Use of plastics in solar energy applications

A discussion of the state-of-the-art on the use of plastic materials in solar energy applications is presented, with particular emphasis on their suitability and durability. The availability of plastics in many types and shapes ( including sheeting material, films and foams) accounts for the wide range of current and potential applications in solar energy installations. Consequently, actual and potential uses of plastics include: covers (glazings), honeycomb structures and housings for flat-plate collectors; reflecting surfaces, optical lenses, shells, structural and support members for solar concentrating collectors; and insulation and piping. The plastics that have been discussed in this article in relation to their use as components in solar installations include poly( methylmethacrylate) (PMMA), polycarbonate (PC), glass fiber- reinforced polyester (GRP), poly(vinyl fluoride) (PVF), fluorinated ethylene-propylene (FEP) copolymer, poly( ethylene terephthalate) (PET) and various foamed plastics. The aging behaviour of most of these plastics has been widely studied for normal outdoor exposure and in artificial weathering devices, and are thus briefly described here. Very little information is available, however, regarding their short-term performance under actual service conditions in solar energy installations; none has been reported on their long-term durability. Plastics have various degrees of flammability and therefore special care should be taken using materials with adequate fire resistance and/or appropriate design in applications where a fire hazard may exist.Pr\ue9sentation des mat\ue9riaux plastiques les plus r\ue9cents utilis\ue9s dans le domaine de l'\ue9nergie solaire, en consid\ue9rant particuli\ue8rement leur valeur pour l'usage pr\ue9vu et leur durabilit\ue9. L'existence de plastiques de nombreux types et de nombreuses formes (notamment des feuilles, des films et des mousses) fait qu'ils ont beaucoup d'applications actuelles ou potentielles dans le domaine de l'\ue9nergie solaire. Parmi les usages actuels ou potentiels des plastiques citons: les couvertures (vitrages), les structures en nid d'abeilles et les logements des capteurs plans; les surfaces r\ue9flectrices, les lentilles optiques, les enceintes structurales et les \ue9l\ue9ments de soutien des capteurs solaires \ue0 concentration; et l'isolation et les canalisations. Les plastiques consid\ue9r\ue9s sont les poly(m\ue9 thylm\ue9thacrylate) (PMMA), les polycarbonates (PC), les polyesters renforc\ue9s de fibres de verre (PRF), les poly( fluorure de vinyle) (PVF), les copolym\ue8res flour\ue9s \ue9thyl\ue8ne- propyl\ue8ne (FEP), les poly(t\ue9r\ue9phthalate d'\ue9thyl\ue8ne) (PET) et divers plastiques en mousse. On d\ue9crit bri\ue8vement le comportement de ces plastiques au vieillissement.Peer reviewed: YesNRC publication: Ye