Ross and Chris Greenwood will spend the next three years living on and sailing their 12.3m ketch Sula.
During their voyage, they will sail from New Zealand to French Polynesia then Chile before heading back the same way to Australia.
The couple have lived in Wanaka since they moved to New Zealand from the United Kingdom 15 years ago.
Mr Greenwood is a project manager and Mrs Greenwood a social studies teacher at Cromwell College.
As part of the trip they will carry out conservation and educational work on the issue of plastic pollution in the oceans.
A trawl attached to the boat would be used to gather data from the ocean, which would then be sent to scientists in New Zealand, Chile and the United Kingdom, Mr Greenwood said.
It had taken about two and a-half years to plan for the trip and about the same amount of time to save enough money, he said.
About $30,000 had been invested in the boat so Mr Greenwood was sure it would last the trip.
There would be times where they would sail for more than 25 days without reaching land, which could be quite daunting, he said.
"I’m pretty experienced and Chris has experience and it’s always tough when it’s only two but we know what we’re doing."
Other than not having a shower or hot water, the boat was "pretty good" to live on and there would be times where they were docked for a few weeks at a time.
"We won’t be living in luxury but we won’t be living rough either."
As much food and water as possible would be loaded on to the boat before they left New Zealand and Mr Greenwood hoped the food would last until they arrived in Chile late next year.
"We will also be fishing and getting seafood where we can, so hopefully we’ve planned properly."
Leaving their two daughters, Erin and Ellie, behind in New Zealand would be one of the most difficult parts of the trip, he said.
Being apart for such a long period of time would be difficult but the girls would visit them when they were sailing around French Polynesia.
Once the couple were back in Australia, they would go back to work and save up for their next trip.
They will keep supporters updated through their website www.sulasailing.com.
