The district heating system served by the CHP also incorporates Danfoss FlatStation heat interface units to ensure instant hot water to the clusters and studios and provide separation between the primary and secondary sides of the heating system.
St Michael’s Hall was developed by Iliad Group and the student accommodation is operated by Sanctuary Management Services. The hall comprises 264 bed spaces arranged in clusters of 5 and 6 bed apartments, with shared kitchen and dining facilities, together with studio accommodation.
Iliad Group has a strong commitment to sustainability so energy efficiency and low carbon emissions were key elements in the design of the building and this is reflected in the services designed by Manchester-based consulting engineers Futureserv.
“We worked closely with architects Formroom to achieve a thermally efficient building envelope so that space heating requirements are minimised,” explained Futureserv’s Craig Cleary. “We also specified energy efficient lighting and ventilation, so that the dominant energy demand in the building is for domestic hot water. We considered a number of low carbon heating options and CHP was the most practical and cost-effective solution and had excellent payback potential,” he added.
The SAV 20kWe/40kWth CHP unit provides heat for both domestic hot water and space heating in the winter, as well as electrical power that is used on site. The LoadTracker modulates in response to variations in electrical demand to avoid selling surplus electricity to the grid at unfavourable rates.
The 7 Series FlatStations have been installed as an interface between the primary district heating system and the heating and DHW circuits. The temperature and pressure controls within the FlatStations guarantee optimal comfort for the end-users providing instantaneous hot water at stable temperatures at the taps. This arrangement also keeps energy bills as low as possible during the heating season, as only the limited primary flow required for the highly efficient plate heat exchangers is allowed through the primary side of the FlatStations.
The integral temperature and pressure controls also permit very low primary return temperatures from the FlatStations, which are crucial for the efficiency of the system as a whole, and the central plant and CHP specifically.
Danfoss FlatStations are wall-mounted and delivered to site preassembled reducing installation costs. As DHW is produced instantaneously on demand standing losses and space requirements were minimised compared to traditional cylinder solutions. The design and construction of SAV FlatStations means that virtually no maintenance is required after installation.