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.