Existing lack of control
The building, constructed in 1977, held a large proportion of single occupancy offices and small lecture rooms. The main problem with the building was a lack of flexibility with the existing building management system. It was not possible to heat less than 200 rooms on a single heating circuit, as there was no automatic control at radiator level. If only one room was occupied, half of the building would have to be heated.
The result was that the approximate cost of heating the buildings over a 4 year period was £44,563.
A system was devised to save energy by providing real-time information about the use of the building’s heating system and room-by-room temperature control to both the building management team and the room occupants. Unoccupied rooms would now be turned off automatically or by management staff.
The specific products used were TRVs (to control the radiators), window sensors (to detect open windows and turn down the heating), and a mounted display tablet to offer users knowledge of the room temperature and control of the heating. Administration staff could remotely be informed, by alerts on the web App or by email, if windows were open for a couple of days, long term empty rooms, abnormally high or low temperatures, and maintenance issues such as low batteries.
A detailed, independent thermal modelling study indicated that savings of between 7% and 29% were achievable for office assuming that the windows were always closed, and savings of between 42% and 46% in rooms where windows were frequently left open (as the system would automatically switch off the heating).
It was also predicted from survey results that greater user control and improved user perception would decrease tendency to utilise expensive supplementary electric heaters.
The study at University of Warwick remains on-going; however results so far are promising. The less efficient spaces have shown a reduction in energy consumption of close to 20% before optimisation of the system. With on-going optimisation, LightwaveRF firmly believes much greater savings can be achieved and results are eagerly awaited.