Design and global optimization of high-efficiency thermophotovoltaic systems.

Massachusetts Institute of Technology, Cambridge, 02139, USA.
Optics Express (Impact Factor: 3.53). 09/2010; 18 Suppl 3:A314-34. DOI: 10.1364/OE.18.00A314
Source: PubMed

ABSTRACT Despite their great promise, small experimental thermophotovoltaic (TPV) systems at 1000 K generally exhibit extremely low power conversion efficiencies (approximately 1%), due to heat losses such as thermal emission of undesirable mid-wavelength infrared radiation. Photonic crystals (PhC) have the potential to strongly suppress such losses. However, PhC-based designs present a set of non-convex optimization problems requiring efficient objective function evaluation and global optimization algorithms. Both are applied to two example systems: improved micro-TPV generators and solar thermal TPV systems. Micro-TPV reactors experience up to a 27-fold increase in their efficiency and power output; solar thermal TPV systems see an even greater 45-fold increase in their efficiency (exceeding the Shockley-Quiesser limit for a single-junction photovoltaic cell).

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