
With more and more Americans spending their time outdoors, often heading out onto backwoods trails, there’s growing interest in off-roaders and, in particular, the off-road recreation vehicles that provide the name for the latest Lexus concept.
The Lexus ROV side-by-side is, in the carmaker’s words, “a unique hydrogen-powered vehicle offering near zero-emissions driving combined with extreme off-road capability.”
There’s been growing interest in keeping things green off-road. Jeep’s Wrangler 4xe plug-in hybrid, for example, can manage hours out on the trails in electric-only mode. And the Lexus ROV is equally green-minded. But instead of using batteries, it relies on hydrogen for power.
“The Lexus ROV is our response to the growing passion for the outdoors and adventurous spirit of luxury consumers,” said Spiros Fotinos, head of Lexus Europe. “As a concept, it fuses our desire to also develop lifestyle-oriented products with our ongoing research into new technologies that contribute to carbon neutrality. As well as delivering a concept that is thrilling to drive, it has near zero emissions thanks to its hydrogen powered engine.”

“Near-zero emissions”
The active term here is “hydrogen-powered engine.” Lexus’ parent Toyota is a big proponent of the lightweight gas as an energy source. But it traditionally relies on fuel-cell technology, as found in the Toyota Mirai where a technology called a “fuel-cell stack” combines hydrogen with oxygen from the air we breathe. That creates a flow of current to operate Mirai’s electric motors. The only exhaust gas is water vapor.
The Lexus ROV feeds hydrogen into a relatively conventional internal combustion engine — in this case, a 1.0-liter package — where it is burned much like gasoline. This approach has been used before by BMW, which tried burning hydrogen in a big 7 Series with an 8-cylinder engine, while Mazda has fed the gas into a rotary engine on several prototypes.

That layout has a number of drawbacks. Among other things, it can result in the production of a small amount of oxides of nitrogen, which is likely why Lexus says the system produces “near-zero emissions.” For now, the automaker isn’t saying much, failing to reveal how many cylinders in the hydrogen engine, nor how much power it produces.
There’s a strong likelihood, however, the engine has the same roots as the one used in a prototype Corolla race car Toyota started testing earlier this year. But that engine did have a turbocharger.
A concept only — at least for now
For now, at least, the Recreational Off-highway Vehicle is just a concept, and there’s no indication whether Lexus has any interest in actually putting it into production. There certainly would be some drawbacks, starting with the lack of a hydrogen refueling network. More likely, the ROV is simply meant to demonstrate the potential for using the gas as a clean(er) alternative to gasoline.

In a Facebook post, a senior Lexus official explained the motivation for the concept vehicle quite simply: asking himself “Why did we build it,” he responded, “because we could.”
Nonetheless, Toyota takes hydrogen technology quite seriously. And it is pursuing a two-pronged approach. It sees vehicles like Mirai building up a retail on-road vehicle market. But it’s also rolling out prototype semi-trucks for use in places like the Ports of Long Beach and Los Angeles. They’re among the dirtiest places in the smoggy L.A. basin, and these fuel-cell rigs could clean things up in a hurry.
Lexus isn’t alone
Hyundai, Honda and General Motors are also pursuing ways to put fuel-cell technology into use in everything from railroad locomotives to aircraft.
This is, incidentally, the second green machine Lexus has rolled out this week. The luxury brand on Thursday teased next year’s formal debut of the RZ crossover that will become its first long-range battery-electric vehicle for the U.S. market.