Tom Osborn and Heather Robertson are not trying to change the world, but they are trying to make a difference, and it is helping their pocket and the planet at the same time.
Mr Osborn (26) was a carpenter in Britain.
He now works as a strategy analyst for the water and waste department at the Dunedin City Council.
His partner, Ms Robertson (25), is completing a master's degree in science communication at the University of Otago.
They have grand plans for building their own sustainable, green home in the next few years, but at the moment they rent and try to make cuts wherever they can.
The big changes started when their van broke down three months ago.
They decided that rather than replacing or repairing it, they would get rid of it, and use pedal power to get to work.
Since then, they have saved on petrol as well as the costs of maintaining, registering and warranting a vehicle, and kept up their fitness at the same time.
If the weather is particularly bad, they will catch the bus.
Mr Osborn said he could not remember the cost of petrol and did not need to keep a watching brief on whether the price was going up or down.
They save money on food by buying at the Otago Farmer's Market and by foraging for other food, such as cockles.
They also make their own bread and pasta and, where they can, they do not buy packaged food, which in turn saves on waste.
They need to empty their rubbish bin only once every two months.
They achieve this by reusing any packaging that they do buy (such as bread bags) and by composting food scraps.
They have started a vegetable patch and have plans for a chicken coop.
Mr Osborn said they were not extreme about things.
They found alternatives when and if they could.
"I would never give up showering but I cut down the time I spend in there," he said.
Their biggest saving has been cutting down on power.
They do small things, such as boiling the jug for washing dishes rather than having to empty the hot water tank; they turn off any electrical appliances which are on stand-by; they wash their clothes on a cold wash and they use energy-efficient bulbs and turn them on only when necessary.
They have a ripple relay system for their hot water tank which means it is turned off 16 hours a day.
They use a heat pump, as Ms Robertson has asthma and does not want to exacerbate it by being cold, but they do not leave it on all day.
Their power bill is as little as $50 a month.
The couple say anyone can achieve household savings - it is just a matter of being willing to change.
Sustainable living
1.Cut back power use.
Think about hot water you are using as this is a large chunk of power supply, and every time hot water is used, the tank fills up with cold water, meaning power is used to heat it again.
2. Make and grow your own food.
Make bread and pasta and grow fruit and vegetables, if you can.
3. Use a vehicle sparingly. Before they got rid of their van, they only used it to go for surfing holidays, otherwise they cycle everywhere they need to go.
4. Cut down on waste, and therefore the cost of getting rid of it, by using less packaging.
