Passing pedestrians may have wondered what the heck was being lowered into the water.
John Service was trialling his home-made linear turbine in the Orewa Estuary last week.
In conjunction with Engineers Without Borders, he hopes it could be used to provide water and power to places in need around the world.
Mr Service is a former Air New Zealand mechanical engineer but these days is a patent attorney with engineering as a hobby.
He has been working on the turbine project on and off for about 25 years.
Mr Service started when he was in Japan teaching English and tested it there and in Thailand during the 1980s.
It could be used to pump water or as a generator for electricity. And Mr Service says the turbine can be easily made with a hacksaw, tin snips and a drill.
He says it would be useful in places with small villages, such as African countries. Or it could be used on farms anywhere.
The turbine is named after the ‘Tuapeka punt', a means of crossing the Clutha River.
Mr Service says it is the same concept.
The turbine has vanes suspended from cables and chains on a loop which are turned to an angle to the river flow and thus move sideways across the river, pulling the cable or chain which moves in a loop and rotates wheels at each end of the loop.
Engineers Without Borders is an organisation of professionals and students who share a vision to confront global challenges of poverty, sustainable development and social inequity by undertaking initiatives improving the quality of life in communities in the South Pacific region.
- © Fairfax NZ News
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