NatHERS (Nationwide House Energy Rating Software) is a sophisticated simulation program developed by the CSIRO, the rating result is based on a detailed simulation of the house using hourly weather data. It is used exclusively for ratings in NSW. It is also used in Victoria and other states for projects which exceed the design parameters of FirstRate.
AccuRate is the next version of NatHERS, it is currently undergoing pre release testing; a release date has not been issued at this stage.
FirstRate is a correlation program developed by Sustainable Energy Authority of Victoria (SEAV). The software wasdeveloped by correlating the energy use predictions of NatHERS with building element properties. Using a test set of 55000 ratings in 20 climate zones; FirstRate provides results within 6% of Nathers 99% of the time and within 2% in 88% of tests. FirstRate is used in Victoria, Tasmania, South Australia and Western Australia as the primary rating software with NatHERS being used when the house plans exceed the design parameters of FirstRate. There is a high possibility that FirstRate will be rewritten to become a simulation program over the next 2-3 years.
BERS (Building Energy Rating Scheme) is a computer program used to simulate and analyse the thermal performance of house designs in climates ranging from Alpine to Tropical. It is used primarily for ratings in Queensland Tropical and Sub tropical climate zones.