London Underground is tasked with increasing the sustainability of its’ major infrasructure projects, including both the construction, operation and maintenance. Continued London population and employment growth and associated increase in passenger demand necessitates continued major station capacity upgrade projects. Holborn station is LU’s highest priority station capacity upgrade project and will be delivered by the mid 2020s. The project will also facilitate station platform cooling and a replacement, expanded basement level traction sub-station to support the planned Central line upgrade increased train frequency over the next 10-15 years. Combined these two project elements will provide waste heat that would otherwise be exhausted to atmsophere, creating an unsustainable outcome for London. The Trigeneration feasibility study therefore aims to test whether this waste heat could be harnessed to supply local third parties and to test whether there is a more holistic, decentralised means of generating cooling and power as part of the station capacity project.y