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.
-- pashute, Nov 14 2021

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]

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.
-- 2 fries shy of a happy meal, Nov 15 2021


If he's a farmer he must have water already available...
-- Voice, Nov 15 2021


overdone [-]
-- Voice, Nov 15 2021


Could you explain how forming a stack of (notoriously inefficient and somewhat short-lived) cooling elements in series makes this more reliable?
-- Loris, Nov 15 2021


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.

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.

Hydrogen is also enormously difficult to contain as an atom, and chemically corrosive to most types of containers.
-- RayfordSteele, Nov 15 2021


// 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.

1) How much less efficient is electricity->hydrogen->miles in the Mirai, than electricity->battery->miles in an equivalently sized electric vehicle.

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.

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.

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.
-- scad mientist, Nov 15 2021


//If he's a farmer he must have water already available...//

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.

//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.//

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.

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.

I don't know about NOx. Is that a byproduct of burning hydrogen? I thought that the only emission was getting 30% water vapour.
-- 2 fries shy of a happy meal, Nov 15 2021


//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.//

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.

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.

[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.
-- Loris, Nov 15 2021


//firework engineer//

Sorry ... got something in my eye ...
-- pertinax, Nov 15 2021


Answer: No moving parts, no evaporative materials.

Answer: Spread out all around external parts of car radiating the heat to the air.

Answer: No link to the Greek farmer because it was a joke.
-- pashute, Nov 16 2021


// can you give a link to the video you're talking about, or any other articles online about this Greek fellow's project?//

Yes! Found it.

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]
-- 2 fries shy of a happy meal, Nov 16 2021


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?

Do you have any arguments pertaining to the physics of what he claims, or are we building scarecrows here?
-- 2 fries shy of a happy meal, Nov 17 2021


Hydrogen is much less energy dense than gasoline. And what’s 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.
-- RayfordSteele, Nov 17 2021


[RayfordSteele]; you can use microbes to produce hydrogen. See linky.
-- neutrinos_shadow, Nov 17 2021


//Like you - you’re a dab hand at building things. Go ahead and try it//

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.

Until such time it might help if you could explain instead of browbeat.
I already know I don't have your education.

So does everybody else.
-- 2 fries shy of a happy meal, Nov 17 2021


//you can use microbes to produce hydrogen.//

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.
-- Loris, Nov 17 2021


//look them up for yourself. That’s a time and cost efficient approach.//

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.
-- 2 fries shy of a happy meal, Nov 17 2021


Yes, I wasted an entire morning finding a video at your request that I watched like seven years ago.

That'll teach me.
-- 2 fries shy of a happy meal, Nov 17 2021


Might even have been a couple of mornings. Hard to remember before first coffee.

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.

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.

Things are the way that they are because of pressure to maintain various status quos. Nothing more.

Thanks for wasting my time.

As you were.
-- 2 fries shy of a happy meal, Nov 18 2021


//invented a motor that runs entirely off of permanent magnets and needs no electrical input at all//

Did he build one, or just invent it on paper?

It sounds to me as if The Big Hairy Entropy Monster would like a word - but feel free to prove me wrong.
-- pertinax, Nov 18 2021



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