The on site sustainable energy source (groundwater borehole infrastructure system) installed during the previous phase of the development will be extended to provide heating and cooling within the new building. The previous phase of the development utilized the groundwater system in conjunction with a water cooled VRF (variable refrigerant volume) simultaneous heating and cooling system to provide a highly energy efficient solution to the buildings heating and cooling needs whilst satisfying the requirement to utilise an on site energy source to provide a minimum of 10% of the buildings energy usage.
The Client has set the design team a target of further improving the energy efficiency of the Phase III development over and above what is already a highly efficient solution.
In conjunction with engineering the façade and the incorporation of solar shading, the design is being based around a chilled beam installation to provide cooling within the building in conjunction with water cooled heat pump technology to provide the heating needs; both systems will be served from the ground water borehole system.
During the summer months, the groundwater which is abstracted at a constant temperature of 11-12oC will be circulated through the chilled beam installation (via heat exchanger and secondary pipework loop) to provide cooling within the building without the addition of any mechanical cooling plant. This will provide in effect ‘free cooling’ as required throughout the year with a significant reduction in energy usage and the associated carbon production and running costs.
During the winter months heat will be extracted from the groundwater via the heat pump system which has a high co-efficient of performance (typically 5 to 1) to provide heat within the building.
The combination of the above, will result in the building achieving the energy efficiency target set by the Client and being one of the most energy efficient buildings if not the most energy efficient commercial office building in the North West of England.
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