Abd in his latest blog post has a good point: "gauge pressure does not accurately tell us the boiling point of water." (real quote)
As a reminder, the following quote from the test plan implies that Penon at least initially chose a probe reporting absolute pressure.:
"Probe for steam pressure measurement PX 309—100A5V"
If we add Abd's insight to that, it does seem logical not to choose to measure gauge pressure if you are trying to show whether water is above its boiling point or not.
Can we assume Penon made the best choice? At least we know he did initially, and I don't see why he would switch to a worse option afterwards.
A conversion from gauge pressure to absolute on the fly also wouldn't make sense - imagine removing 14.69 psi or 1.01 bar from your measured value. That's just weird.
The ERV data that we have seen so far doesn't specify gauge or absolute; it just says "steam pressure(bar)".
Murray in exhibit 5 says "the steam pressure was reported (for the entire period) to be 0 kpaG"
Note that the unit here is kpa and not bar as in the report. Also this seems to come from an earlier report, probably after 9 months as implied below in the same part of exhibit 5:
According to the data you have reported, the conserved mass flow rate of the system from February to November 2015 was on
average 33,558 kg/day (1398 kg/h) and the temperature of the water and steam were on average 68.7o C and 102.8o C, respectively."
So, the 3rd quarter report either explicitly say "0kpaG" or did it say "0 bar" as the final report does? We don't know.
Did Murray make an assumption about the pressure being gauge? This is possible, because 0 absolute would be a such a prespoterous value.
We know from the test protocol that
During the 350 days of operation, the ERV will visits to the plant with a frequency approximately four months"
So Penon wasn't the one writing results down daily. Which means it is possible that whoever was writing results down (Rossi?) could have though he had to report "0 barG" when the actual value was 0 bar abs. Since someone else was doing Penon's work of writing down values, it is possible that they weren't questioning why the pressure was always at 0.
The pressure transducer chosen by Penon reports a voltage of 0 to 5V depending on the absolute pressure value. 0V for 0 psi, 5V for 100 psi. http://www.omega.com/Pressure/pdf/PX309-100mv.pdf
Note that maximum operating temperature is 85C. I'm not sure how the transducer would be affected by higher temperatures.
Putting all of this together, I believe at this point that the most likely hypothesis is that the pressure transducer was not working at all and therefore reporting a value of "0V ~ 0 bar abs" the entire time. Rossi maybe thought this meant 1 atm and was satisfied. Murray didn't consider that possibility and therefore assumed 1 atm as well (or maybe the report said 0kpaG somewhere). Penon was only there once every 4 months, why would we expect him to care or pay attention to such details?
If true, it means that the whole test is inconclusive and Rossi supposedly spent 16 hours/day in his shipping container for nothing.
Rossi seems happy not questioning a COP of 100 when he had much lower COPs initially. Could he also be deceiving himself? The optimistic part of me wants to believe that maybe he does have a COP of 1<x<10 but somehow got led to believe that he had a COP=100 because of a poor test setup.
Of course IH questioned a COP that was >10 times more what was expected. That's a red flag in itself.