FILL’ER UP WITH H2: TWO TYPES OF FUELING STATIONS FOR FUEL CELL VEHICLE FLEETS

You can’t talk about fuel cell vehicles without talking about fuel. After all, it is a main contributor to the total cost of ownership of a vehicle. In the hydrogen industry it has been a chicken and egg discussion for decades – will the availability of affordable hydrogen spur on fuel cell vehicle development? Or will the demand from fuel cell vehicles drive the development of hydrogen infrastructure and commodity market? Now as the market matures, it’s a bit of both.

While battery electric vehicles get a lot of press in driving a zero-emissions future, fuel cell vehicles are proving to be a strong part of the mix required to electrify transportation at a mass scale worldwide. This is especially true in markets that require long-range and demanding duty cycles with minimum downtime, like trains, buses and trucks. At just a fraction of a battery’s weight, hydrogen is capable of storing much more energy.

But how does a fleet get the hydrogen to keep its vehicles in operation?
There are generally two options to secure hydrogen fuel supply: hydrogen can be delivered, or it can be produced onsite. Let’s explore these scenarios.

Gaseous or liquid delivery
This option requires the hydrogen supply to be trucked in, often compressed and/or cooled when in storage at site and through delivery. If a readily available hydrogen production source is economically close, this option can offer lower upfront development costs in comparison to the other options.

A station such as this can use either “grey” or “green” hydrogen based on availability. Currently almost all the approximately 70 million tons of hydrogen produced today is considered grey hydrogen because it is produced from natural gas. This process emits approximately 10 tonnes of CO2 for each tonne of hydrogen produced. In this regard a station using a gaseous or liquid delivery model has access to a larger market of potential hydrogen, but it may not be as clean as onsite generation options.

Where infrastructure exists, hydrogen can also be delivered via pipeline. This is the lowest cost way to transport hydrogen over long distances. While there is currently only one retail hydrogen station in the US that is supplied hydrogen through a pipeline, as the need for hydrogen fuel grows, a wider network of pipelines could be developed. In the short term, delivery via trucks or onsite generation will likely be the primary methods to supply hydrogen.

Onsite hydrogen generation through electrolysis
Alternatively, a fleet can produce hydrogen onsite using an electrolyzer sized and scalable to meet fleet needs. This ensures ample supply is available to keep fleets operational.

When electrolyzers are powered from renewable power sources such as wind, solar or hydroelectric, the hydrogen is green. It has the lowest possible well-to-wheel carbon emissions compared to other fuels, as well as battery and hybrid counterpart systems. When powered from a public electricity grid, hydrogen generated with an electrolyzer takes on the environmental attributes of the local energy mix. If the energy mix feeding the electrical grid has low carbon emissions associated with it, (such as wind, solar, nuclear) so does the hydrogen produced using that power.

A single 1MW electrolyzer system can generate over 400 kg of H2 daily at 99.98 percent purity. This is enough to fuel 12 freight trucks up to 225 miles/day each, and these systems have already been scaled successfully to over 20MW configurations.

Cummins made a bold entry into the hydrogen generation market in September 2019 with the acquisition of Hydrogenics, a global hydrogen fuel cells and electrolyzer technology manufacturer. Through this acquisition Cummins has already delivered electrolyzers for more than 60 hydrogen fueling stations across the globe and expects the world’s initial attention will be on replacing grey hydrogen with green hydrogen to help reach our climate change targets.

Accessible hydrogen makes fuel cell transport a realistic option. Over time, both the price of renewable power and the price of electrolyzers are set to decline—projected at over a 60-percent reduction in the coming decade—leading to widely available green hydrogen at a lower cost.