Open door for lenders on climate risks at 11m homes

Australia's 11 million residential properties will have their energy efficiency rated by a new tool developed by the national science agency and a data analytics company.

CSIRO and CoreLogic say RapidRate will give buyers and renters more information and help the finance industry better understand the energy efficiency of homes in their mortgage portfolios.

Getting a better grip on energy efficiency could help to manage the risk of higher cost of living in inefficient properties, arm homebuyers with valuable information, and stop banks from refusing to lend.

The nation's houses and apartments are responsible for 11 per cent of total carbon emissions and almost a quarter (23 per cent) of overall electricity use, but well-targeted green loans could support property improvements.

Using the tool, banks and insurers will know how costly a home would be to heat or cool, the carbon footprint of its energy use, and more accurately assess loans and disclose climate commitments.

It may also boost lenders' access to green capital markets, which are bringing new requirements for multi-billion-dollar home mortgage portfolios.

The tool calculates an energy star rating and aligns with the existing Nationwide House Energy Scheme, known as NatHERS, that is used for new dwellings.

NatHERS data from 1.1 million homes was used to train and evaluate the RapidRate model during a 2023 pilot, ensuring consistency between systems.

A thermal rating (0 to 10 stars) assesses design, materials and construction of a home, while a whole of home rating (0-100) predicts energy used from heating and cooling systems, pool or spa pumps, lighting, as well as energy generated from rooftop solar.

"RapidRate can ingest CoreLogic's property data and quickly turn it into meaningful information about the energy efficiency of a home," CSIRO senior experimental scientist Melissa James said on Friday.

"Understanding the energy efficiency of Australian homes is the first step towards making them perform better."

Energy efficient houses can be healthier and more comfortable, cost less to run and result in fewer carbon emissions - and are more attractive for lenders and insurers.

CoreLogic's head of banking and finance solutions Tom Coad said continuous data collection would keep financial institutions at the forefront of the residential energy transition.

Understanding the energy efficiency of the total housing portfolio would mean they could better support customers to reduce individual carbon footprints, he said.