What are hydrogen stations and how do they work?

The success of sustainable mobility is based on energy recharging solutions. Today we are going to focus on what hydrogen filling stations are and how they work.

Our dictionary evolves at the speed that we impose on it as a society. This is something that has become especially evident in recent times, where technology, fast and bold by definition, does nothing but generate new terms that we adapt to our daily lives with hardly any time for reflection. This is the case of hydrogen filling stations, whose lexeme – don’t worry, this is not a grammar class – makes it easy for us to deduce that it is something related to hydrogen. Today, in an attempt to provide a moment of reflection and, above all, information, we would like to pause to explain what they are and how they work to provide us with a sustainable transport alternative. So, let’s get to it.

A hydrogen filling station is to a hydrogen vehicle what an electric filling station is to the electric vehicle sector; That is, these are new types of service stations—gas stations in common parlance—that are emerging to facilitate the recharging of new mobility technologies that appear to be taking over from conventional combustion vehicles. Thus, this term emerges as a descriptive alternative to so-called gas stations and, therefore, as a common point when defining all those energy recharging technologies for vehicles that run on green hydrogen. A combustion process whose only waste generated is, remember, water.

If you are interested in knowing how hydrogen is obtained and what the different types are, take a look at our article “What is green hydrogen?”

How do hydrogen stations work?

First of all, we have to keep in mind that these types of technologies are rather scarce today. In fact, many of the plants that currently exist are not just hydrogen filling stations as such, or at least we couldn’t consider them as such, but are green hydrogen production plants—for example, with a photovoltaic installation on the roof of an industrial building—that use an electrolyzer to generate H2 through a complex process. Furthermore, these plants have the option of supplying the fuel produced on-site to their fleet of vehicles. This resource could be seen in logistics companies that have large warehouses and have prepared their vehicles to operate with this 100% renewable fuel. Given that this subsector, despite being perhaps the most widespread, is also the furthest from the revolution that green hydrogen will bring to private domestic transport, today we are going to focus on hydrogen filling stations as such.

These clean service stations are quite similar to the traditional stations we all know, but with their own particularities. Basically, we can say that, in addition to the fuel itself, hydrogen filling stations differ from conventional ones in that they require a sealed seal; what we are recharging into our hydrogen fuel cell is not a liquid like gasoline or diesel, but a gas that is also extremely volatile. Therefore, the fuel is supplied at high pressure quickly and safely with the same process we are used to, but with the small detail that the pump nozzle will be sealed to our tank. However, the filling time will obviously depend on the size of our vehicle’s tank, which in the case of hydrogen is measured in kilos and not liters. If we are talking about a car, the usual time never exceeds five minutes, during which we will be able to refuel the 5 kilograms of H2. On the other hand, a vehicle such as a conventional bus can hold between 30 and 37 kilos of hydrogen, requiring up to 12 minutes to fully recharge the tank.

What parts does a hydrogen refilling station consist of?

We can summarize the main parts of our protagonists in the following:

Storage system or tanks: This is the element designed to store the hydrogen, either in liquid or gaseous form. In a gaseous state, it requires high-pressure storage (between 200 and 700 bars). If it is in liquid form, it must be transformed into gas before recharging our vehicle. In both cases, the hydrogen can reach the hydrogen station through a pipeline or be produced on-site at the facility itself.
Compressor unit or pneumatic compressor: this is the element that equalizes the pressures between the storage tanks and the vehicle. This element is considered essential.
How does a hydrogen filling station work?
Cooler: here we find another key part in the process. The cooler operates the fuel by lowering its temperature to 0 degrees Celsius, due to the expansive characteristics of this material, before being transferred to our car.
Dispenser: we can talk about an element practically identical to the one we find in a gas station with one peculiarity: the refueling hose – actually a nozzle – carries out the process in a sealed situation. In addition, our information display will give us data on the pressure and temperature of the process, thanks to the vehicle-station intercom systems.

How many hydrogen filling stations are there in Spain?

If you are interested in knowing which is the closest green hydrogen refilling point to your home, don’t miss the following website; which shows us all the hydrogen stations that currently exist in Spain – as we have already mentioned, there are very few – and the projects that are under development.

Click on the following image to go to the website and find out more: