This paper describes a new photovoltaic floating cover system for water reservoirs developed jointly by the company CELEMIN ENERGY and the Universidad Politecnica de Valencia. The system consists of polyethylene floating modules which, with the use of tension producing elements and elastic fasteners, are able to adapt to varying reservoir water levels. A full-scale plant located near Alicante (Spain) was built in an agriculture reservoir to study the behaviour of the system. The top of the reservoir has a surface area of 4700 m(2) but only 7% of such area has been covered with the fixed solar system. The system also minimizes evaporation losses from water reservoirs. (C) 2013 Elsevier Ltd. All rights reserved.