I read the article and it definitely states that the electricity is generated by a temperature differential. If you immerse the cell within a constant temperature environment, it appears as if you can not get any electrical energy. This is consistent with what I have seen in the past where two temperature sinks are required.
Dave -----Original Message----- From: David Jonsson <[email protected]> To: vortex-l <[email protected]> Sent: Tue, Jan 29, 2013 8:29 am Subject: Re: [Vo]:100% conversion of heat to electricity with thermophotovoltaics So what is wrong with the Wikipedia article? What I mean is that regardless of how efficient the thermophotovoltaic is there is no other way for heat-energy to escape the enclosure except as IR-light converted to electricity. With this forced arrangement how can electricity generation be anything except 100 %? There is no Carnot cycle since energy flows from one end to the other. There is no cycle involved. David David Jonsson, Sweden, +46703000370 On Sun, Jan 27, 2013 at 9:31 PM, Jones Beene <[email protected]> wrote: David, You are possibly misreadingthis article. It is poorly written to begin with. Carnot efficiency affectsall heat engines in a similar way. Moreover, it is a basic limitationwhich deducts “off the top” so all other inefficiencies deduct from the lowernumber. From:David Jonsson Hi I have imagined using thermophotovoltaics to produce a highly efficientconversion from heat to electricity. Imagine having a heat source in a very thermally wellinsulated container. In the same container there is a thermophotovoltaic cellconverting the heat radiation into electricity. Wouldn't a cell like that be very efficient? Whatstops it from being 100 % efficient, or having its efficiency reduced only byleaks in the thermal insulation? Even if the Carnot efficiency http://en.wikipedia.org/wiki/Thermophotovoltaic#Efficiency is low it doesn't affect the total efficiency. Theemitter will always be hotter than the converter, since the converter convertssome of the heat radiation. There will always be some efficiency. Increase ofdark current, as Wikipedia mentions as a reason for efficiency decrease athigher temperature, should be the same in both directions in the converter andcould not lower efficiency. Either efficiency could be higher or the explanationsof the efficiency lowering effects are wrong. Best would be to build a device and see what willhappen. David
