Background Lead-acid batteries have a life of 3-4 years. In most European countries, batteries are then recycled, at which time there is a risk of pollution. These risks can be reduced by increasing the utility of, and operational options for, recycled batteries. Objectives The PNEUMA project aimed to eliminate the use of lead-acid batteries in mobile telephone radio-base stations by demonstrating the feasibility of innovative back-up systems, using stored compressed air, that were to be tested in four demonstrator units. These were expected to guarantee at least two hours of service to the transmitting apparatus and so eliminate the battery stack in the energy station. The new approach was forecast to be: cost compatible with battery solutions; have low maintenance; remain compatible with lead-acid batteries; and be based on proven technology. Results After having met several problems concerning the mechanic equipment, which slowed down substantially the development of the four pilot prototypes, the project finally succeeded in assembling the four machines and sent the most promising one to Spain for a testing period. However, in addition to the number of difficulties experienced by the project during implementation, also key information lacked at project closure, regarding issues such as effectiveness, impact and sustainability.