Emission free compressed air powered energy system can be used as the main power source or as an auxiliary power unit in vehicular transportation with advantages of zero carbon emissions and improved the overall energy efficiency of the integrated energy system. This work presented a detailed technological development of compressed-air energy systems. The studies on compressed-air powered powertrain in transport sector are summarised including the design of new valve technologies, prototype developments, and integration of the system. Furthermore, compressed-air based hybrid technologies using different pneumatic hybridisation methods are comprehensively presented aiming to provide in-depth insight on the advantages and limitations of different pneumatic hybridisation. The opportunities and challenges for the compressed-air based technology in transport application are discussed. It can be expected the transformation of energy systems to a cleaner and more sustainable future would promote the technological development and implementation of Zero-Emission compressed air solutions.