Making your home more energy efficient will obviously lower your energy bills. But making even minor adjustments to your home’s efficiency can also have an important impact on your health and healthcare costs.
The results of a groundbreaking three-year study – undertaken by researchers at the University of Technology Sydney (UTS) and Sustainability Victoria – drive home the benefits of retrofitting older houses to make them more energy efficient.
As part of the study, more than 1000 homes in Melbourne’s western suburbs and the Goulburn Valley in north-east Victoria were given free ‘energy retrofits’ consisting of improved insulation, draught sealing and reverse cycle heating.
The homes were split into two groups of about 500, with one group receiving the upgrades before winter and the second group after winter.
Study participants had an average age of 75 and all were on a low income and had chronic health issues.
Average daily winter temperatures in the households that received the upgrades increased by between 0.33 and 0.47 degrees Celsius in the mornings – usually the coldest time of day in the house due to heating being switched off at night.
This translated to a reduction of time spent exposed to cold indoor temperatures (defined by the World Health Organization as being less than 18°C) by 43 minutes per day.
Overall electricity use was reduced by 0.9kWh/day and gas use by 7.1kWh/day, which translated into $69.70 in savings per household during the winter months.
The research also revealed significant improvements in physical and mental health in the group that received the upgrades before winter.
Residents reported feeling warmer and noticed less condensation, which leads to damp and mould.
“We also saw improvements around important aspects of quality of life, such as reduced anxiety and increased feelings of safety and comfort,” says Professor Rosalie Viney, co-author of the study.
“Overall, participating households with energy interventions saved $887 per person on healthcare costs over the winter period.”
Gas bills over winter dropped by $85 (also meaning lower greenhouse gas emissions), and they used fewer medical services than the post-winter group, resulting in an $887 saving to the healthcare system. The study found that the upgrades would save nearly $5000 over 10 years.
They also found that combined health and energy savings would mean the cost of the intitial upgrades would be recouped within a few years.
“Combined with the energy saving and compared with the average $2800 install cost [of the upgrades], the intervention would be cost-saving within three years,” the study says.
“For every $1 participants saved in energy costs, they saved $10 in health.”
Kerryn Wilmot, head of the Institute for Sustainable futures at UTS, says she hopes the study will be used to strengthen the case for improved building standards in Australia.
“There’s an absolutely critical need for Australia to improve the quality of its existing homes,” she says.
“Nearly half of Australian homes are estimated to have an energy rating of below 2 stars, compared with the 7 stars mandated for new homes. It’s crucial that we start overhauling substandard housing stock in Australia – especially for vulnerable members of the community.”
How cold does your home get in winter? What upgrades could make it more energy efficient? Share your tips in the comments section below.