Energy harvesting in roped elevators

In civil buildings, large part of energy consumption of common service is related to lift apparatus operations. Considering the huge diffusion of roped elevators and their reciprocating operating mode, a critical evaluation of energy streams has been done using an accurate model specially developed. Thus, a retrofit kit has been studied and designed able to store the energy during the generating mode of the electrical machine and to recover it back in motor operation. Finally, a comprehensive evaluation of the saved energy parameterized with the numbers of passengers and lift duty cycle is presented, as well as the kit cost estimation and pay-back time.