Around 500 fork-lift trucks at the BMW Group’s US plant in Spartanburg run on hydrogen. These additions are part of the American plant’s ambitious sustainability strategy. Because hydrogen propulsion makes even more sense here than electric power.
Filling up at the BMW Group plant in Spartanburg is certainly different. Here, unlike at a regular service station, if you position the nozzle incorrectly, you hear a loud “pffft”, and that was it. Nothing happens. Nor should it: Because the refuelling mechanism is not activated until the pump is securely locked in place.
There is a very good reason for this: The hydrogen gas being pumped into the tanks of the almost 500 forklift trucks and tuggers used in Spartanburg is under the same pressure you would find at more than 3,500 metres under water – around 350 bars. A precise fit is therefore crucial for safe refuelling.
Battery-powered forklift trucks became standard in the industry some time ago. The benefits of clean power and zero emissions for indoor operation are undeniable. Now, the BMW Group plant in South Carolina is showing that forklift trucks do not have to be operated by battery or even still, run on diesel to maintain performance capabilities. It is proving that a hydrogen-powered truck is more environmentally-friendly as its battery-operated “twin”. The hydrogen arrives at the Spartanburg plant as a liquid. It’s stored in a 15,000 gallon tank near the energy centre. The liquid hydrogen runs through a vaporizer where it is converted into a gas. It’s this hydrogen gas that is pumped into the forklifts and tuggers all over the plant site.
From the outside, the two forklift trucks are hard to tell apart – but the chemical processes taking place inside them are fundamentally different. While batteries break down elements into their component parts, the new forklifts convert hydrogen and oxygen into electricity, heat and water. This process, also known as "cold combustion", initially posed technical challenges for engineers. "The resulting heat is discharged through a fan that has to be specially mounted on the forklifts and tuggers”, explains Cleve Beaufort, Energy Manager for the Americas. "We also had to equip the factory halls with special gas sensors and smoke detectors so that the hydrogen containers would not create a new safety risk."
The efforts have paid off. First, of course, are the environmental benefits, since batteries are no longer needed. In addition, the risk of acid leakage from a defective battery is eliminated altogether, and disposing old batteries in the landfill no longer takes place. But there is also a great savings of time. Changing the depleted lead-acid batteries for a newly-charged battery took 20 minutes of time. Old batteries had to be disposed of in landfills. With hydrogen power, you can refuel the unit in about three minutes. That’s valuable time in a high-paced production environment.Hydrogen is also largely produced through “eco-friendly” methods; it is manufactured at the most sustainable source within supplier Linde’s network.
And the Spartanburg plant is also benefitting directly in another way: “The switch to hydrogen has also freed up a lot of valuable space in the production area,” said Beaufort. “We now use that space for assembly production and logistics.” In the meantime, the hydrogen fork-lift trucks have become so reliable that this positive experience will soon be passed on to other BMW-Group plants.