Radiant energy conversion

The work reported in this chapter is presented in an order slightly different from that used last year as before, purely photochemical work is followed by photoelectrochemistry, but what may broadly be termed photobiological considerations now precede discussion of photovoltaics. Some papers which neither mention nor imply radiant energy conversion, yet nevertheless seem relevant, are included. A few older papers, overlooked in last year s introductory chapter, are reported for the sake of completeness. 

We present later a classical approach (based on the macroscopic theory of radiant energy conversion) to such an analysis, which was recently reconciled with the non-equihbrium thermodynamic approach built on the definition of the chemical potential of a photon (Meszena and Westerhoff, 1999). 

Ross RT (1966) Thermodynamic limitations on the conversion of radiant energy into work. J Chem Phys 45 1-7... 

Thermophotovoltaic systems convert the radiant energy produced by fuel combustion directly into electricity. Snch systems can potentially attain high overall conversion efficiencies. Because they may use renewable as well as fossil fnels, they permit a smooth pathway for an environmentally benign method of electrical energy generation (Catalano, 1996). 

For practical purposes both these answers are sufficient if one is interested in second law analysis of energy conversion devices operated outside the atmosphere. A "heat" source of 6000K has an available energy flux which is nearly equal to its radiant energy flux. 

Photoelectrolytic and photogalvanic cells. These cells involve the conversion of radiant energy in chemical energy for converting substances but unlike the situation in (2), AG>0. The potential applied to the electrode helps the conversion. 

The radiant energy from the source must be converted into an electrical signal for amplification and measurement by the readout system. This conversion is undertaken almost universally by a photomultiplier tube. 

A) Conversion of radiant energy of one mol of photons of wavelength X to different energy units... 

Nearly all of the enzymes involved in the synthetic reactions of photosynthesis are also found in nonphotosynthetic tissue. Therefore, the unique feature of photosynthesis is the conversion of radiant energy into chemical... 

The photovoltaic devices are the most modern. They are semi-conductor or. in other words, solid-state components, and they incorporate the principle of the conversion of radiant energy directly into usable electrical power. The photovoltaic phenomenon is founded upon the basic photoelectric equation of Albert Einstein, namely ... 

Figure 11.23. Energy conversion and distribution in a typical IGCC process. RSC, radiant syngas cooler. See color insert.

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