An electrified residential thermal system using heat pumps and thermal storage

Chief Investigators

Dr Ahmad Mojiri  (RMIT)

Purpose of project

Thermal applications account for 40-60% of the energy use in the residential sector. There are currently no commercial, electrical, cost-effective systems that can supply hot water and space conditioning from one central unit. Instead, households have to install separate systems, with high upfront costs and constrained space capacity in increasingly dense residential blocks. 

The widespread operation of individual hot water and heating and cooling heat pumps used on demand also contributes to morning and evening peak grid load, necessitating demand-side management that compromises indoor thermal comfort. This sub-optimal approach results in high cost and space requirements. 

Impact of project

This project will develop an Australian-made 3-in-1 heat pump system with hot and cold thermal storage, providing space heating/cooling and hot water from a central unit. Compared to existing alternatives, it is estimated to have 30% lower capital cost, 66% lower lifecycle cost, requires up to 70% less refrigerant, needs less space and only one point of access to outside air, which is valuable in the increasingly dense built environment. It will suit retrofit and new builds. 

It simplifies the electrification process for households, allowing them to reduce running costs and emissions. When combined with solar PV, it is estimated that this system will be able to slash grid electricity load and emissions of a home by 60-75% based on RMIT modelling.  

Project partners – industry and research

RMIT (Lead), ActronAir, C4Net