In reply to David Roberson's message of Fri, 5 Feb 2016 01:50:14 -0500: Hi, [snip] >I suppose the question is; How inefficient does the solar cell array become >when the device is throttled back significantly? Since all the power >eventually becomes radiated, the black body temperature must be adjusted >downwards as the required output power is reduced. Since the radiated power >varies as the 4th order of the temperature, halving the temperature would >cause the radiated power to drop by a factor of 16. How well would the array >operate at that black body temperature?
You can also look at it from a different point of view. The power output from the solar array can be reduced significantly with only a minor reduction in power output from the device. However this does imply a significant shift in the balance between electrical and thermal output. > >Also, would the silver remain a vapor at one half the standard output >temperature? I'm not sure that it's a vapour now. It may be burning in the air producing Silver oxide (unless he's running under an inert gas). If it is a vapour, then it would probably condense on the cooled inner walls of the chamber anyway. >If not, the device may not work at that operating point. Also, it's only the spark *rate* that varies. The energy released per pulse should stay the same (more or less), which implies that the temperature in the immediate environment of the spark should remain the same for the duration of a reaction. Only farther way near the walls will it average out. > >And, the power available to run the silver furnace and pump might become a >significant proportion of the total received from the solar array at that >lower power level. If so, a lot of heat would be emitted for a relatively >small amount of electrical energy. Yes, this is probable. > >I suspect that a large amount of engineering is going to have to take place >before this product can become commercial. At least Mills might have a good >start. > >Dave Agreed. BTW I pointed out to Mills in private email, that by using the UV/x-rays directly (i.e. without the tungsten plate) he should get much higher quantum efficiency from the solar cells. I.e each high energy photon should indirectly create multiple free electrons. That would mean that the currently accepted response curve of the cells could be wrong, i.e. instead of dying off at shorter photon wavelengths, there may be a new peak at even shorter wavelengths. E.g. if the photon is 100 eV, and the ionization energy of a solar cell atom is about 10 eV, then he should get roughly 10 electrons-hole pairs per photon. This may mean that pretty much any solar cells would work, irrespective of their normal optical spectral peak. I.e. if they normally react to long wavelength photons, then they will simply have a lower electron/hole formation energy, which means that the number of electron/hole pairs per photon increases. There is however a downside. Such high energy photons/electrons, tend to shorten the life-span of the solar cells, so it may be necessary to use a self-healing semiconductor. Regards, Robin van Spaandonk http://rvanspaa.freehostia.com/project.html
