Stirling Engines Now “Extremely Important” to Rossi

Today on the Journal of Nuclear Physics, Andrea Rossi signaled a new interest in connection with his E-Cat: Stirling engines. Stirling engines are heat engines that use the expansion and compression of a gas to provide mechanical energy. Below is a video of Bill Nye demonstrating a simple Stirling engine.

Here are a few comments from the JONP:

Andrea Rossi
October 14, 2017 at 9:51 AM
If any Stirling engine manufacturer has a 50 kW engine ready to be bought, this is the very right moment to contact me.
Warm Regards,

Colin Watters
October 14, 2017 at 2:17 PM
I think Kockums in Sweden may make a 100HP Sterling engine.

Andrea Rossi
October 14, 2017 at 2:50 PM
Colin Watters:
Thank you very much for the information. This issue now is hot.
Warm Regards,

Frank Acland
October 14, 2017 at 4:54 PM
Dear Andrea,

I know you have shown some interest in Stirling engines over the years, but I am wondering what makes the Stirling Engine a “hot” topic for you right now?

Andrea Rossi
October 14, 2017 at 7:38 PM
Frank Acland:
I deem this field extremely important.
Warm Regards,

There have been a number of readers posting suggestions for suppliers of Stirling engines and he seems to be in the mood to get his hands on at least one.

If the E-Cat can provide a constant source of very inexpensive heat, then it might make sense to combine it with a Stirling engine as an efficient means of making use of the E-Cat’s energy — perhaps for generating electricity or operating pumps or drivetrains. Perhaps Rossi sees it as a more attractive method of electricity production than using steam turbines. It will be interesting to see where this might lead.

  • Brokeeper

    Frank, this is a blast-from-the-past of three years ago revisiting discussions about merging Sterling engines with the E-Cat as a possible power source. Specifically we had spoken about a possible partnership with DEKA and its Beacon 10 sterling electric conversion system.
    I find it odd that Andrea Rossi, once a residence of Manchester NH, had not approached Dean Kamen about the Beacon’s great potential for industrial use. Perhaps there is still potential for hand shaking.

    • Frank Acland

      Thanks BK — I remember this, but 3 years later nothing much has come of it. I wonder why not.

      • Dean Kamen also based a water purification plant on a stirling cycle engine and the goal was for it to be $2k and last 20 years IIRC. Nothing came of that, either. I think Dean expected more cooperation from the guvmint as well as NGOs (Non Guvmint Organizations) to help solve the clean water crisis. Those groups are all talk and no action.

  • Rene

    Now think about heat dynamics and the influence of one quark affecting the reaction rate of neighbor ones. Can we say complicated?
    Now think about heat dynamics and the influence of one quark affecting the reaction rate of neighbor ones. Can we say complicated?

    • US_Citizen71

      If he is planning on putting more than one QX together for any application what you have stated would be an issue. Since he is apparently planning to build large clusters research into how multiple QXs interact with each other likely has already been long done. The big issue will be getting efficient heat transfer from the cluster to the hot end of the stirling engine.

    • nietsnie

      The most efficient commercial Stirling engine I can find claims 30% efficiency. So it would seem that, due to the inherent energy loss, a 50kw Stirling engine output would require ~167kw of raw Quark output, resulting in the need for 8334 Quarks. And that presumes zero loss in the energy transfer between the quarks and the Sterling (which is not possible) resulting in the need for even more Quarks.

      This just makes your point more obvious. Rossi needs to begin advertising to fill a permanent position for a Senior Quark Wrangler. How much space do 10,000 Quarks require for efficient operation?

    • TVulgaris

      50 KW is the MAX. output, that’s the way ratings are ALWAYS stated, and usually further qualified as continuous, intermittent, or peak, or yet some other completely squishy marketing adjective (not so likely with an industrial unit, but still, I’ve seen dumber things). The output is going to be a range, not a fixed value.
      What if he’s sizing the thing to the absolute maximum heat output of a small number of QXs based on the MOST optimistic CoP figures? I would…

  • GiveADogABone

    The best that I can find on the Web at short notice and it is designed with a web connection.

    Many Stirling engines are designed for firing internally with fossil fuels. This one makes it obvious that placing the hot end of the engine in separate ductwork containing hot gas/air is available.

    This engine is rated at 5kW 240V single phase (or 400V 3-phase) continuous, via an inverter, but the Inresol website discusses larger, containerized versions with multiple engines fed by a single heat source.
    The Stirling engine power generator

  • BillH

    Contrary to what was said in the video Sterling engines are not very efficient, perhaps 10 to 30%, so you still have the problem of all that waste heat, and you haven’t turned it into electricity which would introduce more losses. Seems like two steps backwards to me.

    • Frank Acland

      Maybe AR is thinking of a Stirling engine in terms of cogeneration.

    • Ewin Barnett

      Up until LENR, every increment of energy input was costly, so there is naturally a lot of attention paid to putting every joule to work. There are also gaseous emissions to justify.
      Randy Mills of Brilliant Light Power points out that when the energy is almost free, then the issue of efficiency changes to a focus on the cost of the final product at the customer site. In the case of BLP, Mills just dumps excess energy as hot air.

    • Thomas Kaminski

      Please give a reference to your efficiency numbers.

      • BillH


        Wikipedia quotes various figure, with 50% being a theoretical max

        But these would be huge expensive devices, if any have actually been built.

        • Thomas Kaminski

          The 50% efficiency is attributed to a practical engine in the reference that Wikipedia uses for that figure, not a theoretical max. Actually, anything over 30% is pretty good. Only the most efficient power plants approach 50%. Many older plants are operated at around 30%.

          • GiveADogABone

            There is clearly scope for confusion between the Carnot efficiency of an engine and the overall thermal efficiency of a heat source and engine. I reckon Wikipedia means the engine alone. With a heat source (using combustion) that is only 50% efficient, the overall efficiency would be 25%.

          • Steve Savage

            Thomas… Should we not consider the efficiency of such a device as not being all that important, considering the energy that drives it is essentially “free” ? To be sure, if there were 2 or 3 major alternatives, the most efficient would win *( not considering other engineering consideration such as power to weight, durability, initial cost) … perhaps even 10% might be good enough?

          • Thomas Kaminski

            Perhaps you are right. However, dealing with the increased waste heat to produce a fixed amount of mechanical energy out might itself become a problem. Clearly, the higher the efficiency, the less waste heat you have to deal with for a given level of mechanical power out.

            In cases where the heat is needed and can be gotten from waste heat, the efficiency is less important. One example of this is remote data stations in Antarctica. I have heard that at least one uses propane and ThermoElectricConversion devices to both power and keep the instruments warm, even though the TE device efficiency is less than 10%. The mechanical simplicity and reliability of TECs wins where remote repair is difficult. NASA’s voyager spacecraft (my dandruff flakes are on one of the instruments onboard) use RTGs and are still operating after 40+ years!

        • Omega Z

          Decades ago, A sterling engine was designed that they hoped would reach 40% efficiency. However, it was never actually built because of size weight and cost. Thus, the efficiency was never proven.

    • Albert D. Kallal

      Sterling’s are reasonable efficient. What they don’t have is great power to weight. (A different
      issue). So you don’t see weed eaters or lawnmowers based on sterling engines.
      It not an issue of “energy conversion” rate but that of power to weight ratio tends to be far lower.
      Sterlings do a fine job in energy conversion rates.

      So there are a number of CHP (combined heat and power) systems based on sterling engines.
      The “critical” feature of the sterling is LOW maintains. You need something like your fridge. You plug it in for 10 years and don’t worry about it. This type of “appliance” based on
      LENR is no doubt the HOLY GRAIL of energy for consumers. This event
      will be the difference between a home computer kit, and a pre-made computer
      that revolutionized the world in ways we could never imagine. We typing and
      talking on this forum due to this astounding computer revolution.

      So you purchase a device about the size of a washing machine. Plug it in down in your furnace
      room. The device converts the heat into electricity, and any excess heat is used for hot water, and of course to heat your house.

      So any excess heat is for hot water and heating your house. And of course you can toss in an absorption chiller for air conditioning.

      Gee, an appliance that provides all your heat, all your hot water, all your electricity? Gee, no
      one would want that, would they??? 😉 Talk about a Mr. Fusion in your basement!!!

      So a “box” that runs for 10 years without any maintains that provides all your energy needs?
      Gee, I wonder if anyone would want such a box based on LENR? Just a spit
      balling here!!!

      The REAL computer revolution occurred when we jumped computer “kits” to pre-packaged computers that you just plug in, turn on, and you off to the races. This is the difference
      like the Wright Brothers flying a plane vs you going on-line and booking your holiday
      and then jumping on a JET that can take you anywhere in the world. The JET age
      transformed the world more then we could imagine.

      Of course this is a match made in heaven. This kind of LENR setup will the “big thing” and “black
      swan” device that will transform the world. Such devices will represent the true dawn of the LENR age that will change the world forever.

      Albert D. Kallal
      Edmonton, Alberta Canada

      • TVulgaris

        The original Apple II (and several other OOB units) didn’t rapidly change the computer field from the original hobbyist market- that took the IBM PC and ISA; it probably would have taken another decade for Apple and the other early manufacturers to make the kind of dent in the mass market that the 5150 did in less than 3, and the entire industry would probably be unrecognizable (probably the world, too).
        I strongly suspect LENR deployment won’t take less than the generation-long process of PC acceptance that led to its pervasion of the culture- UNLESS some process that enables the world’s poor (that’s nearly all of us on the planet) reasonable access to it. I don’t see that ever happening in any conventional capitalist country, and probably questionable in the unconventional poor nations like Bhutan.
        Had I the resources, I’d have bought a PowerWall the day they were released, simply for load-smoothing, even though I can’t (yet) put solar on my business- and it still would have been a wise long-term investment, that would become short-term with the installation of any generation capacity- but I don’t have the resources.
        From all indications for the past five years (at least) Dr. Rossi has paid no attention whatsoever to the pervasive deployment of the technology (which I recognize is certainly not his responsibility) but there is certainly no OTHER involved party who’s done so in any concrete terms.

  • Gerard McEk

    For a demonstration it would be very nice to show a total grid independent system: An E-cat QX generating heat, a sterling motor combined with a generator and an UPS. The generator makes electricity for both the UPS and an external load. The UPS provides uninterrupted electricity to the control an required power to the QX. It would be a great demo!
    I do think though, that the time is too short for the November demonstration, if Andrea is thinking about this.
    Besides that, the efficiency would be much higher if the E-cat QX would be fully integrated with the hot side of the sterling motor, providing heat far over 1000 degrees.

    • US_Citizen71

      Perhaps a second bigger more publicized demonstration might be in the cards. Maybe he plans to demonstrate a good calorimetry setup that shows net energy production with the first demonstration to please the scientists and academia. Then maybe the plan is to power the calorimetry setup and other items doing useful work (a large tea kettle, water pumps, lights, etc…) with a self powering and sustaining QX heated sterling generator during a press conference style demonstration. That is how I would do it.

      • Bruce__H

        You are right on the button that a simple, transparent, caliorimetry setup used in a solid scientific setup would please the scientists is the way to go. But I doubt that is what will happen. I think that Mr Rossi is bringing up the Stirling engine now because he intends to substitute it for straightforward caliorimetry during the demonstration.

      • Buck

        October 15, 2017 at 1:58 PM

        Good Day Andrea:

        I hope this finds you well and far a long the path towards the upcoming demonstration.

        With your revived interest in Stirling engines, an idea has floated . . . that you will present two distinct demonstrations of Rossi effect. The first is the basic irrefutable water calorimetric setup proving the
        essentials of the theory that LENR does have the capacity of a COP far greater than 1. The second would be with the ~50KW Stirling engine; a demonstration acting as a bridge from the theoretical proof of the 1st setup to an extremely practical demonstration of what the Rossi effect can do in an industrial setting.

        It is my hope that your plans reflect this idea . . . I believe you can see how it will effect the conclusions of those observing the demonstration. Strangely, I see it like the Lugano report’s ability to disarm the doubters. The two parts (energy input/output measurement and elemental/isotopic analysis) overwhelmed the possible scenarios of fakery.

        My best to you, your team, and your tennis instructor.


        Andrea Rossi
        October 15, 2017 at 2:17 PM


        The demo of November will not be made by means of a Stirling Engine.

        The R&D for an application to engines ( not necessarily Stirling) has been due to other factors.

        Warm Regards,



        My tennis instructor ( my wife ) says I am hopeless.

    • CWatters

      Rossi has since said that the demo will not feature a Stirling engine.

  • GiveADogABone

    @ BillH, Ewin Barnett, Brokeeper & Frank
    May I suggest a look at the graph on page 15 of [1:] .
    It plots Brayton cycle efficiences against source temperatures.
    At 600C the thermal efficiency varies from 30% to 45%.
    At 1000C the thermal efficiency varies from 50% to 60%.
    What is wrong with that?

    What Rossi has spotted is that there are TWO major heat losses in conventional Stirling engines, heated by fossil fuel :-
    1: The Carnot Efficiency of the Stirling engine, more appropriately the Brayton cycle efficiency, and
    2: the very poor efficiency of a conventional heat source that is dependent on combustion.

    The heat loss in 2: is caused by the need to reject heat from the heat source at a temperature in EXCESS of the hot temperature of the Stirling engine. That means that you waste something like half the heat of combustion, before any heat gets to the engine. With a CLOSED cycle in the QX and Stirling engine hot end circuit, there is NO heat rejection in the heat source, so the overall efficiency of the Stirling engine becomes something like double what we were used to in days past.

    He or CO2 Closed Brayton Cycles (CBC)
    page 15: Cycle Efficiencies vs Source Temperature

    • Thomas Kaminski

      A third point it the difficulty of producing heat exchangers with combustion products on one side and fine geometries that can withstand the corrosive effects of high-temperature combustion byproducts. The QX, being quite small (surface to volume ratio is high) and that can be totally enclosed in a pressure vessel (I think), would eliminate that problem as well. Typical Stirling heat exchangers pay the heat exchange penalty twice — once on the combustion side and again on the internal gas side.

  • Ted

    Ripasso Energy has newly developed Stirling Engine aswell, based on Kockums I think

  • Zephir

    /* Stirling Engines Now “Extremely Important” to Rossi */

    This is exactly, what I said here. The future of EMDrive isn’t in electricity conversion, because the cars do need the mechanical energy at the very end. Rossi is strategist way ahead than most people here.

  • He should just buy Cypress Power CYPW on the pink sheets (if they’re still even on the pink sheets). He can pick up interesting and patented Stirling Cycle technology for pennies on the dollar.

    • artefact

      you mean Cyclone Power not Cypress Power? 🙂

      • Oops. Thanks for the correction.

  • artefact

    Advantages and disadvantages of Stirling engines

    ” its cost is probably the most important problem, it is not yet competitive with other means well established. A generalization of its employment should solve this problem inherent in any novelty”

  • Frechette

    The modern Swedish Gotland Class Submarines use Sterling engines which make them the quietest boats in service.

    This characteristic of Sterling engines would be welcome for a domestic in the basement type application.

  • magicsnd1

    Stirling Energy Systems built a demo concentrator system in Arizona, about 100 steerable dishes at 10 kW each. They had reliability issues with the Stirling engines, and the mirrors needed constant cleaning. I tried to visit it on a road trip, but the gate was too far from the array to see much. It’s gone now.

  • CWatters

    Rossi reports difficulty getting a reply from the companies that make Stirling engines.

    • Buck

      In the following exchange, Rossi implies that he is having some success. We here are highlighting the dead-ends leaving a collective bad taste.


      October 16, 2017 at 4:59 PM

      Hello Andrea:

      regarding your interest in Stirling Engines, it sounds like you have hit several dead-ends. It is my hope is that you have had luck reaching out to Dean Kamen of Deka Research regarding their Beacon 10. Here are
      some good links to the Deka.

      my best,



      Andrea Rossi
      October 16, 2017 at 7:08 PM


      Thank you for the information. We are contacting all the companies our readers are signaling to us.

      Warm Regards,


      • Brokeeper

        Hi Buck, I did a little research whether Rossi had contacted Dean Kamen or DEKA about the sterling engine. It appears Rossi may have four years ago when he received a proposal of concept that may now lead to the Beacon 10 but not a working product then:

        Chris Johnson

        June 28th, 2013 at 11:55 AM

        Have you looked at the Stirling Engine from Dean Kamen / Deka Research in
        Manchestre, NH? Kamen is the inventor of the Segway and the “Luke Arm” ( ) among other things. He is always
        working to create technology that can make a huge impact on the world. His
        Stirling system produces electricity and fresh water, using any burnable fuel as
        a heat source. See
        for an instance where it has been used for fresh water and electricity in two
        remote villages.

        He has been perfecting Stirling technology for over 10 years and thinks that he
        can get down to a cost of $1 per electric watt in mass production. The
        prototypes are much more expensive, but perhaps you could have some sort of
        cooperative development agreement.

        Best Regards

        Andrea Rossi

        June 28th, 2013 at 5:02 PM

        Chris Johnson:
        We contacted all, but so far all we have are proposals of concepts to be
        developed, patents, ideas etc. We need a solid product that we can buy and test.
        We did not yet have a real offer, so far, for an existing and working real
        product. If somebody has it, please send an offer ( not a phylosophical concept
        otr a petent pending) to
        [email protected]
        with price, delivery term. We are not interested to theories, concepts to be
        developed and patents without a real product.
        Warm Regards,

        Also a year later from Frank:

        Frank Acland

        December 22nd, 2014 at 10:45 AM

        Dear Andrea,

        Are you familiar with a product being developed by the US Utility NRG called the
        ‘Beacon 10’? It is the invention of Dean Kamen (of Segway fame) who is working
        in partnership with NRG on the product.

        Basically it is a Stirling engine-based generator that is designed to produce
        electricity from a home’s natural gas source.

        The first model will apparently be a 10kw model which will be suitable for
        commercial buildings. A smaller 2.5 kw for home use is in the plans.

        I see no reason why, technically, this could not work with E-Cat heat.

        You can read more about it here:

        I thought you might find this interesting, if you were not already aware of it.

        Kind regards,
        Frank Acland

        Andrea Rossi
        December 22nd, 2014 at 11:31 AM

        Frank Acland:
        Thank you for the information: no, I am not familiar with it, even if I
        contacted them a year ago or so and they were not ready with a product for our
        Warm Regards,

        • Buck


          thank you for the reminders. I think Deka/Dean Kamen would be a good fit now that Deka has a fully designed product in the Beacon 10. Further, Kamen has a strong engineering reputation along with a history of working towards a goal of doing good.

          Time will tell how it all turns out with Rossi.

          • Brokeeper

            Agree, both very much have the same humanitarian philosophies and inventive systematic approaches. They could feed off of each other quite well if they can get past their strong wills. 😉

  • Ice Nine

    This gentleman looks like he would be willing to supply a unit, runs on waste heat saturated steam, very affordable.

  • Paul Smith

    Andrea Rossi
    October 16, 2017 at 7:06 PM
    Koen Vandewalle:
    Within one year I want to see an engine operated by the E-Cat QX.
    Warm Regards,

  • Gerold


    Maybe this information on sterlings engines used in bio mass powerplants might help. ?


  • Zephir

    Ceramic pump moves molten metal at a record 1,400 degrees Celsius A ceramic-based mechanical pump able to operate at record temperatures of more than 1,400 degrees Celsius (1,673 Kelvin) can transfer high temperature liquids such as molten tin, enabling a new generation of energy conversion and storage systems.

    • Steve Swatman

      Doesnt Mr Rossi have a patent on such a pump or pumping setup for molten lead.

  • Albert D. Kallal

    There was quite a few Stirling engines that came into being with based around the idea of a “dish” to focus
    the sun on the engine.

    A number of companies thus raised money, and that in turn allowed some rather “nice” Stirling engines to
    be built with investors’ money. So money was going into “Stirling” engines.

    However, that was about 8-9 years ago. Now with the spectacular drop in solar (PV) systems then
    the Stirling idea took a BIG hit.

    PV’s are real science fiction. I mean, if there anything I ever seen that boggles the mind? It has to
    be PV’s – they are crazy flat panels, no moving parts, and with some sun then out
    comes electricity? Wow!

    Ok, back to Stirling’s.

    I can see why Rossi having trouble find a decent Stirling engine. With the above “business” collapse
    of dish + Stirling falling by the wayside, then all the companies, web sites,
    and links are now out of date.

    One of my favorites was this one:

    The above has a REALLY brilliant method of converting up/down motion into rotary (I am sure
    you all familiar with James Watt REFUSING to pay for the rights to use a simple crank shaft that someone else owned the rights to – yes, a patient existed for the crank shaft). So Mr. Watt hired a engineer to get around the patients on a simple crankshaft to convert up-down motion to circular.
    Anyway, the above watch is worth it just for the conversion of up/down to circular.

    Sad part? The companies web site is gone – they don’t seem to be active. (and as many noted –
    lot of such makers have gone by the wayside).

    Next up would be of course DEKA. This is Dean Kamen’s company. They built the iBot (the standing
    wheelchair), and the Segway – that 2 wheel transport device. And personal/portable insulin pumps, and of course the Luke arm (if you not seen that bit of science fiction, then you want to).

    Their site is still up, and their Beacon 10 design is near perfect. Again, no info on their
    Stirling, but at least the company still around!

    Here is a video of a prototype in action:

    DEKA would also love LENR, so DEKA would be a great company.

    Albert D. Kallal
    Edmonton, Alberta Canada

    • Brokeeper

      It’s hard to understand “we still have not been able to get the offer for a real product.” from DEKA. Unless they have not updated thier Web site and taken the Beacon 10 off the table.

      • Frank Acland

        I don’t think they are in production yet, based on this article:

        “DEKA has built refrigerator-sized Stirling engines, powered by natural gas, that it says can generate 10 kilowatts of electricity and 40 kilowatts of heat. (I didn’t even know you could measure heat in kilowatts; energy units sure are confusing.)
        A couple of these units have been helping power DEKA’s millyard building at 100 Commercial St. since late 2013 as part of a test, and the company has several more operating in other buildings hither and yon. It says they are living up to their promise, and now DEKA would like to put one in a state building in Concord to give the project a much higher profile.”

        • Brokeeper

          I left a phone message to the project manager inquiring as to any possible chance to partner with Rossi stating the potential is huge. I’m not holding my breath though for a response, but it could be interesting if he does.

        • Rene

          Frank, it is common to measure heat in KW. BTUs tend to be used here for heat but the KW equivalents are nowadays shown. 40KW eat is about 136K BTU/hr

          But why would anyone want to partner and expend funds with someone who has yet demonstrated they can reliably produce 10-40KW of heat let alone 20W. Time to wait for a serious verifiable demo.

  • Wholewitt

    Albert, your spell checker changed patent to patient in two places (below the video). Also, a warning, do not go to the whispergen-europe web site, it will take control of your computer. If that happens you must force your computer off using a reset button then reboot.

    • Albert D. Kallal

      Thanks – fixed the patient to patent issue (and yes, it is my spell checker – I have it on as I type – always in a hurry and always limited time).

      As for the wispergen site? it was only “dead” for me – but again thanks for the heads up. I did hit their site – and some “ad” crazy vendor or aggregate system pops up – but no freeze or issues on my end.
      However, I certainly did not provide a link, and a nice heads up for readers here to avoid the site name as it stands.
      So their site don’t work – but don’t try it either!!

  • Charles Davis

    I suspect that Andrea wants to use the stirling engine to run a generator similar to this one

  • GiveADogABone

    Until recently, there was a Stirling engine in a UK government renewable energy scheme under the moniker micro-CHP. It was called a Baxi Ecogen. I decided to try and trace the source of the engine. This history was useful :
    The Microgen unit, developed by BG Group from a US (Sunpower) design, is a LFPSE which is intended for wall-mounting; … Following disposal by BG Group in 2007, development of the Microgen unit was taken over by MEC, a consortium of gas boiler companies (Viessmann, Baxi, Vaillant, Remeha) and Sunpower.
    Each of the boiler companies has developed their own variant of micro CHP unit incorporating the MEC engine, now being manufactured in China.
    The UK variant is manufactured by Baxi, part of the BDR Thermea Group which also includes Remeha, De Dietrich and Brötje.

    This web address has already been sent to Rossi by Colin Watters.
    The base specifications
    Maximum (modulating) electrical output: 1050 watt
    Characteristics of electrical output: nominal 230 volt, min 186 – max 264 v
    Frequency: 50 HZ or 60 HZ
    Weight without burner: 49 kg
    Dimensions without burner: 450 mm in height and 300 mm in diameter
    Noise at 1 meter without casing: 52.5 dB and with standard casing 45 dB
    Engine efficiency: 26% [so overall efficiency as a combustion-heated generator about 13%?]
    Design life: 50,000 hours
    Hermetically sealed: maintenance-free

    This raises a question: Would the ‘consortium of gas boiler companies (Viessmann, Baxi, Vaillant, Remeha) and Sunpower’ want the engine upgraded to twice the overall efficiency by LENR (If the engine achieved 26% overall, that would beat most IC engines and anyway it is the fuel cost that matters)?

    • Thomas Kaminski

      Nice find and thanks for the history. I seems that the Stirling Engine has quite an installed commercial base, maybe not in gross numbers, but certainly in “reduced-to-practice” technology.

      One of the interesting design options with LENR is that the heat exchanger (QX cylindrical device) could be designed into the hot end of the Stirling Engine, inside the sealed pressure container.

  • Acecrafter99

    The most efficient commercial Stirling engine I can find claims 30% efficiency. So it would seem that, due to the inherent energy loss, a 50kw Stirling engine output would require ~167kw of raw Quark output, resulting in the need for 8334 Quarks. And that presumes zero loss in the energy transfer between the quarks and the Sterling (which is not possible) resulting in the need for even more Quarks.This just makes your point more obvious. Rossi needs to begin advertising to fill a permanent position for a Senior Quark Wrangler. How much space do 10,000 Quarks require for efficient operation?

    • Thomas Kaminski

      This NASA video claims 55% Carnot efficiency (see about 1:05 into the video).

      • Zeddicus23

        The DC output from the Stirling converter might be used to charge a battery although my guess is that the NASA design is relatively low power, so it might require many Stirling converters (or a much larger scaled-up version) to get sufficient power for many applications. For a moving application, this brings up a weight issue. The claimed NASA efficiency is up to 55% of the maximum theoretical (Carnot) efficiency e = 1 – R where R is the ratio of the cold temperature Tc in degrees Kelvin to the hot temperature Tc in degrees Kelvin. For Tc = 300 K (room temperature) and Th = 1000 C = 1273 K the maximum claimed efficiency for the NASA Stirling converter would be 0.55 e = 0.42.

        • Thomas Kaminski

          NASA was looking for a means to replace the Radio-isotopic Thermal Generators, like those used on Voyager (still running after 40 years!). They had a power output of about 400 watts, and there were at least 2 of them for redundancy. As I recall, they had a hot side of 1000C (using plutonium as the radio-isotope) and a cold side worst case of about 200C. The cold side got lower in deep space without solar radiation. Here is a table of total efficiency based on various hot, cold temperatures. For Combined water heater/Electrical a good Tc is 60C (not much different from room temperature, really compared to the hot side). Can LENR generate 1500C? If so, the total efficiency is good.

          Th Tc Nasa Carnot Total
          1500 60 0.55 81.21 44.67
          1400 60 0.55 80.09 44.05
          1300 60 0.55 78.82 43.35
          1200 60 0.55 77.39 42.56
          1100 60 0.55 75.74 41.66
          1000 60 0.55 73.83 40.61
          900 60 0.55 71.60 39.38
          800 60 0.55 68.96 37.93
          700 60 0.55 65.77 36.17
          600 60 0.55 61.85 34.01
          500 60 0.55 56.91 31.30
          Typical NASA RTG
          1000 200 0.55 62.84 34.56

          NASA also developed a number of cryocoolers based on the Stirling cycle, then later
          an orifice pulse tube device. I am not sure they are in use because of the vibrational effects on sensitive chilled detectors. There are commercial lab coolers that use either Stirling, or Pulse Tube technology.

  • Buck

    It seems that Rossi has made a constructive contact. Time will tell who that is, but I hope that it is Dean Kamen and Deka Research given Kamen’s strong engineering capabilities and history of pursuing social good.


    SCHOLL Christian
    October 21, 2017 at 10:51 AM

    Dear Mr Rossi,

    Have you found a reliable 1Kw Stirling engine?
    If not, contact Sunpower.

    Best regards,



    Andrea Rossi
    October 21, 2017 at 1:04 PM

    Scholl Christian:

    We probably have found a good supplier.

    Thank you for your information.

    Warm Regards,


  • Thomas Kaminski

    See GADAB below. Good references.

  • Ori

    This just seems like another distraction from proving his claims about the latest Ecat variant.

    I doubt very much Dean Kamen is going to be interested until Rossi’s claims are proven, especially given all the negative PR from the lawsuit.

    • Steve Swatman

      I thought the lawsuit all came out in a positive light for Mr Rossi, I guess the perception of PR is different for different people, dependent on their pre-concieved bias.

  • sam

    October 21, 2017 at 2:04 PM
    Good luck for you and your team of course.
    Please allow the follwing questions on the upcoming demo:
    1.) Will a third party participate?
    2.) Will You be able to convince the skeptics, as far as you believe today?
    3.) Will it in your opinion change the LENR recognition in the media?
    4.) Is Magnus Holm still on board?

    Andrea Rossi
    October 21, 2017 at 4:33 PM
    1- yes
    2- I am an industrialist, not a phylosopher
    3- I do not know
    4- Yes, of course, as well as all the great Team of Hydrofusion
    Warm Regards,

  • He could buy Cyclone Power for pennies on the dollar.

  • sam
  • Jeannette Johnson

    Dear Mr. Rossi, you may want to look at the Proe Power Systems’ Afterburning Ericsson cycle engine instead of the Stirling Cycle engine. It is an open cycle engine, and will work with a radiator about 1/4 the size of one needed for a Stirling engine.

    • GiveADogABone

      I thought the URL a very clear explanation of the fundamental problem with combustion heated Stirling engines. However LENR heat generators like the QX are not using combustion so they do not suffer the poor overall efficiency caused by combustion and would operate well on a closed cycle.

      Rossi’s problem seems to have been finding a useful, fully developed Stirling engine that can be purchased off-the-shelf. Maybe have the answer.