World-first hybrid drive caravan revealed

World-first hybrid drive technology that allows a caravan to push a car up a hill, and capture energy from regenerative braking on the way down, has been unveiled at the Victorian Caravan Supershow.

Developed by Campbellfield, Victoria-based technology start-up, OzXCorp, the hybrid caravan system uses a 16kW/508Nm hub motor to drive the wheels, in conjunction with sensors to deliver “real-time stability control, torque vectoring, ABS and brake-blending”, said OzXCorp Co-Founder, Andrew Huett.

“Hybrid drive technology is not new but the adaption of these principles to caravans is a unique challenge by virtue of the caravan being an autonomous vehicle,” Huett said.

“Whenever you tow with a caravan it’s a burden. So the goal with this was to remove that burden and get the joy back into caravanning," he explained.

"We’re not trying to push you across the Nullarbor; it’s about all those stop-starts, and about fuel efficiency where it will push harder up a hill and ride the brakes down hill, recovering the energy and maintaining speed.”

Huett said the hub motors at around 13kg, are lighter than traditional 12in drum brakes. As well as smoother towing, Huett said the patented hybrid system incorporates reverse parking technology, to help back into tight spots and assist hitching up, at speeds up to 2km/h.

Various auto-style off-road drive modes, including Sand, Mud and Hill Assist, are also available for off-road conditions to help push the trailer along and avoid getting stuck, while torque vectoring (braking one wheel while driving the other) will help when cornering.

OzXCorp is also working on an autonomous ‘break-away’ system, where the trailer would steer itself while avoiding traffic before finding a safe place to park, if separated from the tow vehicle. Weight management 'sensors' and trip odometers are also part of the package.

“It is both impractical commercially and weight wise to make the trailer fully electric driven, that is, fitted with more than 80kW/h of battery," Huett explained. "However, most of the benefits of an electric drive system can be realised by making a hybrid drive system that utilises a smarter energy management system."

Also part of OzXCorp's bespoke hybrid system is a big 16kW/hr powerpack, that works in conjunction with a 5kW inverter and up to 2000W thin-film photovoltaic roof solar panels, to deliver domestic-style power delivery when caravanning.

Weighing around 115kg, the high-capacity lithium-ion powerpack including battery management system is mounted under the floor within the chassis rails, alongside similar-sized water tanks.

“It’s a 52 volt sub-system inside, so it’s a big step up in going truly off-grid,” he said. “You can walk inside your caravan and have a full domestic experience for a week-end, including running an induction cooktop, washing machine, kettle, and convection microwave simultaneously…

"The Truma under-bed air-conditioner (in our display van) alone will run for four days non-stop, without any topping up from the solar panels!”

OzXCorp plans to bring the cutting-edge caravan technology to market in 2020 by partnering with existing RV manufacturers like Victoria’s Retreat Caravans, which built the ‘gas-free’, full-composite 19ft 9in caravan on display at the Supershow.

The hybrid technology will be offered on both single and dual axle caravans, with real-world testing of full-size tandem axle caravans to take place around Australia later this year.

While retail pricing will be set by the RV manufacturers that offer the OzXCorp technology, Huett said the full turn-key system including hybrid motors and 16kW/h powerpack could add around $20,000 to the overall cost of the caravan.

Huett, who has an electronic engineering background and extensive experience in the automotive and IT fields, said the aim is to produce a ‘smart’ caravan that can deliver the goods both on- and off-the-grid.

“In more advanced versions, this would actually recover energy and sell it back to the grid," he said. "There are a lot of possibilities, but it’s no longer a caravan. It’s much more than that…”