NatHERS 2022 Climate Files - Summary

The climate files used to calculate star ratings for the Nationwide House Energy Rating Scheme (NatHERS) will be updated with more recent and more accurate weather data. The new files, associated with 69 Climate Zones across Australia, will now include data from 1990 to the end of 2015 instead of 1970 to 2005.  

The new climate files have the potential to impact NatHERS ratings inconsistently across Australia. This may affect calculations for the predicted energy load of some homes. To minimise these impacts, new NatHERS star bands will be implemented at the same time.  

Developing NatHERS climate files

The new climate files are based on comprehensive weather monitoring records spanning 25 years. Each of the 69 Climate Zones has its own Reference Meteorological Year (RMY) that underpins the NatHERS assessments for this zone. Every RMY is comprised of hourly measurements of wind speed and direction, pressure, temperature, moisture content and data on solar radiation.  

The 69 NatHERS Climate Zone locations that the climate data applies to remain unchanged and can be viewed on the NatHERS interactive Climate Zone Map.

Other updates include:

  • A new climate file has been added for Christmas Island to offer a better representation of the climate in tropical island locations  
  • Nationally consistent data on estimates of global (G) and direct solar radiation (R) based on Bureau of Meteorology satellite monitoring
  • Minor corrections to altitudes, latitudes and longitudes of location sites and algorithms to remove erroneous values and to fill data gaps
  • Updates on primary weather station closures and alignment with Automatic Weather Stations (AWS)
  • The removal of extended periods of inaccurate data
  • Corrections for erroneous wind data generated by faulty equipment.

To find out more information on the methodology and details of the new climate files read NIWA Climate file 2016 final report.