A Correction Makes A Difference in Cat and Mouse Discussion

Here’s an important correction, I think, that pertains to the discussion we have been having about the cat and mouse.

On the Journal of Nuclear Physics, Andrea Rossi wrote to Joseph Fine:

Our basic module is made by an apparatus in which we have 2 components: an activator, which consumes about 900 Wh/h and produces about 910 Wh/h of heat. This heat activates the E-Cat and then goes to the utilization by the Customer, so that its cost is paid back by itself. This activator stays in function for the 35% of the operational time of the syspem of the apparatus. The E-Cat, activated by the heat of the Activator, works for about the 65% of the operational time, producing about 1 kWh/h without consuming any Wh/h from the grid.

(emphasis added)

On vortex-l, Patrick Ellul wrote in reference to this post:

I thought he might have done a typo, and mean 10 kWh/h so I emailed him to ask.

He confirmed that it was a typo, and he meant 10kWh/h for the ecat, just like it has always been.

If that is the case:

0.91 * 35% of the time = 0.3185 kWh/h
10 * 65% of the time = 6.5 kWh/h

total output = 6.8185 kWh/h
input = 0.9 * 35% of the time = 0.315 kWh/h

COP = 21.65

So, taking into account this correction and rounding the numbers, the way I see it is that the output of the Cat is about 10 times the output of the mouse, and it is turned on about twice as long as the mouse is on, so you are going to get approximately 20 times as much energy out as you get in.

Regarding the activator ‘paying for itself’, I now think that Rossi means that the customer is paying for the input energy anyway (electricity or gas) and it ends up being used in the output mix, and with the E-cat in place that input energy is multiplied by about 20.

That’s my current thinking on the matter — could change with more information.



  • Roger Bird

    I thought that the mouse was inside of the cat, no visual pun intended.

  • Ron

    Everything I have read over the last two years indicates the output is 10KW but that aside, saying the “mouse” control pays for itself is not qualitatively correct for electrical input. The output in heat may be the same but electricity is in a primary useful form while heat used to generate electricity is subject to losses and conversion of maybe 40%. The electric output efficiency would then be 364W/900W which hardly pays for itself. This might be higher if it is a CHP unit.

  • RNBE

    The last Rossi’s comment that confirms that the effective overall energy gain (call it COP if preferred) is (65+35)/35 that is about 3:

    Andrea Rossi
    May 15th, 2013 at 7:44 AM
    Dear Dr Renato Estri:
    Perfect. You got exactly the core of the issue.
    Thank you. To the readers: please read carefully this comment of Dr Estri: it explains exactly in a short matrix the COP issue.
    Warm regards,

    May 14th, 2013 at 11:39 PM
    Dear Andrea Rossi,
    I try to give a contribute to the debated COP matter about the
    Tiger-Activator new configuration.
    Should this table resume in numbers the correct interpretation
    of your answers ?
    % Time / COP / Pow In / Pow Out
    65% / 200 / Zero / 100KWh
    35% / =1 / 100KWh / 100KWh
    Thank you very much in advance

    • RNBE

      In my calculus I supposed that in the matrix “kWh” is a mistake of who wrote the comment and the meaning refers to a power that is “kW”.
      If not, being the data “energy”, Bob calculus is those right and the overall COP is just 2.

      In any case who continue to speak and to wrote in this Blog of an overall COP of tents or hundreds is just because he want to make a mess.

      • Omega Z

        COP is the Value of Energy supplied dived into the Power Out in a Specified period of time.
        Mouse uses 900 watts-35% of 1 hour period.

        In=Total Mouse Input for the hour is 315 watt hours.

        Out=10Kw E-cat Power Out 10,000 watts per hour.


        Your 65/35 is just the time the mouse is off/on

        • Roger Bird

          31.746031746 Not bad for pollution free and almost free FOREVER.

  • Joel C.

    May 14th, 2013 at 11:39 PM
    Dear Andrea Rossi,

    I try to give a contribute to the debated COP matter about the
    Tiger-Activator new configuration.

    Should this table resume in numbers the correct interpretation
    of your answers ?

    % Time / COP / Pow In / Pow Out
    65% / 200 / Zero / 100KWh
    35% / =1 / 100KWh / 100KWh

    Thank you very much in advance

    Andrea Rossi
    May 15th, 2013 at 7:44 AM
    Dear Dr Renato Estri:
    Perfect. You got exactly the core of the issue.
    Thank you. To the readers: please read carefully this comment of Dr Estri: it explains exactly in a short matrix the COP issue.
    Warm regards,

    • Bernie Koppenhofer


      • guga

        Bernie, aren´t you supporting the idea that the HotCat has a high total COP and produces free energy?

        I just don´t get why you are so happy about this post. I mean, here it is made clear that you need 100kWh of input for around 300kWh of output. And no word that the put out heat could be used to trigger the reaction.

    • sparks

      So there it is at last: COP=2.857

      Average power in: 100 x .35 = 35 kW
      Average power out: 100 x 1 = 100 kW
      COP: 100/35 = 2.857


      • Bob

        No. The table is showing TOTAL energy in and out. You do not then reduce these amounts by applying the percentage reductions.
        If the units quoted were in kilowatts rather than kilowatt-hours then you could apply the percentage to the equation and that would be valid, but kilowatt-hours is a measure of a quantity of energy in much the same way as you would measure a bucket of water.
        So the total ‘bucket’ of energy input is 100 kilowatt hours regardless of what the percentage of ‘on time’ was. (that is, how long the tap was turned on)
        You cannot say that here is the bucket of water but because I only had the tap turned on for 35% of the time I only have to pay for 35% of it. The bucket has 100 kilowatt-hours in it so you have to pay for ALL of it.
        That is, it all has to be included in the equation for the COP calculation. 100Kwhrs in, 200 Kwhrs out -> COP = 2

        • sparks

          Well, yes, you are correct that they have their units confused again. Their so-called Dr. Estri uses labels “Power in” and “Power Out” and then reports KWH, which is energy. I didn’t notice that — going too fast I guess. Nice catch. How could this Dr. Estri possibly be a PhD and make such a fundamental mistake when constructing this table? And I guess Dr. Rossi was going too fast, just like me, and missed it. So we still have some ambiguity regarding the actual COP, but several data points are favoring a COP in the 2 to 3 range now.

          • Bob

            With due respect to the few very clever PhD’s, most of them are pretty ordinary people who simply put the time in towards getting the qualification and are no better at arriving at a correct conclusion than the average Joe.
            I have seen some seriously and obviously wrong conclusions arrived at by holders of PhD’s. Don’t be intimidated by their letters.

            • Roger Bird

              I will agree only to the extent that PhDs cannot do perspective changing any better than anyone else, perhaps even less well. Any problem that requires a change in perspective is going to be just as much of a challenge for PhDs as for anyone else, perhaps because PhDs have so much invested in an old perspective.

              But most of the PhDs here have changed their perspective to “I don’t know” or “I believe in Rossi” or something like that, so I am happy that they are here.

            • sparks

              Bob, FWIW in fact I have those same three letters after my name, earned in 1982 in Electrical Engineering, and all I can say in retort to your assertions is … ABSOLUTELY RIGHT! So many times I have made the same point, that is, it sometimes (depending upon the institution) comes down to how long they put in the time and pay the tuition. When I hire, I almost invariably go for the Master’s degreed candidate over the Ph.D. candidate.

      • Not being a PhD, I still would like to list here some units to be used in questions to get rational answers:
        h = unit of time in hours
        (H = unit of inductance in henries)
        k = kilos, thousands of
        (K = unit of temperature in kelvins)
        W = unit of POWER in watts
        Wh = unit of ENERGY in watt hours
        Getting an answer ‘yes’ after asking whether ‘Pow in’ is ‘100KWh’ won’t help much, as we are witnessing here.

        • Roger Bird

          They seem right to me. Roger Bird, PhD in Practical Parenting.

  • buffalo

    yes this is why i suggested a hunt for alternative to nickel.perhaps tungsten,or platinum,cobalt etc.i suppose rossi has tried these but maybe he missed a spot or observation error.

  • andreiko

    The main problem with LENR seems to me (on/off) has hopefully Dr. Rossi and his team found a suitable solution for here.

    • Daniel

      The main problem with the e-cat is that too few people believe in it, and they still may be right unfortunatelly. The ultimate proof is still not after a few years of web discussions. May 2013, should we get the 3rd party report or not? If it is still not here in say October but only “Rossi says proofs”. Will you still believe in it then? Im still a believer but probably not in October with no 3rd party results.

  • Lu

    It appears to me that Rossi is avoiding an explicit clarification of whether the reactor is a 1K or a 10K component. There has been plenty of opportunity to do so and clearly Rossi has given mixed messages about whether it is a 1K reactor or 10K reactor.

    For 10K all we have is Patrick Ullel’s claim that that Rossi said it was a typo in what appears to be a private email(not saying this is not true) and perhaps the perplexing consequence that the new COP would be less than the old COP. But for 1K we have numerous Rossi statements and readers posting queries 1K with no correction by Rossi. Also for for a Hot Cat the charge is supposed to be about 20 grams but Rossi says his reactor has 2-3 grams which if it scales would make it a 1K reactor.

    Also interesting is that Rossi did not provide a COP for his new two component apparatus when the calculation is quite straightforward once the basic performance of the parts are known which he has given out. It looks to me Rossi has misspoke somewhere along the line or he is trying to hide the decrease in COP to 3.

    • Omega Z


      Rossi has answered, but the question has become repetitious and he says to reread his answers.

      The Mouse is 1Kw, The E-Cat is 10Kw, The Hot-Cat is 10Kw, And the New Hot-Cat is 100Kw.
      Both the 10Kw & 100Kw Cat Reactors will be activated by the 1Kw Mouse/Activator.

      The 10Kw will produce a COP of 20 to 30.
      The 100Kw will produce a COP of 200 to 300.

      Here is the Real Question. Exactly what does the Mouse Bring to the Table. No pun intended???

      I have a Good Idea & My question to Rossi or rather My thoughts on this in My Question to Rossi has apparently Gotten me Banned From JONP. I’ve made several posts on JONP since this 1st went to neverland & now they all go to neverland. Not Moderation. Just GONE…

      • Miles

        Well said. Apologies for my ignorance, wasn’t the E-Cat “10Kw” supposed to have a COP of 6? Where did the 10Kw come from?

      • Lu

        I think you have it wrong. Read Rossi’s and my posts more carefully.

      • Bernie Koppenhofer


      • Gerrit

        To me it seems that from day 1 Rossi has had difficulty in controlling the system.

        That’s why the “self sustained” mode was always a bit tricky. The COP was always 6, because although it could be higher, the stability would decrease.

        The mouse brings stability to the system, that’s all.

        It’s either that or Rossi is making the story up as we go.

      • Bob

        Omega Z, it appears you have it sooo wrong that even Rossi has given up and consigns your posts to the trash can. 🙂

        Almost all the things you said here are not what Rossi said.
        Me-thinks your wild enthusiasm has got the better of you.
        From what ‘Rossi says’ we can deduce the folowing;-

        The mouse has a power inpout of 2.5 kilowtts but because it is only on for 35% of the time it averages out over each hour to 900 watts input power.
        The ecat was reported as being 10 Kw but all tests showed at best it was 5 Kw.
        The hot cat was originally thought to be around 5 Kw but has now been reported by Rossi as being 1 Kw, even though the figures he supplies indicate a power output of 2Kw. (I can’t explain that without being banned)
        The new hotcat is inded reported as being a 100Kw unit but this will almost certainly be a pack of 1Kw reactors sufficient to make up the 100Kw. I am certain it will not be a 100Kw single reactor.
        The 10Kw, which is actually the 1Kw unit, will have an overall COP the same as the one tested, for which the report appears to have been delayed well past the expectation date, but my guess is now 1.02
        The COP for the 100Kw unit will be the same as for the 1Kw unit, because it consists of a number of them. So far, from the numbers given, this is seems to be around 2, but could also be 1.02.

        And in reply to the question, ‘What does the mouse bring to the table?’
        The COP of the activator (mouse) has been said by Rossi to be 1.02 which is unbelievably accurately defined for a measure which is obtained by thermal radiation measurements.
        For a spherical body hanging in a vacuum, well away from all other objects, and using top shelf measuring equipment, I could only just believe it, but for a cylindrical device in a laboratory atmosphere it would be difficult to measure this to an accuracy better than plus or minus 5%. And I would count that as being impressive.
        I can only conclude that this figure of a COP of 1.02 was arrived at by way of the results of the third party independent report, either the latest one or the one which was scrapped in November last year. They may well have thrown enough high tech eqipment at it to come up with a measure so closely defined.
        What I see now is this 1.02 figure being weaved into the picture by way of saying it is only for the activator and does not apply to the overall reactor. Once that is well established and accepted we might see the release of the report.
        It’s worth noting that we never heard a word about the two stage cascaded design until after the shelving of the November report and after the next independent report was completed. I was always puzzled why this information was released when all other information as to the internals of the reactors was strictly off limits.

        • Omega Z


          All Rossi’s posts can be found here on a single page.


          The Mouse/Activator is 1Kw.
          Depending on E-cat Model. 10Kw/100Kw/Gas/Elec.

          Cats are the Reactors. 10Kw, 100Kw

          All Cats have their own mouse.
          There is no feed back/loop from Cat to Mouse.

          Most of what is discussed her at present is within about the 1st 200 posts.

          • Bob

            As I said in a separate post, that’s the way the conversation is now going in the last 200 posts to the Rossi blog, but that is not how it was prior to the testing.
            We will be asked to accept the device which was tested was only the 1kw mouse which has a COP of 1.02
            Before the test the conversation was that it was a 3 to 5 kw hotcat under test.
            Anyway, we shall see, or not, as the case may be.

    • Bob

      Rossi clearly stated on his blog more than once that it was a 1Kw reactor.
      In response to numerous questions he has replied a number of times that what he wrote is correct.
      The original specs of 1kw are still clearly on his blog. He has not changed it.
      The 1kw specification is also consistent with the statement that the reactor subject to the independent report, (still not released) was 1Kw.
      The only indications that it was anything greater than 1kw came in answer to other peoples posts to his blog asking if it was a typo and did he mean 10kw. I see this as wishful thinking only.
      He probably doesn’t read them carefully and just fired off a random answer.
      Any reply that it was a typo and the output was 10kw is inconsistent with all his other clear statements and it is inconsistent with what is still reported on his blog.

      To keep things clear, only take what Rossi says, not what others say and then he approves, unless what he approves is clearly the same meaning as what he originally said. Anything else ends up in ‘Alice in wonderland’ and since we are already half way down the rabbit hole there is no need to rush the journey.

      So, the reactor output is 1 kilowatt.

      Furthermore, there have been some wildly high estimates of the COP based on what Rossi didn’t say.

      Here’s what Rossi said,
      The activator consumes 900Wh/h and produces 910Wh/h.

      He said in an earlier post that a test ran for 100 hours and these figures of 35% and 65% were the average over the 100 hours.

      On average, the activator is ON for 35% of the time.
      during which time the ecat is OFF.
      This means that the heating element must have a rating of 900/.35 = 2571 watts, and is only turned ON for 35% of the time which makes the average quantity of energy input equal to 900 Watt-hours in each and every hour of operation.

      He also said that the output energy during this ON period is 910Wh/h.
      So, considering only the activator, every hour, the ‘bucket’ of energy in is 900 Watt-hours and the bucket of energy out is 910 Watt hours. (I might add, he would need some very accurate measuring equipment to measure radiant energy to that accuracy.)
      However, in the same one hour period when the activator is OFF, the ecat produces 1Kwh (1000 watt hours) of energy.
      This makes a total energy output for each and every hour, 910 watt hours from the activator PLUS the 1000 watt hours from the ecat.
      910 +1000 = 1910 watt hours total energy output divide by total energy input of 900 watt hours = 2.1222
      The COP for the overall device is therefore 2.12
      Going on what ‘Rossi says’ that’s what it is.

      The talk about infinite COPs completely ignores the fact that for every hour of operation you have to plug in 900 watt hours of energy.
      If you don’t it stops working. Maybe catastrophically.

      You can’t claim you have invented a car which displays infinite efficiencey because you have discovered it rolls down hills. Somewhere in the process , someone had to push it up the hill.

      • guga

        I think I must have written this post above under the name Bob last night in my sleep, because I agree so much with it. 😉

        There is too much wishful thinking going on here.

        But I believe exact COP calculations make no sense, we have too little information. The current total HotCat COP seems to be around 2, but might also go towards 3 (depending on how fast this on and off happens).

      • Shane D.


        I even understood that… thanks. By the way, the first hotcat report late last summer by Rossis’ side-kick also showed a COP of 2.2.

        What a coincidence.

  • atanguy

    Well,at this point I will be happy even with a COP of 3 if it is real,it can only increase in the future.

  • Kim

    I’m still not confident that the module is
    10 Kilowatts.

    If it helps he did state that a 100 KW
    unit is .2 cubic meter or a cube 2ft3

    That would account for 10 of the 10Kw


  • Arnie

    I wrote the following comment, but was “spammed”

    Dear mr Rossi and all readers: I am sorry to come back to this subject once more, but despite all attempts to explain I am confused.
    Mr Rossi wrote:
    “The E-Cat, activated by the heat of the Activator, works for about the 65% of the operational time, producing about 1 kWh/h without consuming any Wh/h from the grid.”

    Does the E-Cat really only produce 1kW during SSM? Or is that a typo? In that case:
    Operation for 1 hour:
    Input 0,35h*900 W=0,315 kWh
    Output 0,35h*910 W=0,319 kWh
    Output 0,65h*1000W=0,65 kWh
    Total output=0,969 kWh
    So this gives a COP of only 3,08. This makes no sense, since the first version had a COP of 6.
    If the E-Cat output during SSM would be 10 kW, the COP would be 21,7
    Please help me out here.
    Kind regards

    I was pretty sure it had to be a typo anyway, but then Rossi wrote:

    Andrea Rossi
    May 14th, 2013 at 6:28 AM
    Dear Stefano:
    Yes, you got it.
    Warm Regards,
    May 14th, 2013 at 1:50 AM
    Dear Dr. Rossi
    Thank you for your effort in keeping alive the comunicatikn with your readers. In practice I understand that the system overall consumes gas or grid power for the 35% of the time but that energy is returned in any case to the costumer. And in that time the system has a cop of about 1. In other words the real gain is in the 65% of the time with a large production of energy without consume. Is it correct.

    This confirms a COP of about 3 without any room for misunderstandings, I am afraid

    • Redford

      Nope. As written in the very news you’re commenting, there’s a type. Global output is 10 Kw, not 1. You may want to read the article you’re actually commenting…

      • Arnie

        That article is based upon an email that we can’t even know for sure exists. Rossis answer in jonp at the other hand is there for everyone to see

        • Redforf

          I get you but nonetheless, put as it is, the above post makes no sense for an external reader. It reallh serms line you did not read OP. Else you would have directly discussed the validity of the typo explanation.

          BTW I hope you paid more attention pn JNOP and Rossi’s posts than uou did here :-/

    • Bernie Koppenhofer

      If you did ask “If the E-Cat output during SSM would be 10 kW, the COP would be 21,7” and Rossi confirmed, what is the problem,why do you think he confirmed 3COP?

      • Arnie

        That’s the point, he did not even reply to my question, but confirmed Stefanos question, that implies a COP of about 3.

  • Steven N. Karels

    With the Activator COP of 1.02, it makes little sense to use it instead of an electrical resistance (COP = 1.0) unless there is another reason to do so.

    • Ron Stringer

      True, but the electrical resistance wasn’t able to make the ecat run in ssm all the time, hence the lowered COP. The activator is doing something the resistance heater wasn’t able to do for some reason.

      • Bernie Koppenhofer


    • Andre Blum

      yes, that is a very interesting question.

  • clovis

    Hi everyone.
    My take is this, the big cat has to maintain a certain temp if not it will overheat and melt the nickel, or not enough heat and it shut down,
    So the mouse, is just a small e-cat that holds the larger cat at that particular temp , when you turn the big cat off you lower the temp of the E mouse just enough to make the big cat shut down, but the e mouse still retains enough heat to restart the big cat when necessary. the e mouse is hooked to the grid for start up power only for the E mouse to use if needed. —- you guys see anything wrong with this scenario.

    • LENR4you

      The main task of the activator-cat is to produce a sorte of X-rays for the hot-ecat to trigger the reaction!

      • Glenn

        Where did all this talk of X-rays being emitted by the Activator come from? Did Rossi say this?

        I’m not trying to cast doubt on what you’re saying, I’m just looking for a reference because I’m trying to put the pieces of the puzzle together, like everyone else here.

      • Omega Z


        YOU are on the Right Track.
        The Mouse is doing More then just providing Heat.
        The Heat is necessary, but it’s adding something else in the Mix.

        • NJT

          As I have stated before, we do not know everything and that is fine, until Mr. Rossie gets his IP protection (here in USA and worldwide) can you blame him for wanting that first? – contact your congressperson and complain about the treatment he and others researching LENR receive from the US Patent Offices and our Department of Energy…

          • you can file a chinese patent, or a EU patent. they seems more open, and through convention you will be protected soon.

            what make many patents rejected seems mostly that they are not precise enough to allow someone reasonably competent to build the machine.
            Rossi’s patent is horrific about that.
            Celani, Piantelli, Godes, got their patents. even some unrealistic patent get accepted. they were all precise enough to build something.

          • Bernie Koppenhofer

            Right, it is possible Rossi was getting pretty close to revealing something he did not want to reveal for trade secret and patent reasons, so he cut off all answers on the subject.

        • ah, more logic now…

          Quickly thinkin I see two things that the mouse (if not another Rossi red-herring) may do :
          – first is providing a dynamic compensation to stabilize the tiger, like adding negative feedback, with some phase-shift, or non-linear feedback, or inertia .
          – the second is providing some radiation to activate the reaction

          a COP of 1.02 is not worth replacing a resistor with a LENr reactor.

      • Damien

        Great hypothesis.

        I was trying to figure out why he would bother using the mouse at all.
        With a COP of 1.02, it wouldn’t be economical to include it in the design purely to provide heat, when it would only be slightly less energy efficient and heaps more space efficient to use a plain heating element.

        I think you’re on the right track.