December 12, 2018
The 2nd Generation NatHERS software integrated a multi-zone ventilation model for natural ventilation, a model for occupant thermal comfort and also the air movement driven by ceiling fans to form an improved model for heating and cooling energy requirement calculations. However, monitored data was not sufficient at the time to conduct a full review of all the assumptions and settings used for the heating and cooling model. Empirical and modelling evidences so far have shown that these occupant behavioural settings require a reality check, to be investigated and updated to maintain NatHERS software as suitable for an energy efficient residential building sector in Australia. An expert group has been established recently with the aim to collaboratively investigate and provide evidence-based recommendations on thermostat and occupant behavioural settings for house energy rating in Australia. Discussions at the first expert group meeting on 22nd June 2018 in Melbourne, identified the following areas for investigations and update:
- Heating and cooling thermostat setting temperatures;
- Triggering temperatures for heating and cooling to be started;
- Cooling effect of air movement including the ceiling fan model;
- Window and window shading device operation rules.
- Zoning of the heating and cooling operation (currently assumed zone to be operated separately);
- Considering that the aim of NatHERS is to provide a ‘measuring tape’ to estimate a home’s potential heating and cooling energy use, the scheme should encourage naturally ventilated designs with non or low heating and cooling energy requirements. Combined or separated metrics for naturally ventilated/mixed mode buildings should be developed.
Members of this expert group include:
- Professor Veronica Soebarto (The University of Adelaide)
- Adjunct Professor Terry Williamson (The University of Adelaide)
- Professor Richard de Dear (The University of Sydney)
- Mr John Shiel (EnviroSustain)
- Dr Richard Aynsley (Building Energetics Pty Ltd)
- Professor Paul Cooper (The University of Wollongong)
- Dr Massimo Fiorentini (The University of Wollongong)
- Professor Wasim Saman (The University of South Australia)
- Dr Stephen Berry (The University of South Australia)
- Mr Lachlan Mudge (The University of South Australia)
- Dr Zhengen Ren (CSIRO)
- Dr Dong Chen (CSIRO)
