The estimated average gap between calculated and actual energy performance of the European building stock is 25% for energy performance and 1.5% for comfort performance (as scored by building occupants). Comprehensive research has shown that poorly commissioned and operated building management systems are often responsible for this gap, generally caused by the lack of appropriate and coherent Quality Management Systems (QMS) for building performance.
To tackle these challenges, the project QUANTUM developed and demonstrated pragmatic services and appropriate tools supporting QM for building performance in the design, construction, commissioning and operation phases.
The presented case implemented the tools developed by QUANTUM project and allow to assess the potential savings thanks to the application of an effective QMS.
The new constructed building, the Karl Landsteiner University, fulfils a dual function as an office and an educational institution containing auditoriums, class-/seminar rooms and laboratories of various sizes next to the administrative office areas. It is equipped with a reversible ground source heat pump providing warm and cold water for room heating and cooling, a compression chiller as a backup system for cooling as well as several air handling units and a photovoltaic system on the buildings’ roof. The useful energy is provided by space heating / cooling systems such as thermo-activated building components and floor heating as well as via the air ventilation units. The operation of all systems is supported by a building management system. The building is owned by the federal state of Lower Austria and operated by an external facility management company.
The quality management service started immediately after the building was handed over from the constructor to the building owner. The main objective was to identify deficiencies relating to the BMS and energy efficiency improvement potentials from the very beginning, in order to meet the energy performance targets and to secure a good indoor environment. It is therefore an addition to the already implemented energy monitoring infrastructure.
The service comprised four performance tests carried out within the first year of operation including the setup of an online platform which enables the facility management team to constantly supervise the operation of the systems. Additionally, a user survey was conducted. The results of the individual performance tests were reported to the client. Any anomalies and deficiencies found have been passed on to the BMS contractor. As a consequence, these faults could be corrected within the warranty period.
The performance tests were based on the execution planning and the parameters set during the commissioning by the BMS installer. The operation data was handed over regularly once a week by the BMS. The online-dashboard was updated automatically. In agreement with the Facilities Management team, performance checks for a defined period were conducted. Identified faults were evaluated based on the actual operation data and instructions issued in order to fix deficiencies.
The QMS has been implemented in the heating, cooling and ventilation system, with a more effective operation of the ground source heat pump, the compression chiller, the central air handling unit as well as in the decentralised ones.
Thanks to the QMS it was possible to lead:
- Heating consumption from 337000 kWh/year to 315300 (- 6%)
- Cooling consumption from 154000 kWh/year to 133500 kWh/year (-13%)
- Electricity consumption from 112000 to 93200 kWh/year (-16%)
- With a total energy saving of 10%.
This lead to a total energy saving of 10% and also to a reduction of the operation cost calculated at approximately 10,000 Euros per year. Further potential savings arise by:
- Less stress for the ventilation system since the fluctuation of the duct pressure could be reduced
- Replacement of not operating sensors
- Repositioning of unsuitable placed sensors
- Recalibration of energy meters
- Less stress for the heat pump due to a reduction of the switch-on / switch-off processes