The sunlight hits John L Hayes' Mayfield house just right in the winter.
On cold days he and his wife sit in their winter room warmed partially by the sun thanks to well-placed vegetation.
Renovating houses to be more sustainable is one of many ways the couple has attempted to promote sustainable living over a number of years.
"My wife and I have been fairly environmentally aware for a long time [since] we lived in Sydney," Mr Hayes said.
Since retiring to Newcastle in 2004, Mr Hayes has been looking for ways to encourage others to live more sustainably and learn how Australia can transition to renewable energy.
He has also been involved with multiple climate and environmental groups in that time, particularly Climate Action Newcastle since the mid-2000s, and more recently, Beyond Zero Emissions.
"[Beyond Zero Emissions] have been represented here in the Hunter for a number of years, and that is increasing," Mr Hayes said.
"We see an opportunity here in Newcastle to be able to use non-carbon based energy.
"The resources we're using at the moment are finite.
"There's a desperate need to transfer to using renewable energy where you can."
Mr Hayes said there was an increasing amount of research looking at the possibility of transferring to renewable energy to make electricity.
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He has spent many years encouraging others to consider how they can live more sustainably.
"We have to conserve what we've got and we have to make things better than they have been in the past," he said.
"There are opportunities right across the spectrum to take the pressure off the planet.
"Australia is in a terrific position to be able to do that."
Mr Hayes' involvement in community groups involves varying activities, depending on what is happening - from helping with submissions to campaigning.
"It's not all negative," he said.
"We assist with information by organising seminars and forums.
"In some cases, I've been one of the principal organisers, and in others I've helped the organisers."
Mr Hayes said there were a couple of things people could do to live more sustainably.
"You can start to educate yourself, you can inquire about joining a group or a society that are interested in those issues," he said.
"If people are interested, they can find a group of like-minded people that is up and running.
"There are plenty of groups around and there are a number of very interesting websites."
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