The idea has been suggested that Parkhomov's latest test results may indicate that the "Rossi Effect" at best can only produce a low level of COP, no greater than 1.25. I find this line of thinking incorrect. First, I'd like to address the comment that since he is producing such a low COP now, there is no reason to believe his earlier results were valid.
1) I've heard that he has not been using his original nickel for some time. He gave so much away that the container ran out, and he had to source new nickel. This could be, although of course not certaintly, why he is not seeing the same results.
2) He is not pushing temperatures up to beyond 1300C. In his first set of tests, he produced a COP of 2.7 when he reached the temperature of 1370C. In recent tests, he has not been going much over twelve hundred degrees to avoid the quick destruction of his test system. COP goes up rapidly with temperature, often in a non-linear manner. If he were really pushing these systems, we'd probably see higher COPs.
3) The first tests he performed were in metal containers, providing more thermal insulation. In the more recent tests, the reactors seem to have less insulation. The alumina tube may or may not count, depending if it really is almost transparent to IR.
For the above three reasons, I think that we cannot just assume that he can no longer produce higher COPs. The reality is that he is going for long duration tests at low COPs to try and obtain isotopic shifts and transmutation evidence.
Now, I'd like to address several ways that the basic recipe of lithium aluminum hydride and nickel could be enhanced to produce higher COPs. To say that it is limited to a low COP is ridiculous for a number of reasons. Even if you do not accept any of the above three explanations, Parkhomov has done almost nothing to try and optimize his system for higher performance. Repeatedly he uses the same fuel mix with the same VERY MINIMAL fuel prep when there are many things he could try to increase the power output of the system.
1) Extensive Vacuuming - Although in the most paper vacuuming of the reactor is mentioned, it does not make it clear if the fuel mixture was inside the reactor. And, even if it was in the reactor, at the lower temperature the vacuuming to remove contaminants would have required many days or weeks. I think the number one thing he could do to maximize the performance of his system is to vacuum his nickel (isolated from the LiAlH4) EXTENSIVELY before testing. As far as I know, he has never done this ONCE. From non-LENR literature, I've read where it can take days at temperatures of 500C or higher to fully vacuum out the trapped gases in nickel powder. When vacuuming is performed on LENR systems, they seem to yield better results. Focardi, Me356, Andrea Rossi, and others have produced better results by vacuuming their fuel.
2) Pre-hydrogenation - I'm not convinced that hydrogenation is optimized in his system. I think that pre-hydrogenating the nickel could help boost the output significantly. Basically, by having some hydrogen already in the nickel, the hydrogen pressure from the decomposition of lithium aluminum hydride would push it in further increase hydrogen absorption. Additionally, if a hydrogen tank or a source other than lithium aluminum hydride is used, the hydrogen absorption process could be allowed to take place over a spread of temperatures lower than what is possible by the decomposition of lithium aluminum hydride. Hydrogen absorption at lower temperatures may allow for greater hydrogen embrittlement.
3) Pre-cleaning of oxides - This could take place during the pre-hydrogenation process and/or via other processes such as ultrasonic irradiation. In the active reactor via the hydrogen produced by the decomposition of lithium aluminum hydride, nickel oxide will be reduced. However, it may not be completely reduced at lower temperature ranges that might be important. By pre-cleaning the nickel of oxides hydrogen absorption could be maximized.
4) Ultra slow temperature ramp - If the LiAlH4 melts and wets the nickel, hydrogen adsorption may be hindered because hydrogen gas will be unable to contact the nickel surface. For this reason and others, I think a very slow ramp from 100C (or a little lower) to 225C at a rate of less than 1C per minute should be utilized. This will prevent the LiAlH4 from melting and wetting the nickel. Instead, it will decompose without entering the liquid phase. Additionally, heating it slowly will allow for the decomposition to happen at a lower temperature which may be important if Piantelli's optimized hydrogenation temperature of around 178 (it was somewhere around here but I don't remember exactly) is real.
5) Use of a thick IR barrier - If the active reactor body was shielded by a thick steel or Tungsten tube, less heat would escape and/or IR would be reflected back towards the fuel. This could increase the COP. In Rossi's hot cats that produced higher COPs, he utilized thick steel tubes. The original E-Cats also had thick fuel tubes of copper and then later steel.
6) Use of LiH - In Rossi's patent the use of elemental Li is mentioned. I don't think this is optimal, because it will compete for hydrogen produced by the breakdown of LiAlH4. My thinking is that in reality he probably uses LiH. This would reduce the quantity of aluminum (which hinders the reaction and reduces COP) without competing for hydrogen and increase the amount of lithium. I think a series of tests starting at five, ten, and fifteen percent LiH would be a good starting point.
7) Proper quenching and triggering - I've noticed that Parkhomov typically ramps up the temperature and excess heat suddenly appears. What might work better is to heat the reactor up to 725C and then suddenly cut off the power all together, allowing the temperature to fall all the way down to 300C or maybe even lower. This could help promote the formation of high pressure hydrogen bubbles in the nickel powder. Then he could quickly ramp up the power to maximum to provide a thermal shock. Multiple cycles of this could possibly help boost the COP.
Utilizing the BEST LiAlH4 - Some brands of LiAlH4 produce far less hydrogen than others. Me356 noticed that when he switched to Alfa Aesar brand the hydrogen released during decomposition increased dramatically.
These are only eight possible ways of improving the power of the effect. I think that there are several others as well. To suggest this basic effect is limited to low COPs when Parkhomov has done almost none of the above is ridiculous.