They now provide their own, milk, sausages, bread, vegetables, meat and beer.
Mr Vinbrux said although they had always tried to live in a sustainable fashion in Germany, increasing bureaucratic regulations and an expanding population had started to turn their home village into a residential suburb of nearby Aachen.
Mrs Vinbrux said Oamaru was the perfect place to achieve a fully sustainable lifestyle.
''We loved the area, so we stayed. Now we have pigs, bees, cows and a large vegetable garden. We don't buy any vegetables now from the supermarket.
''We spend about $80 a week on groceries for six people.''
Mr Vinbrux added that their sustainable way of life in Oamaru had been taken to a far greater scale than they had ever been able to achieve in Germany, and it also had the advantage of allowing them to eat traditional food from their home country, without having to pay high prices for imported goods.
''Good handmade cheese you just can't afford, and the same is true of handcrafted German beer, and I like beer too much to pay $8 a bottle for it.''
His home-made beer costs about $1 a litre to brew.
However, sustainable living was not all about price. It was more about achieving a better quality of life, he said.
''Some people think they can buy a lifestyle block, and both work 40 hours a week jobs and get away every weekend and still make a profit from their vegetable garden. Unfortunately that's just not realistic. The simple life is not simple.''
The couple also breed Icelandic horses to provide an income, which Mrs Vinbrux said ''mostly'' covered their mortgage.
''We don't make much money, but we eat like kings every day.''
For the past three years the couple have been passing on their 30 years worth of knowledge to fellow locals at the Transition Oamaru sustainable skills summer school, and once again they will be mentoring people at this year's summer school, which starts tomorrow and runs to January 27.
The couple will tutor a range of ''hands-on'' sustainable living courses, including backyard poultry, making sauerkraut, making bread and brewing beer.
Anyone with a 1000sq m (quarter-acre) section could achieve a sustainable way of life with just a good vegetable garden if they put in the hard yards, Mrs Vinbrux said.
''There is a lot of physical labour needed; you certainly don't need to pay to go to the fitness centre to keep fit.''
