The 12% efficiency quote seems to originate in an interview with the authors. I read the actual paper,[1] and it only mentions a projected efficiency of 2-3%.

The 12% efficiency quote seems to originate in an interview with the authors. I read the actual paper,[1] and it only mentions a projected efficiency of 2-3%. You are right that there simply isn't enough energy in the near-infrared to achieve a 12% efficiency. As in a lot of scientific reporting, it's hard to know whether the journalist misinterpreted the authors, or if the authors were indulging in a bit of hyperbole to promote their work. =) The device described in the paper is intended for energy scavenging rather than as a competitor for standard opaque cells. The idea is that, since you already want an anti-reflective coating to block IR light and minimize your air conditioning bill, why not use a coating that also incorporates a solar cell? [1] http://apl.aip.org/resource/1/applab/v98/i11/p113305_s1?bypassSSO=1 http://apl.aip.org/resource/1/applab/v98/i11/p113305_s1?bypa...