h a l f b a k e r yRecalculations place it at 0.4999.
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a wide belt made of copper transfers the heat to a peltier which
removes a small amount of heat bringing it only 1 degree down,
with another peltier bringing that down by only 1 degree etc.
Thus you get failsafe cooling for car motors in hot countries vs the
water cooling and air conditioners
that break down constantly in
my country, with stopped cars all along the road on hot days
because of missing water.
Look Ma! No radiators.
https://www.youtube...watch?v=iehzjEhM1DU (subtitles) 41 min. [2 fries shy of a happy meal, Nov 16 2021]
Hydrogen from microbes
https://www.energy....-biomass-conversion There are other ways to get hydrogen. [neutrinos_shadow, Nov 17 2021]
[link]
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Sort of off topic but you might find it interesting [pashute], there is a fellow in Greece who uses solar panels to run a dehumidifier to extract pure water from the air. Another solar panel for electrolysis splitting the water into hydrogen and oxygen, and yet another solar panel to compress the hydrogen into liquid. He has rigged up small tanks which spray hydrogen directly into the piston chambers of every one of the gas engines on his farm to equal the combustion of gasoline, (there is enough free oxygen in the piston chamber to make the hydrogen flammable), and since the expanding gas is extremely cold it has the side effect of cooling the engine so that it runs colder than when sitting idle and he's stripped out every radiator because they are unnecessary. |
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If he's a farmer he must have water already available... |
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Could you explain how forming a stack of (notoriously
inefficient and somewhat short-lived) cooling elements in
series makes this more reliable? |
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I'd be surprised if he'd stripped the radiators. Burning
hydrogen is generally less thermodynamically efficient
than gas. And then there's the NOx to deal with also
because
although it burns quite hot the energy density isn't there.
Better
to electrolyze it or just take the electricity directly from
the
solar panel, ultimately, at about double the efficiency of
involving hydrogen in the process.
But the refueling potential is
interesting. |
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Toyota made the hydrogen-burning Mirai not too long ago as
a concept. The problem was that to generate the
electricity needed to fill one Mirai with hydrogen every day
would take 2,858 square feet of solar panels in sunny
Phoenix. |
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Hydrogen is also enormously difficult to contain as an atom,
and chemically corrosive to most types of containers. |
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// The problem was that to generate the electricity
needed to fill one Mirai with hydrogen every day would
take 2,858 square feet of solar panels in sunny Phoenix //
That kind of statement/data really annoys me. It's mixing a
bunch of issues and implying that something is bad, but
not really saying anything. |
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1) How much less efficient is electricity->hydrogen->miles
in the Mirai, than electricity->battery->miles in an
equivalently sized electric vehicle. |
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2) How big is the fuel tank? They are bragging about a
distance record of 1003km (623 miles) on a single tank, so
it's got a great big tank. Of course it's going to take a large
solar panel to provide enough energy to drive 623 miles a
day. |
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By a quick and dirty calculation that it probably not apples-
to-apples, it would take 1200 square feet to fully charge a
Tesla Model 3 in a day. But that has a range of 353 miles, so
the hydrogen car is 35% worse efficiency, but has the
benefit of longer range and 5 minute tank refill. I'm not
saying I'm ready to place bets on hydrogen fuel surpassing
battery electric, but the statement that the main problem
was how many square feet of solar panels it takes to fuel it
in a day is complete BS. |
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I'm pretty sure 35% worse than battery electric is still a lot
better than fossil fuel, and if this doesn't have the battery
costs, it could be interesting for situations where
batteries are currently a long shot such as long haul
trucking or airlines. |
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//If he's a farmer he must have water already available...// |
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In his experiments he found that absolutely pure water was required. To filter or purchase pure H2O made it not cost effective so a dehumidifier pulls pure water from the air. |
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//I'd be surprised if he'd stripped the radiators. Burning hydrogen is generally less thermodynamically efficient than gas. And then there's the NOx to deal with also because although it burns quite hot the energy density isn't there. Better to electrolyze it or just take the electricity directly from the solar panel, ultimately, at about double the efficiency of involving hydrogen in the process. But the refueling potential is interesting.// |
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You have to take into account that the straight hydrogen is being released into the combustion chamber as a gas rather than injected as droplets. He didn't report any loss of efficiency in his engines, just that he didn't need radiators anymore because the motors were being cooled from the inside by the expanding gas. |
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I particularly liked the part of the video where he explains that straight hydrogen itself is not flammable and then fills a plastic bottle full, caps it off, passes an electric arc through the bottle to demonstrate, and then opens the bottle into a flame to show that it was indeed filled with hydrogen. |
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I don't know about NOx. Is that a byproduct of burning hydrogen? I thought that the only emission was getting 30% water vapour. |
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//I particularly liked the part of the video where he
explains that
straight hydrogen itself is not flammable and then fills a
plastic
bottle full, caps it off, passes an electric arc through the
bottle to
demonstrate, and then opens the bottle into a flame to
show that it
was indeed filled with hydrogen.// |
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That maybe isn't as remarkable as you seem to think.
That is, there are some compounds for which this isn't true,
and
you can recognise them by the 'explosive' pictogram on the
container. |
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On the other hand, all fuels in everyday use[1] don't fall in
this
category. For example - ethanol ('meths'), petrol/gasoline,
diesel,
coal[2] - none[3] - well, practically none - will burn without
oxygen. |
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[1] Unless your job is a firework engineer, rocket
scientist etc.
[2] Coal will decompose and yield 'coal gas' if heated
enough without oxygen, but it won't burn.
[3] Okay, so dry wood can be carbonized without oxygen,
which is apparently
exothermic with enough heat produced to potentially
sustain the process. Needs a
starting temperature of 280 degrees C. I'm going to call this
an exception. |
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Sorry ... got something in my eye ... |
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Answer: No moving parts, no evaporative materials. |
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Answer: Spread out all around external parts of car radiating
the heat to the air. |
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Answer: No link to the Greek farmer because it was a joke. |
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// can you give a link to the video you're talking about, or any other articles online about this Greek fellow's project?// |
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I tried for quite a while to find it by searching and got no where. Then I remembered that I had starred the email from the person who sent it to me. [link] |
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I'm not sure I understand. It looked to me like he accomplished his goal of maintaining his gasoline equipment after Greece's economy tanked and he couldn't get gas anymore... not saving the world although I think he's headed in the right direction. He shared what he learned. Do you expect Chevron or Exxon to sponsor the alternative to gas and oil without a major infrastructure overhaul? OPEC maybe? |
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Do you have any arguments pertaining to the physics of what he claims, or are we building scarecrows here? |
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Hydrogen is much less energy dense than gasoline.
And whats more problematic is that hydrogen not
obtained from electrolysis is basically obtained
from mined fossil fuels. That which is is a bomb
waiting to happen with the smallest crack. |
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[RayfordSteele]; you can use microbes to produce hydrogen.
See linky. |
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//Like you - youre a dab hand at building things. Go ahead and try it// |
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Someday soon I will have stabilized my life enough to have the luxury of learning what I wish rather than what I need to survive. When this happens I intend to see for myself. |
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Until such time it might help if you could explain instead of browbeat. I already know I don't have your education. |
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//you can use microbes to produce hydrogen.// |
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You can, but it doesn't seem to be a terribly efficient process. I've
seen
people looking at this from the perspective of reusing a waste stream
- where you have the added benefits of 'free' substrate and perhaps
easier disposal.
It's certainly possible that this will be useful, but it's not ready for the
big time yet, and may only ever be a niche thing. |
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//look them up for yourself. Thats a time and cost efficient approach.// |
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No time. Someday though. Until then I get like twenty minutes a day or so not busting my ass while waiting for the first coffee to kick in, so not very cost efficient either as I can barely pay attention while waking up. |
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Yes, I wasted an entire morning finding a video at your request that I watched like seven years ago. |
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Might even have been a couple of mornings. Hard to remember before first coffee. |
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I don't discount backyard inventors, I am one. When stories like Tucker being killed because of his gas vapour engine in like the forties, and the first EV1's being snatched up in a single night until now there's only one left in a museum... and it has no motor in it, become less common place I will put less stock into backyard inventors. When the Reagan administration's first act was to rid the White House of solar panels that was a pretty good indication that things were slipping sideways. Nobody noticed. |
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That my Coanda Tornado has the potential to rid the planet of airborne smokestack particulates from all factories doesn't seem to be making it a reality though does it? Through no fault of its potential. There's no profit in it. |
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Things are the way that they are because of pressure to maintain various status quos. Nothing more. |
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Thanks for wasting my time. |
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//invented a motor that runs entirely off of permanent magnets
and needs no electrical input at all// |
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Did he build one, or just invent it on paper? |
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It sounds to me as if The Big Hairy Entropy Monster would like a
word - but feel free to prove me wrong. |
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