HEV waste heat recovery system

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Sunamp designs, develops and manufactures phase change material (PCM) based thermal energy storage devices that can store heat and coolth for many days. We call these devices heat batteries. They have been successfully deployed on residential and commercial housing schemes for more than five years and are now being used to address thermal management challenges on vehicles. Battery electric (BEV) and hybrid electric vehicle (HEV - in electric mode) range is comprised in cold conditions, up to 50% in temperatures down to -30ºC. Typical best in class HEVs (cars and vans) only achieve between 29-35 miles (NEDC), winter will significantly impact that range.This application looks at the challenge of maintaining HEV cabin heating when the engine is off. Doing so will extend range but also reduce emissions in this mode, as the IC engine is off, and the cabin heating is only powered by the HV battery, quickly depleting the limited stored energy. When this happens and the IC engine has cooled off below the stop start threshold, the IC engine restarts, giving an emissions spike as it slowly warms up. The emissions are less the quicker the engine gets back to optimal temperature, and this was proven in two NVN funded projects completed in 2017 and 2019\. Both these projects showed that we could significantly reduce hybrid electric double decker bus cold start emissions (around 50%) and maintain engine temperature and cabin heating throughout the TfL low emission bus test cycle. Waste heat was captured from the engine coolant, in this feasibility study we will investigate the improvement by capturing high grade heat from the engine exhaust gas stream.Sunamp has teamed up with IAV, a leading automotive engineering consultancy, to stabilise the high temperature PCM needed for this application; simulate the impact of adding heat battery sub system into the vehicle cabin heating system; designing a concept that could feature in a future R&D programmes and develop the business model to best maximise the market opportunity.