BMW iX5 Hydrogen

FIRST DRIVE SUV shows off the potential of hydrogen fuel-cell power

- Tristan Shale-Hester

HYDROGEN fuel-cell technology seems through into the world of passenger cars for a while. But aside from a few forays, manufacturers haven't exactly leapt at the chance to put the tech into series production, as they have with full EVs.

However, BMW has bucked this trend and will build a run (albeit a limited one, of just 100 units) of iX5 Hydrogen models, which will be going into service this spring, partly as a rolling laboratory to see if hydrogen could be viable in the future.

The basic recipe packages two carbon fibre-reinforced plastic hydrogen tanks within the standard X5's chunky body, which hold almost 6kg of hydrogen at a pressure of 700 bar. These feed a hydrogen fuel cell mounted under the bonnet, which is rated to produce 168bhp - although this is not the car's actual power output.

Instead, through a chemical reaction, the fuel cell converts the hydrogen into electricity, which is stored in a power battery. This can be charged by either the fuel cell or kinetic energy recovery when the car is slowing down, and the electricity from this battery supplies a fifth-generation eDrive motor on the rear axle, which has a total power output of 396bhp. The only emissions from the fuel cell are water vapour and heat, with the latter captured to warm the car's interior.

On the move, the iX5 Hydrogen behaves similarly to its smaller iX3 EV sibling, as well as the iX SUV - no surprise given there are some carryover parts. The iX5 moves off silently and swiftly thanks to a strong surge of torque. Due to the limited-run car not being on sale to the public, BMW hasn't revealed its full specifications, but the firm has said it's lighter than an equivalent battery-electric model. Instead, it weighs a similar amount to a plug-in hybrid X5 xDrive45e, placing it at around 2,500kg. As such, the BMW is swift enough; 0-62mph is completed in less than six seconds.