University of Leicester Medical Building,
Leicester
2015


Integrator :  IBT Controls  -  http://www.ibtcontrols.co.uk

Category :  Commercial



Details


The Centre for Medicine campus will be home to the College of Medicine, Biological Sciences and Psychology departments. Covering 12,836m2 it is UK's largest non-residential project built to the ultra-energy efficient Passivhaus standard and is designed to be up to ten times more energy efficient than a normal building of the same size. The University of Leicester's new Centre for Medicine will replace an existing building on the same site and has been designed to reduce annual energy bills by 80%. Passivhaus buildings provide a high level of occupant comfort while using very little energy for heating. This requires very precise control algorithms to ensure maximum efficiency.

KNX has allowed the building to be controlled to passivhaus standards to a scale never achieved in the UK before. To achieve passivhaus levels of energy efficiency the buildings heating control and control of lighting, solar radiation,c02, natural vent etc all need to be controlled in relation to one another. KNX allows every element of the building control to be integrated and building wide control decisions to be taken and local control decisions to be made that focus on maximum energy efficiency gains. KNX also feeds back all the integrated data to allow plant control decisions to be made.

An exceptional reduction in install complexity and costs was achieved through the use of KNX. Instead of multiple services and cable types into a room wired back to an outstation there was simply the requirement for data, KNX and power into each room. This reduced not only cabling but also reduced other infrastructure costs like basket, tray and conduit.

Full and simple integration into a BACnet BMS front end was also much simpler to achieve using KNX rather than multiple sub systems and protocols that using separate systems across the building would have required.

Programming off site for all the field services allowed a very quick commissioning process to meet the tight program deadlines. Being able to bench test with the BMS provider to prove all operations prior to on site delivery and then being able to program the vast majority of the building off site allows time on site to be spent fault finding rather than programming. 

Lighting Control
Complete building DALI led control with daylight dimming, presence, absence detection, scene control, lecture theatre lighting control into AMX system. Architectural fittings controlled on switch actuator channels. External lighting control. Scheduled lighting control from front end.

Shutter Control
Individual room, internal black out and external solar shading control. Occupancy signal from PIR to set automatic mode based on weather station data of sun position, height, intensity etc. When rooms are unoccupied they act as a complete facade and operate together to reduce impact of solar gain. Integrated with room temperature feedback from KNX room controller to utilise solar gain if room falls below temperature or to reduce solar gain if over temperature. Schedule used to determine building wide operational mode of solar/blind controllers. Building wide alarm for wind, frost, rain to override all for safety

Heating, Ventilation and Air Conditioning
Zoned underfloor heating control via KNX room controller, occupancy, time schedule and Theben Cheops for valve control. Fan coil heating and cooling based on occupancy, room temperature, building mode on time schedule. Radiator valve control based on occupancy, room temperature, building mode, room controller set point C02 quality control utilising occupancy PPM, fan coil and natural vent control from VAV controller VAV control provides fresh air based on C02 levels, occupancy, room temperature Solar control of heating from blind controller and weather station data.

Alarm Systems
Link to fire and security alarm to engage lighting to 100% output in event of activation. Monitoring of critical alarms in comms rooms via volt free contact and temperature sensors to specific alarm conditions

Audio/Video
Interface to theatre AMX systems for lighting and scene control including activation of blinds.


Energy Management
KNX forms the entire field level control and data provision for the building wide BEMS. All control data on occupancy, lighting levels, internal room temperature, C02 levels, solar levels, external lighting levels, wind speed, rain and frost alarms, blind position, ventilation actuator position and airflow, slab temperatures and humidity are all integrated with one another and with the BEMS to influence plant control decisions, building wide KNX control decisions and local room level KNX control decision.


Visualisation
Entire building alarming, data display, monitoring functions are displayed on one completely integrated building BEMS head End. Control decisions and monitoring of the entire system can be taken from this visualisation, as can alarm handling. A bespoke integration page developed between KNX/BACnet to indicate for each object the value received on the KNX side and the BACnet side to reduce complications of fault detection and rectification between integrated systems without requirement to have engineering knowledge of both protocols.


Interfaces
Interface of complete system to BMS provides for plant room control and building wide control from one point. Interface with AMX system and interface to fire and security alarm.

Remote Surveillance/Control
Remote access to entire building available to the ETS platform or to Front End. KNX apps provided to lecture theatre controllers.