Within the INVESTIRE Thematic Network, 33 partners worked together in order to compare nine storage technologies for renewable energy applications. For this purpose, storage technology reports were written that presented the state of the art of lead-acid batteries; lithium batteries; double-layer capacitors; nickel-based batteries; flywheel; redox flow battery; compressed air; hydrogen-based energy storage; metal/air systems, e.g. Zn/O-2. The technology reports include detailed consideration of the technical characteristics, including thermal behaviour. Parallel tasks defined categories of storage requirements and technical criteria in renewable energy applications and conducted a detailed analysis of the economic and environmental aspects. This paper summarises the technology reports to show the differences of behaviour between the storage technologies, with particular focus on the thermal performance according to environmental and other operational conditions. The thermal characteristics of each technology are considered in the context of the storage requirements in various renewable energy applications. (c) 2005 Elsevier B.V. All rights reserved.