Imagine seeing a whirlwind rising more than a kilometre into the air.

You’re not scared, though, any more than you would be at seeing a windmill. You know the slim vortex is going to be stable. Far from causing any damage, it’s generating power from waste heat at an industrial plant.

This is the vision of Vortex Power Systems, a Waipapa Taumata Rau, University of Auckland spin-out company that sees itself as part of a zero-carbon future. It may sound like a radical idea but it’s one with solid science behind it.

In 2014, Neil Hawkes was at an airfield in Matamata, servicing the engine of the gyrocopter he flies as a hobby, when he saw a dust devil form. It lasted an unusually long time, about 15 minutes, and it got him thinking about how much power was in it.

“It lodged in my head as an idea and when I got bored of messing around with gyrocopters, I thought, ‘Maybe I’ll chase this idea,’” says Hawkes.

The experienced engineer and entrepreneur went to talk to Professor Richard Flay about the idea and suggested getting a master’s student to do more research into the idea.

“Richard suggested I do it myself. So I did a research masters degree and then was offered a PhD scholarship,” says Hawkes.

As a student, Hawkes participated in Velocity, the entrepreneurship development programme run by the Business School’s Centre for Innovation and Entrepreneurship, to help him turn the idea into a company.

“Fairly early in the process, I had to decide whether to keep my research patentable or publish, so I went to see [Director of Commercialisation] Stephen Flint at UniServices," says Hawkes. “He said UniServices would fund the early stages of the patent, which meant I could go ahead and publish academically without affecting the patent application.”

The University of Auckland Inventors’ Fund and deep-tech fund Pacific Channel provided initial funds to prove the concept and Vortex Power Systems was born. Hawkes, who is now almost finished his PhD, is Chief Technical Officer. Flay is Chief Scientific Officer, while Perzaan Mehta, who has a background in both engineering and business, came on as Chief Executive Officer in 2020.

To develop the technology, Hawkes started off researching how whirlwinds form in nature. These phenomena are smaller and thinner than tornadoes and are driven by ground-level conditions, unlike tornadoes, which are driven by the storms above them.

Whirlwinds pull hot air or steam up their cores, much like chimneys. They thus cool the hot air/steam while generating kinetic energy in the form of swirling air.

Many large-scale industrial processes use steam to convert heat into power. The steam is then condensed into water and returned to the boiler. However, these processes are only about 30 percent efficient and produce a lot of waste heat.

“It’s an opportunity for us but it’s a practical and ecological problem for industry,” says Hawkes. “They have to get rid of that hot water, but how? If they dump it in the river, they’ll kill fish. So they use cooling towers with massive fans to cool the water but that’s expensive and a waste of energy.”

For most engineering purposes, water at 40 to 70 degrees is too cool to be useful. However, in atmospheric terms, even 40 degrees is hot. Vortex’s technology can use industrial wastewater in that temperature range to saturate air, which then rises. When a swirling air pattern is also present, a vortex forms. 

Game-changing technology isn’t built overnight. After having filed its first patent in 2016, Vortex Power Systems set up as a company in 2017 so it could raise money to build a testing unit. The lab-scale rig proved the concept in 2019 and further experiments in 2020 showed the technology would be cost-effective at a larger scale.

The company completed a seed round of funding in 2021 and raised $2 million to operationalise the company, including building out the team, bringing on a board and designing a full-scale demonstration station.

The team has now mostly secured consents and a site and is working on contracting workers to build the station.

Though the idea of a whirlwind extending kilometres into the air may sound frightening, the engineers say the dangers are low.

Because the heat driving Vortex’s technology stays in one place, so would the artificial whirlwind. If there were an intense side wind, the vortex simply wouldn’t form.

“To give you an analogy, if you were to pour oil on a table and set it alight, you could move the flame around by blowing on it because the source of fuel is diffuse. That’s what a natural whirlwind is like,” says Hawkes. “Our vortex is more like a flame on a candle. If you blow on a candle flame, you can’t detach the flame from the candle, but if you blow hard enough, you’ll blow it out.”

Nonetheless, the engineers believe a full-scale vortex would withstand most wind conditions.

According to the company’s calculations, 50 percent of the world’s power consumption is lost as waste heat. Vortex doesn’t expect to be able to capture anywhere near all of that. Nonetheless, if widely implemented, its technology could make a significant dent in greenhouse gas emissions.

“Notionally, 7.5 to 10 percent of any industrial process or power plant emissions could be cut by using our technology,” says Mehta. “That’s a couple of hundred billion dollars of electricity and it would be zero-carbon.”

The technology would also save money for the industrial plants that implement it, says Mehta.

“Our design is relatively simple so it wouldn’t cost a lot to build. Plants would start saving money right away because they wouldn’t have to run cooling towers and the electricity they generate would go back to them. If they were a power plant, they could still provide the same amount of power with less fuel use, so they’d save on that as well as on carbon pricing. It’s a win for everybody.”