Inventor and saxophone player Peter Davey has come up with a device that he claims boils water in no time.
He calls it the "sonic boiler" because he claims it uses the power of sound. How the heater actually works has confounded experts.
The device looks oddly like a bent desk lamp, with a metallic ball at the end instead of a lightbulb. When plugged into the power supply, and the ball is lowered into water, it boils the liquid within seconds -- even as little as a tablespoonful.
"Everybody boils twice the amount of water they need so I decided I would find a way to boil water and make steam more economically," said Davey, a former Spitfire pilot.
"This boils exactly what you want to drink."
Davey, who lives in a tumbledown two-storey historic homestead called Locksley in Dallington, has been using the boiler to make hot drinks for 30 years.
He said he first came up with the concept 50 years ago and it took him half of those years to figure out how to make the device.
"The principle is beautiful. I have cashed in on a natural phenomenon and it's all about music," he said.
"If I hadn't been playing the saxophone, I probably wouldn't have come up with the idea."
Davey noticed as he played the saxophone at home that everything resonated at a different frequency.
"The glasses will tinkle on one note. Knives and forks in the drawer will tinkle on another note and I realised that everything has its point of vibration," he said. "In the same way, a component in the ball is tuned to a certain frequency."
Davey said it took years of trial and error to get the device to where it is now. He has made a number of prototypes using the same principle, including a steamer.
Friends dropping by over the years have urged Davey to make them a sonic boiler and that got him thinking commercially.
Davey, who turns 92 today, is now looking for a manufacturer who will buy the technology and make the devices for the mass market.
"Nowadays, with the economy of water and electricity, I think it could be even more important than when I conceived the idea," he said. "They could sell a million of the things in China."
Davey estimated boilers could be made as cheaply as $9 each. He could imagine cafes using them as a gimmick to make express tea and coffee.
"I cannot wait to explain the principle to somebody who wants to take it on," he said.
The Press invited a retired Canterbury University engineer, Professor Arthur Williamson, to look at the boiler and he was stumped.
He watched Davey boil various quantities of water, took notes of the energy used and temperatures reached. He left scratching his head.
"I don't know enough about sound to know whether you can transfer that amount of energy via soundwaves. I doubt it," said Williamson.
He did remember an alternative kettle years ago that had two perforated metal plates inside. The power ran between the plates, through the water. "The resistance through the water provided the load. I wonder if it isn't working like that? Without taking it to bits, you can't tell."
The kettle was specially designed to prevent people getting a shock from touching the boiling water.
Williamson's verdict of the sonic boiler? "It is an interesting gimmick, irrespective of how it works. I would probably buy one as a gimmick. I think more homework needs to be done."
Also queuing up for a boiler, after first seeing one in the 1960s, is Stu Buchanan, leader of the Garden City Big Band and a friend of Davey.
"It's rather spectacular. I don't know why it has never taken off as a utensil for people. I think it's a class act," said Buchanan.
Davey was born in Hamilton in 1916. During World War 2 he flew Spitfires for the 602 City of Glasgow Squadron of the Royal Auxiliary Air Force. The squadron operated along the south coast of England, escorting bombers to Holland and Belgium, doing convoy patrols and fighter sweeps into France.
After the war's end he married and had two children. He bought Locksley in 1964. Davey shares the top storey of the homestead with his 55-year-old son, also called Peter, and a grey tabby cat called Santa. The ground floor is let to lodgers who help pay the bills.