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HydroICE Project Developing a Solar-Powered Combustion Engine
cylonlover writes "OK, first things first – stop picturing a car with solar panels connected to its engine. What Missouri-based inventors Matt Bellue and Ben Cooper are working on is something a little different than that. They want to take an internal combustion engine, and run it on water and solar-heated oil instead of gasoline. That engine could then be hooked up to a generator, to provide clean electricity. While that may sound a little iffy to some, Bellue and Cooper have already built a small-scale prototype."
Separating oil and water which have been mixed at such a fine level doesn't seem the easiest. While I know it can be done, can it be done in such a manner to maintain any of the heat energy which remains? Or does one just accept that energy as lost?
It is in fact a steam engine, using solar-heated oil to flash water to steam right in the cylinder.
And since TFA can't be arsed to state a single reason why one might choose this over, say, a Stirling heat engine, I'm going to assume there's no good ones.
I doubt that this will ever come close to the high efficiency of a Stirling engine...
While the engine may ideally just vaporize the water with hot oil, the reactions involved would eventually degrade the oil. Additionally, the separations processes are often 50% of the whole system's energy requirements, I just wouldn't see the viability of such a system. Now a heat exchanger for hot oil/water vaporization would wake a lot more sense, but it seems they want to generate a funding buzz with an internal engine spin.
It's not being burned, it's only being used as a heat carrier. Seems to me it would be more efficient to just heat the water directly, and use it in a steam turbine. What am I missing here?
... that Slashdot had been finally invaded by the 'run your ICE-powered device on water' fraudsters who are all over the car forums on the web now. Thankful to find its just a bad description of using steam expansion as part of a power stroke (BMW tested the same theory using steam generated or augmented by the engines cooling system a few years back, although it worked for them they couldnt get the costs of it to be viable)
For the record before anyone does start talking about vehicle water injection, it adds no power per se, all it does is increase implied octane ratings by adding better cooling and detonation control, exactly the same way a well-designed intercooler would but with the added risk that it steam-cleans the oil from the cylinder walls and probably shortens the engine life as a result. Not to mention the effect on the cat and tailpipe from the increased moisture in the exhaust
I have been a user for about 10 years. This ends Feb 2014. The site's been ruined. I'm off. Dice, FU
I just read TFA, and what is described is in no way a combustion engine. Nothing is combusted.
What it actually is, is a concentrating solar thermal piston engine, using steam as the working medium and oil as a heat transfer medium.
It is a direct competitor to concentrating solar stirling engines, and does not seem particularly better than them, except for an unsubstantiated claim of being cheaper.
The last comment at the bottom of the article is a post by one of the project team, linking to a FAQ written in response to the comments.
http://hydroice.wordpress.com/
Wouldn't the power density be much higher than in a Stirling engine?
But I see it's already covered. Cute idea but like programming languages, there's thousands of cute engine designes that aren't practical for widespread use.
"Eve of Destruction", it's not just for old hippies anymore...
Instead of oil use liquid sodium! It would be way more efficient!
"an oil" =/= fissile fuel oil
It's a liquid with an extremely high boiling point, that happens to be chemically categorized as an oil. It's used to store heat. The same thing is done on an industrial scale with molten salts.
However, I see no reason why the oil and water need to come in direct contact.
Why would it? That's not a claim they make, and I see no reason to suppose it's true.
This is just a solar powered steam engine...the oil serves no purpose.
Yes, they have reinvented the steam engine.
In this case, literally: it runs on stream. (As opposed to many more modern heat engines, which usually use other working fluids).
The innovation seems to be that they have separated the heat absorption from the expansion of the working fluid.
If the best they can do is 15%, it will not be competitive with photovoltaic, ever. This needs tracking and mirrors, and that kind of moving parts just can't beat the production efficiencies of silicon solar cells.
http://www.geoffreylandis.com
Most people think of "solar" or "wind" as renewable, but in fact, burning straw pellets could also work very well as a heat source and be carbon neutral (renewable). The nice thing about an engine like this is that any form of heat could drive it. Separating combustion from from the pressures in the engine also will eliminate NOx and other pollutants. So even if the solar part doesn't work out (or at night), this idea still has potential for carbon-neutral energy from just about any heat source that can heat up the oil.
I'd pay money to see the first run.
"Eve of Destruction", it's not just for old hippies anymore...
oil is heated by solar collectors then injected into the cylinder along with a few drops of water. the water is converted to steam by the hot oil. the steam pressure drives the piston down. the oil and steam exit through an exhaust port and are recycled. pretty cool.
my first first-post!
Or replace the water with potatoes and get French fries at the same time.
They say a Stirling engine is more expensive because of tighter tolerances than this device, but I don't see why, plenty of people have built their own. Seems to me it's just a matter of economies of scale. Yes you can get cheap two stroke engines atm, because they are already made in the millions. I'm sure it's cheaper to use an existing engine for your demo than building your own from scratch. However, if this use actually become popular and you start building them in thousands of units, beats me why you'd build this over the twice as efficient Stirling engine.
...I see a few issues, some fixable, some less so.
First, while removing the boiler from the whole "steam plant" equation really does help the safety side of things, you have to be VERY VERY SURE that your separator removes ALL the water from your exhaust. Why? Because if you have even a tiny bit of water in your oil tank, and your heat it to 700F, it's going to boil and expand... and suddenly your low-pressure oil reservoir systems just turned into a really weak boiler full of oil that's hot enough to burst into flames. Instead of venting superheated invisible steam that can strip flesh from bones in seconds, you're going to be spurting oil around at temperatures that cause spontaneous combustion when meeting atmospheric oxygen. Not sure if that's really a step up.
Second, while oil and water don't mix, they do tend to form a really annoying to work with mayonnaise-like suspension of oil globules in water when mixed together really well. This takes a long time - or a lot of energy - to completely split apart.
Third, in addition to the previous problems with separating mayonnaise, heat dissipation will be an issue. Internal combustion engines carry a LOT of their waste heat away with exhaust, but in a closed-loop system like the one they're proposing here you need to remove the 85% of the energy you don't convert into work. Steamboats traditionally do this with a condenser that sits in the water, but if you're not near a large body of water, well... let's just say your condensing apparatus is going to be a huge, complicated, and difficult to work with because even if you don't have a high-pressure steam BOILER you're still going to have a high-pressure steam CONDENSER.
You could, of course, run the oil at a cooler temperature... but that drastically cuts back on your efficiency, because your power depends on having a lot of pressure inside the cylinder, and that pressure comes from the steam, and the pressure of the steam depends on the temperature... well, you get the idea. Basic thermodynamics.
So anyway. It's a cute idea, but unless they've got some really amazing tricks to solve the glaring technical fiddly parts I don't think it's going to get very far. I hope I'm wrong... but I don't think I am.
Never underestimate the stupidity inherent in all human beings.
In case anyone thinks this is interesting enough to throw money at it, I got this link from the FAQ page: http://www.indiegogo.com/hydroice.
I thought it was interesting enough to throw it a few bucks. Could be snake oil, but it could also be really cool.
Note to ACs: I usually delete AC replies without reading them. If you want to talk to me, log in.
FTFA: "While it isn’t clear if they’ve actually had the thing running yet..."
However, I see no reason why the oil and water need to come in direct contact.
Keeping them separated guarantees an efficiency loss in any thermal conduction layer that would be required.
As long as the oil is hydrophobic enough (if I remember hydrophobia is a consequence of subatomic particles being oriented close to the 108 angle of the protons in a water molecule; closer to 108 equals more hydrophobic) i think a simple agitation unit would suffice as a "condenser" of sorts for the oil.
This is not a combustion engine, at all. It's an "insert water with hot oil, use generated steam to drive engine, separate back oil and water to reuse" engine.
The potential efficiency is interesting, and the reduction of generated hydrocarbons compared to a normal motor of the awkwardness of creating and handling lead-acid batteries or other awkward electrical energy storage is also interesting. The difficulty of doing reliable water and oil separation for long periods, at low cost and with low power cost, is an interesting one.
A quick review of the Wankel engine also shows that this technology might be better applied there. The engine destroying accidental misfires known to some Wankel designes would not occur, and the problems handling the spark plug or with lubrication also would not apply.
Interesting if it works.
- How hot is this engine going to get (safety)?
- Insulation? (as he says)
- Capture of waste heat? Something like this?
- How is solar energy transferred to oil? With parabolic trough?
- Energy loss due to vibration of one piston?
- Breakdown of oil?
- Any limit to length of pipe running through collector?
It does not use the oil up.
From a distance...
The Solar Energy Generating Systems power plants in the Mojave Desert have been using parabolic mirrors to generate electricity via solar heat for nearly 30 years now, using oil as the heat transfer fluid.
"The sunlight bounces off the mirrors and is directed to a central tube filled with synthetic oil, which heats to over 400 ÂC (750 ÂF). The reflected light focused at the central tube is 71 to 80 times more intense than the ordinary sunlight. The synthetic oil transfers its heat to water, which boils and drives the Rankine cycle steam turbine, thereby generating electricity. Synthetic oil is used to carry the heat (instead of water) to keep the pressure within manageable parameters." From the Wikipedia article on the SEGS operation.
This format of a heat engine isn't "going" anywhere as it would work only on a stationary position where the sun loading could be high with steerable mirrors. You could use molten oil, water or any material you chose to act as a heat source for a heat expansion engine.
For mobile uses, it all comes down to kilocalories stored per kilogram. This solution "won't go anywhere" mobile.
I, for one, salute our margarine powered motors. It oozes, it poofs and it provides for my sanwiches from the behind.
Interesting that the OP got instantly modded down. Suppose the article was about a new computer language and the article described it as a compiler when it really was an interpreter. Bullshit would be called immediately. Same level of error, different tech.
"Eve of Destruction", it's not just for old hippies anymore...
At this stage in development, efficiency isn't a big deal , unless it can be proven early on that it will always be too horrible compared to alternatives...and that only counts if there are alternatives.
What is interesting/important is it's potential as (pointed out lots of times in the comments) a steam engine that avoids big boilers and has the same kick as an ICE since it uses the same mechanical layout. Any other heat-driven engines that can do the same? same kick, same overhead?
reading comments seems to say no so far: Stirling engines don't have the variable torque output for use in cars. Steam boilers are too heavy and involve piping steam around the system (dangerous and complex). Even converting the sunlight directly to electricity runs into storage problems (batteries aren't big enough yet) . I've seen come comments that heated oil may actually be a good way to store solar energy...not sure if it beats batteries, but worth a look.
This is another tool in the toolbox if it works. Is there anything that says this won't?
AB HOC POSSUM VIDERE DOMUM TUUM
I should think the water won't last long in the oil as its being heated to 700 degrees, the watter should boill off and be recoverable with a condensor. This is assuming that you would want a closed circuit for the water.
If the plant isn't efficient as per "energy out" / "energy in" it could still be efficient as per "total energy out lifetime" / "total cost in dollars lifetime".
"better ways of doing things eventually just replace the inferior things" - Linus Torvalds 09-08-07
The WTF for me is how one could produce an aerodynamically stable parabolic collection mirror that would track the sun while perched on a moving and vibrating vehicle. It would be like grampa with his shaking hands trying to get smoke from a leaf with a magnifying glass.
The point of mixing the fluids is that you cannot otherwise impart enough heat to flash boil the water.
That begs the question, can you not otherwise impart enough heat to flash boil the water? Why not a big metallic thermal load, made out of recycled popcans?
That's not begging the question.
That begs the question, how is the original statement not an example of the petitio principii fallacy?
Water injection dates back to the 1920s. It was used because the technology of the day could not use high compression ratios without detonation. Modern technology overcomes detonation by attention to fuel, gas flow, thermal design and ignition timing. Water injection is obsolete.
From scarped cliff or quarried stone she cries "A thousand types are gone, I care for nothing, no not one."
Unfortunately biomass takes up land and is weather dependent. One bad year and it's energy shortages all around.
And what does "Separating combustion from from the pressures in the engine also will eliminate NOx and other pollutants." even mean? NOx creation is temperature dependent. Other pollutants would be fuel dependent.
According to TFA 15% is the same efficiency as photovoltaic but the cost of the system is supposed to be 1/3 of equiv photovoltaic.
Yes, they said that, but they're wrong. No possible way it can get down to 1/3 the cost of photovoltaic panels. I frankly doubt if they can make it as low as twice times the cost of photovoltaic.
On a large enough scale, I think a Brayton engine might make it cheaper than photovoltaic, but part of that is because of the high efficiencies, and the other part the economy of scale of large turbines. I doubt a piston engine can be that cheap, not operating at these temperatures.
Maybe they're thinking about the photovoltaic cost of twenty years ago. PV has gone WAY down in the last few decades.
http://www.geoffreylandis.com
You really have to take into account potential reduction in costs for any technology meant to compete with photovoltaics (not saying this doesn't have that potential).
Why not just heat the damned water to begin with?..
Don't get me wrong; it's a good idea, but I don't see its application beyond power plants.
>What, their fuel injectors? Old fashioned mechanical carburators?
Neither of these nor the rest of that post has anything to do with a Stirling cycle engine.
The parent should be at -1 idiot.
It's mainly high compression ignition that results in NOx. That's why separating the combustion from the piston would really help, if we could do the energy conversion efficiently.
I should think the water won't last long in the oil as its being heated to 700 degrees, the watter should boill off and be recoverable with a condensor.
Only if the water is still steam when it exits the expansion chamber -- which should be easy enough to achieve by balancing the amount of oil and water injected, taking the temperatures of both into consideration.
Note to ACs: I usually delete AC replies without reading them. If you want to talk to me, log in.
These things are always either bad reporting (a reporter not understanding what he's been told/shown or being too gullible) or else a scheme to lure gullible investors by using the press to give a fake "invention" legitimacy
The simple fact is that the sun delivers a certain quantity of energy per square meter to the surface of the earth on the sunniest, most cloud-free day... and not one bit more. If that's enough energy to power something like a car, then it is enough to fry a person who steps outside... and it's not; therefore, you would need some sort of large collector to grab energy from a wider area and concentrate it, and that means more mass, a larger vehicle, and aerodynamic issues. The scheme is not and never will be workable; it's not a problem of materials, or techniques, or lack of innovation... the problem is entirely about low power per unit of surface area.
Maybe they'll use a centrifuge. Maybe electrostatic separation.
Maybe they'll heat the oil with a peltier and use the cool side as "a serious refrigeration unit".
All of those take energy that would sap the efficiency of the system. I'd probably go with a large condensation box that has baffles in it like a septic tank to keep disturbances down. As the liquids cool and travel through/around the baffles, they're slowed and turbulence is minimized.
You might not need a 100% efficient separation system to make it work.
Still, I don't see it being more efficient at this point than traditional steam engines and turbines.
I don't read AC A human right
He wants you to know he has created an engine that does exactly this. heated solution on the hot end of the engine, and it will drive the engine via heat differences, a cold solution on the cold end will only help its efficiency.
Downside is, the amount of energy needed to make this work exceeds the output, however, is great for waste heat applications from an existing system, to increase efficiency of say, an existing power generation system and its waste heat.
The cost for X amount of steel, y amount of machining, z for mirrors, etc...
The costs for PV panels has dropped substantially. At this point I think that only large scale thermal solar will beat it's economy.
I don't read AC A human right
I wonder how much energy can be stored in heated oil compared to batteries. Quick back of the envelop calc shows, 20 gallons of oil, that is about 60 Kg. Specific heat of water is 1 cal/gm/degree, is 60,000 cal/deg, 470 deg over ambient, gives, 60,000x470=2.8e07 cal, or 1.2e08 Joules, or 2.85 Kg of gasoline at 42 MJ/Kg. That is about 0.95 gal of gasoline. 60 Kg battery pack can probably store more energy than 1 gal of gas. And that energy converts to mechanical power at a much greater efficiency than any heat engine. It does not look like an application for cars. May be cheaper fixed installations competing with solar panels may be. May be if the build a tiny steam turbine, it would be more efficient.
Small gas turbines are quite familiar to engineers, all the turbo-charged ICEs use a gas turbine in the exhaust manifold to pack more air into the inlet manifold. So small gas turbines are well understood, but still they are not usually found in the power ranges needed to drive cars and trucks. Heck, even railway locomotives go for 16 cylinder diesels than gas turbines. I wonder why.
sed -e 's/Chuck Norris/Rajnikant/g' joke > fact
This is nothing more then a very complicated external combustion engine. Why not just use a Sterling engine, oh wait, it's already being done and without the need for much of the complexity.
A fax machine that can send and receive e-mail? That would be marketable for legal offices...
I know tobacco is bad for you, so I smoke weed with crack.