Benchmark tool
The benchmark tool (AccuRate Home) is used by the NatHERS Administrator to measure the accuracy of software tools seeking NatHERS accreditation. This ensures outputs are consistent across all accredited tools.
The benchmark tool is developed and managed by the Commonwealth Scientific and Industrial Research Organisation (CSIRO) and provides an assessment and rating of a home’s appliances in alignment with the NCC 2022 energy efficiency performance requirements.
- It includes the key regulatory appliance modules included in NCC 2022 (heating and cooling appliances, hot water systems, swimming pool and spa pumps, lighting, onsite solar photovoltaic (PV) and battery systems) as well as allowances for non-regulated loads (such as plug-in appliances and cooking loads). This allows NatHERS tools to be used for NCC 2022 as well as provide valuable information to users about energy use across the whole home.
- Within each appliance module, the tool provides a larger range of appliance types than offered under the NCC 2022 elemental pathway.
- It calculates the annual energy use of a home (by fuel type), solar PV generation and battery storage, electricity imports and exports.
- It provides a breakdown of energy use by module so that users can see what is having the largest impact on energy use.
- It provides a Whole of Home rating based on the energy value of the home (the metric used for NCC 2022).
A commercial version of the NCC 2022 compliant AccuRate is available from Energy Inspection.
Watch the Whole of Home benchmark tool demonstration video.
Accredited Software
All software used to produce NatHERS energy ratings certificates must be accredited in accordance with the NatHERS Software Accreditation Protocol.
Software tools accredited for use under NatHERS for demonstrating compliance to NCC 2022 are based on the CSIRO calculation engine, Chenath (v3.22 or 3.23). These are listed at Software updates.
Key modelling inputs
To ensure calculations are accurate, representative of Australian conditions and are comparable across different types of housing, the Software Accreditation Protocol requires all accredited software tools to meet strict performance standards.
Some of these performance standards include:
CSIRO’s Chenath calculation engine
The Chenath engine has been developed by the CSIRO. It uses decades of climate data and average user behaviour, among other factors, to predict annual totals of hourly heating and cooling energy requirements for residential dwellings. More information on the Chenath engine can be found in the Chenath repository.
The Chenath engine was validated in 2004 against the international standard ANSI/ASHRAE 140-2001.
For more information read the Validation of the AccuRate Simulation Engine Using BESTEST.
Including new materials in NatHERS software tools
The Technical Advisory Committee (TAC) considers whether new materials and products should be included in the databases of the NatHERS accredited software tools. As with software updates, the TAC’s recommendations are provided to the NatHERS Steering Committee for approval before the new materials can be included.
WERSLink Library
Integration of the new WERSLink window libraries into NatHERS software continues to progress. Refer to Software updates for information on software tools that now include the WERSLink libraries. The new WERSLink libraries have been highly anticipated, however there will be a transition period whilst users become accustomed to the new feature.
For WERSLink technical information and guidance please refer to the NatHERS Assessor Handbook and Technical Notes and the software's technical support manuals. NatHERS will also use the NatHERS FAQ’s or the NatHERS Newsletters to keep assessors updated.
Learn more
- For further information on Whole of Home changes please refer to the Frequently Asked Questions page.
- View the new certificate for the expanded Whole of Home changes.