Technology and innovation are enabling more options of heating and cooling buildings with previously space age ideas becoming more economical. Developers can achieve big savings by engaging in new methods which save in both building costs and on-going running costs.
One of these options is utilising underground piping to transfer heat exchange from ground temperatures to fluids within the piping. This system can control all elements in the building’s Heating Ventilation & Air Conditioning (HVAC).
HVAC represents the largest estimated energy consuming active design element within a Residential Tower development. The initial HVAC capacity range can be estimated using the ‘CAMEL’ energy modelling software tool, through information such as the internal floor areas, and insulation and glazing values for the new facility. An example is shown in the following table:
|Optimum HVAC Capacity Range|
|Total||3000 kW||3500 kW|
Based on review of the table and the base building area, it can be recommended that a centralised, hybrid chilled water / ground source heat exchange system be installed, as shown in the above figure, by leveraging the surrounding soil for refrigerant heat dissipation.
In the above scenario, by utilising this proposed hybrid HVAC strategy, the roof area allocation for the HVAC plant would be reduced by at least 30% whilst releasing approximately $800,000 ex-GST from the build cost through an Engineer Procure Construct and Maintain (EPCM) contract. It would also reduce ongoing HVAC operating costs for common areas and individual lots by at least 50% whilst providing “free” swimming pool water heating via waste heat recovery. Installation of an integrated HVAC control system is also recommended as part of the proposed ground source heat pump system in order to provide further savings in HVAC energy consumption of up to 10%.