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If I could design one from the ground up I would make it a 6 cylinder with a hot plate to hook up to wood fired stoves for off grid usage and then whatever the efficiency of the engine the rest is used for heating. I would hope for the 6-cylinder arrangement to keep it in even more balance for silent operation. For the cooling side a liquid cooling tower would be used with at least 500 liters of water and connections to replace that water and put the war water into a hot water tank inside a house. I imagine doing this once a day would be done even in Spring and Autumn. Even if this is not done the mass of the water keep at least one room warm for the night. Or you could cycle the water to different water tanks around the house or property. I would make it open to and put a gauge in there and you would have to cycle it manually. But just in case you did put steaming hot water in a system, the other tanks would also be open containers. For the final use it would of course be hooked up to an AC motor for generating AC into a hybrid charge controller for the house. I imagine in 50 years this sort of system being the ultimate in home heating, water and electricity. With a good, solidly built electrical system these would eliminate the need for things such as grid power in many rural areas where it is barely sustainable to get it there as well as big construction projects. I sure would hope to have this system in my home one day alas I do not have the funding to go through with an undertaking as such. Thank you for posting this online Mr. Kirk and for the clear explanations and the open information you have provided. I wish you all the best.

if the hot cylinder has a displacer rather than a close fitting piston then this is a GAMMA cycle not an Alpha. Nothing wrong with that as most sterlings are gamma cycle but let's get it right.

Thank you for taking the time and effort to post this. You've clearly put a lot of time and effort into it, and by sharing this you are answering many questions that capable DIY builders have. I would be very interested in something like this that is optimized to run on wood-gas, and the generator is wound to produce 48V, as a back-up to a wind/solar off-grid electrical system. I cannot make propane at a remote cabin, but I can make wood-gas if I have plenty of trees.

Very Very Nice !!

Excellent, really fascinating and well done. What sort of amps does it push out and how much gas does it use?🎉

I imagine the air leak coming from the front crankshaft seal considering it is not made to hold air, if I to redesign this setup then what I will do is build the generator on the flywheel and Hermetic seal it together, imagine a five gallon pail in front of the engine secured to a plate mounted on the front of the engine at that point a higher pressure could be utilized as high as an air compressor, that's an idea; build it inside an air compressor tank, I'm sure you get the idea of how to make it work there will be no need for the front crankshaft seal to hold air pressure inside the crankcase except to hold the oil from leaking, I used to be in the automotive business for 38 years and one of the problem we faced is a non-functioning crankshaft ventilation PCV in which engine oil will be spitting all over the place, it was a common problem in'89.90 Jeep Cherokees with straight 6 4.0 L engine .

I think there is still much improvement that could be made. 1. There is no insulation and heat transfer between the new and burned air in the burner, much of the heat escapes unhindered through the opening. 2. Free piston design would probably have less friction. 3. What kind of generator is being used ? A stepper motor or a brushless motor / generator would be best. 4. Is there no battery to be charged ? 5. The engine should work much better with pressurized helium. Also why an alpha configuration in the first place ? In this case, because most components are already build and can be picked off the shelf, but for a dedicated stirling type engine a Gamma or Beta or even free piston or even more modern a Thermoacoustic type engine would be much much simpler and cheaper. A thermoscoustic type engine for example does not have any moving parts besides the membrane which replaces the power piston. No small tolerances and machining needed at all. Bot the displacer piston and the working piston are made out of air so to speak, which is the cheapest and least machining needed part that can be. This engine here is very nice, very well build but why is this 70 year old design used ? Why nothing new ? We can build much better machines in the mean time. For instance we can 3D print metal parts and optimize for strength weight and surface area in the burned for instance. Even the 70 year old Philips design used Beta Stirling configuration. This is the part that keeps annoying me, all this time spend for this old design, why not a free piston stirling or thermoacoustic ? I have build one out of dog food cans and I can trickle charge my phone with it. I didn´t use any type of machining, just some cans, steel wool, insulation material, rubber membranes, magnets and a 3D printed spool holder + copper wire and full bridge rectifier. Given proper engineering and materials the engine could be improved tenfold.

Dear David, May I ask if you are selling these generators at the moment? If so, where can I buy one and what would the price be? Regards

2-5 minutes of runtime and no load🤔🤯? I've built aluminum and tin can models that ran multiple days constantly. Nice work but simplifying is the better approach

Did this ever get to market?

You never showed the regenerator as a disassembled part, as part of the cylinder head assembly, what or how is the regenerator made?

Get this to work producing 1Hp I will buy one.

Congratulation on this sensationally beautiful prototype. However, I had the impression that a Sterling engine was meant to run on any "waste heat." Would that be true? Therefore, what minimum heat intensity is required to bring about the "Stirling effect?" Also, I am truly sorry for your friend's early death as your mentor and helper in the construction of this best ever Stirling Engine I saw.

Final product available??

What a beautiful piece of engineering. You were talking about application as an (approx) 750w generator, i just wanted to give you an idea where i think a production version of this would excell greatly if it can be made at a similar price to a conventional 1000w invertor generator. I live on a boat and many others use boats for a hobby, when we moor we currently have only solar or a piston generator to maintain batteries and provide mains power. Running an invertor generator is too loud for long periods when other people are nearby. The boat environment means there is an unlimited supply of cooling water for the cold side, it merely needs a hose to pull water from the river and a suitable pump (maybe crank driven). If this device can be made compact enough to be lifted from a locker and placed on the bank by one person then i believe if it is powerfull enough to drive the multiphase alternator from an invertor generator which is then converted to high-voltage DC and back to 50hz A/C via the standard invertor gen electronics then i believe you have found your market. Quite running is essential in this environment and also due to fuel availability on the river bank a burner which can be powered by diesel or kerrosene would make this extremely desirable to boat owners. The most popular conventional generator used in this consumer group is the honda eu1000i and the 750 variant. These produce 1000w and 750w respectively and are regulated via the invertor technology meaning a stable set speed rpm is not necassary since the conversion between dc and ac takes care of these parameters. The 750w varient for example does not use variable speed control only 2 speed settings for 300w and 750w output selection, it seems a perfect match for the claimed power of your machine. The piston engine used in an invertor generator is a 60cc 4 stroke which i believe is rated at approx 1hp. I personally would love to see a device like yours come into fruition since the exhaust from a burner could even allow it to be fitted inside the boat with a thru hull exhaust similar to a diesel heater. Hope these ideas lead to something great! Mat.

Where can I buy one of these? Are you selling plans?

amazing engine! why isn't this guy a millionaire?

The foil regenerator is one of the most important parts for a stirling engine, and the trick with the ouncturing wheel for uniform spacing is genius, thank you. My question here would only be, how do you make sure that the displacer does not touch the foil ? Or does it slightly touch it on the bumps ?

Bravo........wow........great school...........be funny to run air compressor and run a cryogenic lube .........cheers

I think it would be a good machine for the Ukrainian military. In the trenches, excessive noise can attract the attention of the enemy, so a generator with a Stirling engine has many advantages over a gasoline one. In addition, oil fuel is also a problem, because our refineries have been destroyed by rockets. Also, this generator would be very useful for hundreds of thousands of Ukrainian villagers in the event of a blackout due to missile strikes. Many have returned to heating with firewood. Is it possible to modernize the structure? Turn the heater down and place the electric generator opposite the cold cylinder to balance the whole structure? Then the heater could be inserted directly into the furnace and, along with heating the house, generate electricity. Combined with an old car battery and an inverter, this thing will make the house completely energy independent!

how about a small generator powered by a wood stove?

In my opinion it is not an alpha-cycle Stirling but a gamma-cycle Stirling. You have only one working piston. The other piston is a displacer, to shift the gas from the hot to the cold side and back.

Where's your regenerator?

Do you read my message?

hello

Hello. Can this Stirling engine be bought?

Prestamelo un ratito

any progress?

Not suitable for hobbiests? Seriously? Have you seen the home built plast 3d printed wire EDM that lives on CZcams? Great job, btw!

Come fare per averne 1?

una pregunta si se aumenta la presión interior del gas por ejemplo a 100 bares si aumentaría su producción a kilovatios?? otra pregunta cual de los dos gases para un motor Stirling es mejor usar: si nitrógeno o helio y por que?? te quiero dar muchas gracias con este video me pareció fabulosos me sacase de varias dudas que tenia, estas eran teóricas. te agradezco por compartir esta gran información a las personas que le llaman mucho la atención este tipo de motores Dios te bendiga y sigue compartiendo mas de este tipoi de contenido

Is there a market? Yes. I could pair this with my gasifier and charge my 20kW batteries.

Great video! I'm impressed by the attention to details you've put into that Stirling engine! I really like to see attempt at pressurized chamber - this proportionally increases the work that the engine can produce, and is imho the only way to proper Stirling engine. However I don't like the use of air (or Nitrogen) as it has about 5 times lower thermal conductivity of Helium (and almost 7 times that of Hydrogen). At ~6 bars you're just compensating the low thermal conductivity of Nitrogen, and to do more work a Stirling engine should operate at high pressures with high thermal conductivity gas. In a video of Philips Stirling Cryogenics they're using 100 bars. Of course leaks would be the main challenge with pressurized Hydrogen or Helium, but imho it's the way to go. I'm not engineer and not familiar with the challenge of isolating a piston from leaks of pressurized H or He, but I guess if nothing else a magnetic piston can be used over the wall of the cylinder to ensure zero change for the gas to escape (I guess at 0% leaks even Hydrogen would be safe, as it's exactly the leaks of H that create the main danger). Another thing that you can improve or at least switch to greener alternative is the heat source. As you know Stirling engine has nothing to do with combustion at all, it's just the easiest way to deliver heat. But 600°C you can make a simple mirrors (or perhaps Fresnel lens) structure to capture and concentrate sunlight to the Hot tank. By the way if using sunlight you might want to put the Hot tank under glass cover, to ensure that the high frequency light waves pass thru, but that the infra-red waves of the generated heat can't penetrate back from the inside and escape. Actually as you know temp. difference is critical for the Stirling engine efficiency, so going over 600°C would help greatly, and shouldn't be difficult - just concentrate more sunlight (or btw most gas torches can easily reach 1200~1400°C). Lowering the Cold tank temp is also very important 100°C is rather high. Actually for the same temp.diff. if it's closer to the absolute 0°K the better your engine efficiency will be. At 100°C Cold & 600°C Hot tanks you'll be limited to about 57% max. theoretical efficiency (if you can reach higher 30-ies % in real world efficiency would be already great achievement and probably impossible to improve without major redesign). But if you can take the Cold tank temp to 20°C with the same 500°C difference you'll get 6% higher efficiency (potentially 3-4% real world eff.) ... to the 600°C you're working with you'll get 6% more max.eff. and if you can deliver ~1200°C of a gas torch you can reach up to 80% max.eff. (ie that could translate to about 40 to 53% real world eff.) I'm greatly impressed by your effort to minimize the noise and wear'n'tear! From what I can tell about half the noise was produced by the burning fuel (which replaced by CSP can eliminate it). Perhaps designing the Hot tank to switch between fossil fuel burner and a CSP during the day would be very convenient as a generator usage. Btw for a better solar power receiver I would paint the fins around the Hot tank in something like Vanta black and put a glass container around it (ideally closed to avoid loss of heat by escaping hot air). This way the black surface would absorb the sunlight faster, and the glass cover would trap the produced infra-red waves inside (actually a double layered glass cover would be ideal as the vacuum between the two layers would reduce greatly the heat loss thru conduction). Roughly speaking given that average solar radiation is about 1000W/m², if you can capture 80% of it and turn half of it into usable energy, you'll be doing great! (Twice as good as PV panels!) I know that as a car engine a Stirling won't be a good solution (at least not competitive to the existing ones), because Stirling engine lacks torque, and high efficiency and safety can be a challenge in a restricted space of a car. But a stationary solar energy harvester imo Stirling engine can do amazing, and you'd like you can charge your EV with some of that energy and still drive at very low expense and cleanly (and preferably with cheaper cars ones battery prices come down). If a CSP system is scaled up enough you can use part of the harvested energy to store it in Cryo Cold tanks (perhaps in the form of liquid air with appropriate insulation of course) btw Stirling engines make great cryo heat pump too! And later when the sun is out you can use the stored temp. diff. (to the outside env. temp, or a gas operated Hot tank) to convert it back to electricity with great efficiency (~73% for -196° & 16°C, or even 91% for -196°C and 600°C burner)

Nicely done! Any updates? (Sorry about your friend Arch)

No new videos?

Thank you 🌡️🍀⚡🍀⚡🍀🌻

Any updates?

What has happened to this very promising work? Has it joined the large pile of literally hundreds of stirling engine prototypes that were never completed and never became marketable products? How has this advanced beyond Philip's engines of the 1940s? The last update was four years ago...where are you?

Looks like a Chrysler A/C compressor (base). I'm super intrigued! (D'Oh, I should have listened before I commented!). Amazing work.

The best Stirling I've ever seen! Great job!

where can I get this

Nicely engineered but highly impractical. 900° C? In addition, alpha is the least efficient Stirling engine. This is a beautiful machine, but only a toy.

It would be nice to see what kind of actual work load it might accomplish.

I wonder how much more power you would get from a 125cc motorcycle engine if run on the same amount of Propane gas...?

I am inspired by this engine truly!

Hi! Any update on Stirling Engine SV-2 Mk II?

are you stilll woking on this project?

The propane tank was put in the coolant water. As the propane tank empties, it cools. Cooling the coolant water. Neat!

mi vendi un generatore come questo? 😃

Best stirling engine. 0% chance that big oil & government will allow this thing a spot in the market place.