Or, you could do it. Read the report. Look at the calibrations, and do the arithmetic. You will see the calorimeter can measure 150 mW with confidence.
Jed, let me spell this out so that there is no misunderstanding.
(1) I'd expect this setup to be much more accurate than Mizuno's, obviously.
(2) I'd expect the calorimeter accuracy to be much better than the transient detected (9W)
(3) I don't know whether the accuracy is higher than the 1.9W continuous excess you note (2% accuracy).
(4) I strongly question your accuracy of 150mW (0.15% accuracy). That is very high for any calorimetry.
(5) More generally I don't have enough info from your link to do an error analysis.
The link is a lot of pictures with a few numbers. The only error estimation I can find is 0.01C as the temperature measurement accuracy. You may be better off than me able to read the Japanese.
For error estimation here we would also need:
- Input power measurement error (?)
- Sensitivity (temperature change / W) (can be worked out from data)
- Second order effects (change in calibration with room and sink temperature)
I think you are confusing power out resolution - which I agree is very high here, with accuracy. Anything that might change between calibration and active runs and affects the result degrades accuracy. That is power measurement drift and resolution, voltage measurement drift and resolution, room temperature, water inlet temperature, etc. This setup is relatively insensitive to room temperature change because of the water cooling and the differential temperature ,measurement, but even so that does not mean there is no sensitivity there.
PS - i mention resolution because many of the presented figures have a 3 digit resolution as displayed, which worst case leads to +- 0.5% resolution error.