This paper focuses on the influence of inlet air temperature and relative humidity on the performance of a proton exchange membrane fuel cell (FC) stack with maximum power of 175 W. To control the inlet air temperature, a cooling system was designed and integrated with the fuel cell stack. It was experimentally proven that the lower temperature results in better fuel cell performance. This dependence was found to be non-linear in the range of 15–25 °C. To take into account air humidity and analyze its effects on FC efficiency, an air humidifier was installed at the air inlet. Experiments showed that the increased relative humidity positively affected FC efficiency. Computational fluid dynamics (CFD) simulation of the reactant flow inside the FC stack was conducted, helping to analyze thermal regime, velocity distribution, and migration of hydrogen ions through the membrane on the cathode side. The temperature on the cathode side exceeded operational limits already at 120 W power load. CFD simulation results support the need for an additional cooling system for experimental setup.

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Newcastle Science Central is introduced; a 24 acre city centre site being developed as an exemplar sustainable urban environment encompassing Smart Grid technologies throughout. A real time energy management algorithm is proposed to maximise the power availability of the site's flexible electrical assets; all of which have different operating characteristics. Each asset is considered in an equivalent form similar to energy storage, allowing it to be compared on a like-for-like basis through a virtual state of charge. The new Enhanced Frequency Response service offered by National Grid is used as a case study to demonstrate that through intelligent energy management, the site operated as a virtual power plant, can deliver greater value than the sum of the constituent assets operating individually to the same overall control signal.

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