The Heat is On

A reluctance to part with his money inspired a Dunedin inventor to build his own eco-friendly hot tub. It’s been so successful he’s now testing the water for supplying the world.

Words: Claire Finlayson  Photographs: Sharron Bennett

Stinginess is a good friend to inventiveness. Dunedin physiotherapist Steve August knows this well. His smart new invention the Kiwitub – a portable, chlorine-free, electricity-free hot tub – resulted from a desire to keep his pennies in his pocket. Says Steve: "We wanted something for the crib that would heat up really fast. I was too mean to buy a spa pool and I really didn’t want one anyway because I don’t like the noise and the froth and chlorine makes my skin itch."

The Kiwitub’s evolution dates back 18 years to when Steve and his family were living in a caravan while building a crib in Bannockburn, Central Otago. The only way they could get clean and warm in winter was to light a fire under an old cast-iron bath on the lawn. "It became a real feature," says Steve, "especially because those Central Otago night skies are so amazing. We still used it even when we’d finished the house and had access to showers. But the problem was that you burnt your backside and you could only fit two people in (though we did fit four in once but we had to go sort of sideways and our feet got cold)."

So in an effort to upsize he devised a crude convection-loop system from a wooden tub, a couple of hoses and a big burner constructed from an old copper hot-water cylinder (a bit like a giant Thermette, that water-heating kettle with a fire up its middle invented in 1929 by another clever New Zealander, John Ashley Hart). It worked a treat and stirred hot-tub envy among his friends, so he decided to go commercial. "I thought OK, it’ll take me a year tops. It took me five years of incredibly hard work. Thomas Edison said that genius was one percent inspiration and 99 percent perspiration and that’s exactly what it’s been like."

And so it was that the deceptively simple Kiwitub was born. It’s made of very tough plastic and is heated by burning firewood or gas in a brass and copper burner. You can even plonk your stove-top espresso pot on top of the flue. No motors, no pumps: it’s all about clever physics. Once filled with pure (or salt) water, the tub takes only an hour or two to heat. There’s a complimentary yellow rubber duck on whose underside the word HOT appears if the water temperature goes over 40°C – wife Marilyn’s idea. When you’re done soaking, you just empty the water on to the lawn. Unlike a spa pool it has no running costs and because it’s portable you can pop it on the trailer and take it off to the bach.

The inventor himself: Steve August.

"It’s brute shed technology," says Steve. "I can’t do complicated – I’m a physiotherapist!" He adds that people thought he was a bit of a wally when he was working on the early prototypes. But not now, they don’t: he’s already sold 70 at a cost of $5300 each (plus shipping). A third were bought by engineers who really liked the elegance of the design and one is currently being used by a minister for baptisms. But the biggest potential market is the hospitality industry – weary tourists love the idea of soaking in unsullied water (and therein an absence of previous occupants’ sloughed-off skin). There’s nothing of its type on the international market so Steve has already fielded requests from Sweden, Germany, Australia and the United Kingdom.

Looks as if the Kiwi number-8-wire mythology is alive and well.

Kiwitub Ltd, freephone 0800kiwitub, www.kiwitub.com