radiological properties of uranium are, as I understand it, vanishingly unimportant compared to the chemical toxicity.
- The only things you get to vote for as a shareholder are the directors and shareholder initiatives;
- Top management chooses the slate of directors and has great power to hold initiatives off the proxy ballot;
- No matter how many shareholders strike a director off the proxy ballot, that director is still elected if s/he gets so much as a single vote. The only way for shareholders to get rid of a director is to wage a proxy fight, which involves printing and mailing their own proxies to shareholders. This is a very expensive proposal. Worse,
- Shareholder initiatives are binding on no one, and the board and management are free to ignore them.
In theory, company management is responsible to shareholders. In practice, they are rarely responsible to anyone but themselves. (This message was brought to you nearly verbatim from that bastion of left-wing radical political theory, the editorial page of the Wall Street Journal.)Except that there's nothing new here. Battery-powered cars? They ruled the market a century ago, and it took some time and many improvements for combustion engines to displace them. Inverter drives for induction motors? In extremely broad use in industry. Batteries? Going into everything, reliable enough to be taken as a given if not for granted, and the appetite for more and more capacity is nearly insatiable.
Use a stock steering column with an air bag: 15 pounds. Passenger-side airbag: 5 pounds, max. Front impact is probably better than Detroit iron, because there is no engine and the whole nose is available as crush space. Finally, side impact probably beats anything on the market, because the side rails are where the batteries are kept. Any side impact has to come through hundreds of pounds of batteries and its supporting structure before it can get to the occupants.
If you had read the acpropulsion.com site, you'd probably have discovered this. I've been following their news releases and brochures for a couple of years. Unfortunately the AC-150 system is far too expensive at its current low production volume for casual experimentation.
What happens to gasoline tanks in a collision? You can't equip them with fusible links or inertial disconnects.
Both the inverter and motor generate heat, and if you have enough batteries you can spend a few ounces on a resistance heater. (I'd direct you to the VW Vortex page on the one-liter concept car, except it appears to have been removed; here is the Google cache.) That said, the tzero is a balls-out sports car aimed at rich Californians. They don't need heat. Air conditioning is trivial, you just put a 3-phase electric compressor on it and the rest of the system is off the shelf (the Prius is going with electric A/C for 2004). Electric A/C is also coming to everything else, and has the advantage that you can get rid of the flexible hoses to the engine and the refrigerant leakage problems they cause.
A practical vehicle for today would be a "depletion mode" hybrid. If/when you ran out of battery power for propulsion and heat, you'd just fire up the sustainer and keep going. We could have done this ten years ago; we should certainly be doing it today.
So is the lead-acid battery under the hood of your car, but those have an extremely high recycling rate because you get the "core charge" back when you return one. If you are replacing 500 pounds at a time instead of 50, and doing it in a shop that does several a week, you can bet that your recycling rate is going to be close to 100%.
The best point you've made so far. But have you looked at what lots of trucks do all the time, especially in the east and west? They don't just fly down highways all day, they labor up hills at a snail's pace and then have to crawl down the other side on their Jake brakes, so they
Regarding other pollutants, on-road vehicles account for a shade under a third of all nitrogen oxide emissions too (albeit a large fraction of that comes from diesels), and so far as VOCs are concerned road vehicles are just about equal to all processes involving solvents (each being a bit under a third of the total) with most of that coming from cars and light trucks.
It amuses me to see someone whose favorite epithet is best applied to the face that greets them in the mirror in the morning.
- that the utopia will be achieved when people will just go to court to recover damages for any act which hurts them, and
- that this system will get rid of bans, regulations or taxes.
The hidden assumption with regard to clean air regulations is that emissions of particulates, oxides of sulfur, oxides of nitrogen, carbon monoxide, VOCs and the like are harmless. It's easy to prove that this assumption is false (ask anyone who lived through the "killer fog" in London, public health researchers looking at Mexico City, or just read the research on particulates and mortality rates); from this it follows that the advocates of positions which rely on it are deluded, lying, or victims of disinformation. Enough of them.Given that the harm exists, the anarchist would go to court to obtain damages, perhaps with an injunction against future transgressions. The court would of course allow everyone affected to sue as a class, and recover damages or obtain an injunction as a group.
The immediate result would be to have a judicially-imposed pollution tax, pollution regulatory regime, or both. Rather than allow such important matters to be decided by judges, people would quickly get together and agree how much harm was acceptable and either mete out allowances for producing it or tax the emissions with the proceeds used to compensate the victims. This would immediately re-create the very government that the anarchists claim is inimical to human rights and progress... except that people would have (re)created it for the specific purpose of securing human rights and creating progress.
Unless there is something inherently expensive about the materials or processes involved (and there isn't), volume production would have the same effect on vehicles like the tzero (at least its drivetrain and storage systems) as it does on everything else. The performance is a simple matter of power/weight, which the tzero had in abundance even before its batteries were lightened by 450 pounds. Add that back in air conditioners and power windows and you'll still have one very quick car.
If you wish to claim otherwise, I'd love to see some reasoned argument from you. So far I've been quite disappointed.
Their Table 1 lists a volume of 28 gallons for the LH2 tank, or 62 gallons for the compressed H2 tank. Comparing against current Li-ion cells, I note that you'd be able to squeeze 50 of the 100 AH cells into the volume of the LH2 tank for an energy capacity of roughly 18 KWH; that's 90 miles for most electric vehicles. But the battery doesn't evaporate its stored energy, so it's more equivalent to the CH2 tank. 235 liters of cells would be roughly 112 cells, for energy storage of 40.3 KWH and a range of about 200 miles. The latter pack would weigh about 740 pounds, and unless you were going on long trips you would never have to stop to charge except at home.
At first blush hydrogen has a range advantage, but batteries can go into odd nooks and crannies where you can't stick hydrogen tanks. (Natural-gas vehicles have the same problem.) The best system might be a hybrid FCV, where run on batteries for most driving and only fill the liquid-hydrogen tank when you are going on a long trip. If you ran the tank dry on every leg (or burned off the hydrogen to recharge the batteries rather than letting it go to waste), you could take advantage of the strong points of both systems.
Unfortunately for hydrogen, that gallon-equivalent (119,000 BTU) of energy per kilogram comes at a density of 0.07 even for LH2; that's about 14 liters of volume for 3.8 gasoline-liters-equivalent of energy. A diesel sustainer engine running on biodiesel at 121,000 BTU/gallon and 40% thermal efficiency would get the same gallon-gasoline-equivalent of useful energy out of a mere 1.13 gallons of volume (compensating for 40% efficiency vs. 46%), so the 28 gallon LH2 tank could be replaced by an 8.5 gallon biodiesel tank. You'd have no evaporation problems to contend with or requirements to engineer a new fuel system, either; everything is off the shelf. Hydrogen just isn't very attractive as a motor fuel, which is why I think it is a distraction from the issues we should be addressing here and now.
For extra credit you could make the ballast something else that embodies energy, like magnesium metal (easily recovered from seawater), or liquid methane or methanol (easily made with hydrogen if you can also obtain CO2).
But I wonder if you have looked at the latest research: hydrogen from algae (press release here). At 10% efficiency, or even 5%, the energy output of even a small pond is substantial. Maybe the really clever could find a way to make this work in plastic bladders on rooftops. It would certainly be cheap, and if a farmer could "grow" his own tractor fuel, nitrogen fertilizer and other needs via aquaculture, it would remove many of the limits to sustainability which plague our current modus operandi.
Yes, I am an engineer.
None of the fuel-cell vehicles being demonstrated these days has a range that anyone would consider practical; meanwhile, a private operation with an EPRI contract shows something that blows them all out of the water, at a fraction of the price. Fuel cells have their place in stationary generation where you can use the waste heat and bulk of the fuel is not a factor; for vehicles over the next 20 years, my money is on batteries for the practical ZEV.
The USA is the country that ought to have been out there years, nay, decades ago, and it worries me that we may have changed places with China in the flow of history. Once China was rich and powerful, and sent trading and exploration fleets as far as the Horn of Africa. But court politics caused the downfall of the advocates of expansion, and the fleets were recalled and destroyed, the records burned. Just a few years later Europe's explorers hit the areas from which the Chinese had withdrawn. The rest is, as they say, history. Without the short-sightedness of the Confucian overlords, huge tracts of the world might never have been exposed to Enlightenment thought and the United States might not exist.
Now the Chinese have gone into orbit, and the attitude of America is yawn, been there, done that. There is no call to pick up the job left unfinished, to refuse to cede the high ground to the forces inimical to progress. And if you think China's government is friendly to human rights, freedom of thought or anything that threatens their grip, take a look around once in a while; google for "Free Tibet".
It doesn't worry me that they'll go. It worries me that they'll use it as a way to expand the prestige of their dictatorship and extend their illegitimate powers. That would be good for nobody except the dictators.
And all because our the political establishment saw space more as pork barrel to be exploited than an essential strategy, and public was too apathetic or cynical to demand more from them. Doesn't that just suck?
A: The people now collecting billions from the expensive contracts to build and maintain the current systems.
Unless we do something to upset the apple cart, we will be stuck with a couple people in orbit doing nothing and going nowhere. I do not find this an acceptable state of affairs. The people now running the show are some of the biggest obstacles to progress, and they have to be shoved out of the way.
The Livermore "community space suit" station was designed as an alterative to this (more usable volume AND artificial gravity), and it would have launched in ONE shot of a Titan. Rather than adopt it as a way to get the job done cheaper, the various functionaries on the gravy train quashed it rather than spoil the tens of years and billions of dollars of contracts for the non-gravity-capable ISS. This speaks volumes.
They're usually far cheaper... for the things they can do. But when you compare even the most sophisticated surface rovers with the capabilities of a human with a rock hammer, it's obvious that really serious investigations are going to require people on the scene. It's the avowed goal of these "life sciences" investigations to get us there, and we should insist that the boondoggles and pork-barrelling be put behind that rather than ahead.If either one took a slug of combustible mixture into the cabin and someone had a cigarette, kiss the craft goodbye.
You're right, they don't. On the other hand, flight through clouds of toxic gas is not a hazard which affects many people. I'm not sure how fast methane would poison you anyway; if it would take longer to render the pilot(s) incapable of controlling the aircraft than it would take to glide out of the cloud, then it's survivable regardless.No idea what ignition would do. Most aircraft's flying speed is faster than the normal flame speed, so unless the cloud was well-mixed to form a combustible mixture throughout it might not do very much except burn at the edges (which one would rapidly glide away from).
If you would read Schneier, you'd know that the only way to make a secure system is to design security into it from square one. You cannot tack security onto it. If we design our library checkout/inventory systems in a way which makes it easy to abuse them for surveillance and thought-policing, rest assured that someone, somewhere will do that.
And quoth the first responder:
They make it feasible for a sufficiently savvy agency to see who is taking what books out of the library by scanning at a distance, or even seeing who had what book in their hands at the tables inside. If you think that the dropped ceilings in most libraries don't have enough space to hide all kinds of radio gear and directional antennas, you don't know enough E&M.Aye, there's the rub.
- This is not legacy gear. There are plenty of people out there who still don't have computers, or are replacing older modems (the same way people are replacing older phones with the $5 Rat Shack model). The market is not exploding, but there are going to be steady sales for years. This is not a legacy market, it is ready to be a commodity market.
- Given that it is a commodity-market-in-waiting, anyone who comes to market with a good product at $35 is going to carve out a big chunk of USR's $70 modem market. Ditto the company that hits the $20 price mark. Eventually the reality of low sales will prevent the kind of radical margin shaving that characterizes RAM chips, but there's plenty of room to move down.
The other reality is that electronic gear lasts a reasonably long time. If it truly is a legacy technology and not improving, the new gear will face stiff competition from its older models. This means the price is likely to come down, at least for the careful shopper.The problem is when you have a typical US ballot with city, county, school board, tax levies, initiatives, state and national races all being decided on one election day and one huge ballot (which is different from precinct to precinct because the district boundary lines don't all coincide). Just printing those things is a huge burden, and counting them with anything other than optical mark-sense gear is a task of Floridian scope. Unless you want to issue voters umpty-ump different ballots for the various races, you're stuck with a mess. Using umpty-ump different ballots is a different kind of mess, just a little easier to count by hand.
I found something on the use of car alternators as stepper motors (used at least once to drive a router as a "print head") at http://www.tinaja.com/glib/resbn46.pdf. But it's got no details. (The bizarre porn sites showing up in the results of my search have to be seen to be believed.) The stuff at tinaja.com seems to be the most relevant; if you are trying to sling a big print head over a large surface and you aren't too concerned with sub-millimeter accuracy, that's probably your best bet.
When the day's activities are over, the driver of the car has to get to the car and get it out of there. The person who rode the cab in can just as easily take the bus out.
Don't get me wrong, I'm a dedicated driver and I can barely get along without a car. But I'm not about to sell buses and cabs short on their strong points, and parking and road congestion are darn good ones in their favor.
I admit it does look normal next to a Ford Excretion or a Dodge Durigible.