This project will deliver a production-feasible waste heat recovery system for urban commercial vehicles, which offers life-cycle CO2 savings of up to 40%, fuel savings up to almost 50%, and potential payback in less than three years. The project uses the Dearman Engine, a high efficiency liquid-air expander that uniquely harvests low grade heat sources and is most effective in urban duty cycles, working with the internal combustion engine as a hybrid. In so doing, more efficient and less transient ICE operation is realised, leading not only to higher efficiency but to potential for improved air quality or simplified aftertreatment. The technology uses readily available materials with low embedded carbon, and operates with commercially available liquid nitrogen which is already produced using off-peak electricity and has great potential for storing “wrong-time” renewables. Bringing together expertise in the Dearman system, industrial gases, IC engines, vehicle systems, legislation and standards and manufacturing, the consortium will advance TRL, MRL and develop an exploitation plan. This will be achieved through an on vehicle demonstration of the system alongside a process of engaging the potential supply, demand and legislative chains. The project creates significant UK advantage in a future urban medium/heavy duty vehicle market of over 3 million units per year.