Hindawi Publishing Corporation Advances in Materials Science and Engineering Volume 2014, Article ID 252879, 10 pages http://dx.doi.org/10.1155/2014/252879 Review Article New Trends in Energy Harvesting from Earth Long-Wave Infrared Emission Luciano Mescia1 and Alessandro Massaro2 1 Dipartimento di Ingegneria Elettrica e dell’Informazione (DEI), Politecnico di Bari, Via E. Orabona 4, 70125 Bari, Italy 2 Istituto Italiano di Tecnologia (IIT), Center for Biomolecurar Nanotechnologies (CBN), Via Barsanti, 73010 Arnesano, Italy Correspondence should be addressed to Luciano Mescia;
[email protected] Received 12 June 2014; Accepted 18 July 2014; Published 11 August 2014 Academic Editor: Andrea Chiappini Copyright © 2014 L. Mescia and A. Massaro. This is an open access article distributed under the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited. A review, even if not exhaustive, on the current technologies able to harvest energy from Earth’s thermal infrared emission is reported. In particular, we discuss the role of the rectenna system on transforming the thermal energy, provided by the Sun and reemitted from the Earth, in electricity. The operating principles, efficiency limits, system design considerations, and possible technological implementations are illustrated. Peculiar features of THz and IR antennas, such as physical properties and antenna parameters, are provided. Moreover, some design guidelines for isolated antenna, rectifying diode, and antenna coupled to rectifying diode are exploited. 1. Introduction power generation without increasing environmental pollu- tion [3]. Duringthelast20years,theworldwideenergydemandshave Photovoltaic (PV) conversion is the direct conversion of been strongly increased and as a consequence the deleterious sunlight into electricity without any heat engine to interfere.