Naut cofounder Lindsay Faithfull likes to compare his company’s latest demo boat, Game Changer, to his Tesla.
It certainly has the same push-you-back-in-your-chair acceleration.
Out on the Waitematā, with the Herald on board, Naut head of engineering Collin Davis throttled down the Game Changer to a standstill, then accelerated to close to 40 knots (the equivalent of 75km per hour) in around five seconds - and that was with quite a lot of chop on the harbour.
Naut commissioned the “Ngaru” design Game Changer to show off its third-generation electric propulsion system.
The boat was built by Whangārei’s Harbour Boat Works, and you can order one via Naut, but the start-up’s focus is very much on selling its onboard propulsion system to boat builders to fit into their designs.
The firm also makes an outboard, but the demonstrator is built around its latest onboard system.
“We want people to feel the power and experience the peace that comes with it, and then imagine it in the boat of their choice,” Naut co-founder and chief executive Fiona Bycroft says.
As with an electric car, easing off the throttle and enjoying a bit more of the peace over the power delivers a lot more range.
“At 20 knots you’ll be out on the water for about an hour and a half. Slow down to five knots, you’ve got all day - so say, 100 nautical miles,“ Bycroft says. (That is, the equivalent of around 185km).
With ideal conditions, the new system is rated up to 150 nautical miles on the Ngaru design.
The third-generation in-board propulsion system offers a continuous 225 kilowatts (equivalent to 300 horsepower) with peak power of 405kW (525hp) and is designed for 6m to 24m boats (a small ferry) - all while using a CCS Type 2 charger (the connector that features at most marine charging stations and on most electric cars - a point Bycroft underlined by taking Game Changer, on a trailer, to a ChargeNet EV charging station).
It supports a charging rate close to 100kW, for a recharge time of around an hour via a fast DC charger. With a 22kW or 33kW standard marine (or EV) charger, it will take three to four hours.
It’s all centred on low-cost, industry-standard chargers available today.
“You don’t have to build a big three-storey building,” Bycroft says in a dig at the years-behind-schedule mega-charging structure planned for Queen’s Wharf to support Auckland’s four full-size electric ferries.
Faithfull owns 100% of McKay, a firm founded in Northland in 1936 that has become one of New Zealand’s largest electrical contracting firms with 300 staff (his father bought out the founding McKay family in 1982). He also owns 80.8% of Naut, founded in 2021.
The balance of Naut is owned by Bycroft (10.1%) and Hillfarrance Venture Capital (9.1%). Hillfarrance paid $1.5m for its stake in March 2023.
Hillfarrance has been in the news after its founder, Rob Vickery, left New Zealand last year to return to the UK, leaving his fund unmanned.
Hillfarrance’s main backer, the Crown-owned NZ Growth Capital Partners, took over its day-to-day running. Faithfull says his firm never had any issue with Vickery. He says Naut has no immediate plans or need to raise any further venture capital.
McKay became a big player in the 1960s as it won a major contract with NZ Refining. It got into switchboards for yachts in 2003 and later bought Ward Chandler and Cervina Marine.
In 2018, it won the electrical engineering contract for Ika Rere, the 19m boat that became Wellington’s first electric ferry, and the first electric ferry in the southern hemisphere.
The Ika Rere hasn’t had completely smooth sailing. It was out of service for around 10 months after a breakdown with a driveline. Faithfull says there was no sense of urgency to repair the vessel because the operator had two other boats and was not under capacity pressure.
“If it was wartime, it could have been repaired in a week,” Faithfull says.
The Wellington project helped spur the creation of Naut.
By the end of this year, Naut and McKay between them will have 11 boats in the water powered by their electric propulsion systems, Bycroft says.
Those will include five solar and battery-powered catamarans for Samoa under a United Nations low-carbon emission boat programme plus business in the US, where McKay last year won an electrical systems to integration contract for a programme to replace eight ferries in San Francisco between this year and 2033.
Bycroft is loath to put a price tag on her company’s propulsion system, given it’s highly customised for different designs of boat.
But her rule of thumb is that an electric propulsion system will cost “40 to 70%” more up front than an equivalent combustion system.
“But your ongoing costs are going to drop dramatically. Your maintenance costs almost disappear. Your fuel costs drop down to the price of power,” she says.
She sees a ferry operator or water taxi having a payback period of one to two years.
“It could be seven to eight years for the recreational market,” she adds.
The fiscally constrained Auckland Transport has recently re-embraced the cheaper-up-front diesel option, but Naut and its peers continue to push the merits of electrification – and are earning growing export receipts while they wait for the tide to turn with local government here.
Naut competes with Auckland start-up Vessev and, at the consumer end of the spectrum, ZeroJet. At the bigger end of town, EV Maritime is building the city’s first two fully-electric ferries. But Bycroft says the emerging number of electric contenders will help to build an ecosystem that will lift all boats.
Chris Keall is an Auckland-based member of the Herald’s business team. He joined the Herald in 2018 and is the technology editor and a senior business writer.