On track for success with hydrogen – scalable supply security for alternative drives

Dr. Martin Schneider is in an enviable position: He is playing an active role in shaping the future of the transportation sector. As the Business Development Manager at Siemens Energy for mobility infrastructure solutions he is certain that a transition to hydrogen and innovative infrastructure solutions for fueling trains with hydrogen is essential in order to keep things rolling. As he sees it, this all needs to happen in the next 30 years. And that isn’t long at all when you consider the development of renewable energy, which was still an insignificant niche product 30 years ago.

Mr. Schneider, is hydrogen the oil of the future?

Let’s put it this way: Whatever runs on gasoline today will be battery-powered tomorrow. Whatever uses diesel fuel today will be driven by hydrogen tomorrow. Of course, that’s just a general rule of thumb, but as we see it, all forms of mobility that move heavy loads over long distances – we’re talking trucks and ships as well as aircraft and rail vehicles – will be emission-free, running on either electricity or hydrogen.

 

What makes hydrogen so important for the rail sector in Germany, particularly compared with electrification?

It might help to take a broader view and look at the question from a different angle: Of course rail electrification is desirable and makes sense ecologically. But it’s not economical everywhere, because the distance is too long and passenger numbers/capacity utilization are too low. There are countless reasons. The fact is, though, that almost 40 percent of Germany’s rail network is still not electrified. And that is not likely to change in the foreseeable future. Although much is being done right now to lower the cost of electrification, it still costs around 1 to 2 million euros to electrify one kilometer of rail – and it’s just not worth it for some 30 percent of the lines. 

These numbers from Germany apply similarly across Europe. If we want to replace the existing diesel engines on these lines, too, and operate with zero emissions, we need battery- or fuel-cell-powered trains. Although batteries are definitely attractive for shorter hauls, hydrogen-based solutions have an advantage on routes that entail steep grades or long distances because they have enough power reserves.

For hydrogen, we are facing a similar task as we did with renewables 20 or 30 years ago.
Dr. Martin Schneider, Business Development Manager at Siemens Energy for mobility infrastructure solutions

Is sector coupling a key reason for H2 becoming the fuel of the future?

Absolutely. Hydrogen is an excellent medium for storing energy, and we urgently need that. Electricity always has to be generated when it’s meant to be used, which makes for a complicated supply situation, especially when we look at international interconnected grids and the volatility of renewable power generation. The more renewables are used, the more capacity for energy storage is needed, to ensure a consistently steady supply of electricity regardless of fluctuations in its generation. Batteries simply can’t be scaled to that extent. And that’s where hydrogen comes in. It’s an incredibly flexible, emission-free energy storage medium that can be distributed and converted back into electricity at a later time. And best of all: It can be carried on board the trains.

What infrastructure does hydrogen need in order to be successful?

We expect demand for hydrogen to increase not only in the mobility sector but across industry in general – and ultimately everywhere that electricity needs to be stored. We can also use this infrastructure to at least partly solve the problem of how to make unpredictable renewables like wind and solar a reliable energy source on a European scale. For that, we need a European hydrogen pipeline system comparable to the one currently in place for natural gas. With it we could connect Europe’s industrial centers to those locations that have the greatest capacity for generating renewable energy. Electrolyzers like our SILYZER 300 will play a key role: Multiple units can be combined into large, industrial-scale plants capable of supplying this future infrastructure – wherever renewable energy is consistently in great supply – or used individually as smaller, decentralized systems where the hydrogen is needed, for instance at individual fueling stations or factories. 

How will hydrogen be distributed until then?

Right now, there are essentially two commercial technologies available for hydrogen transport: direct local pipelines between generator, consumer and tank storage, either as compressed gaseous hydrogen (up to 1,000 kg H2 in high-pressure vessels) or cryogenic liquid hydrogen (up to 4,000 kg H2 at –253 °C in specially insulated tanks). In addition, work is currently underway to render the existing natural gas infrastructure usable for hydrogen as well. To date, transport modalities have largely been determined by customers’ individual needs – in the case of mobility customers, based on daily needs. If these are less than 1,000 kg, gaseous hydrogen can be supplied via tube trailer. For higher needs, cryogenic hydrogen or on-site generation by means of electrolysis, which considerably simplifies logistics, especially for large train refueling stations, makes more sense.

 

What role does cost efficiency play?

As always, costs are a crucial point. Of course, prices will depend on many factors, not the least of which will be demand. Technologically speaking, we must do everything in our power to reduce costs as much as possible. If we look at the factors in detail, we see that electricity prices and the combination of availability, efficiency, and plant service life are the main ones for on-site electrolysis. We can’t do much about electricity prices, but we can influence the latter three factors. And in an effort to really explore all the possibilities, we are using a digital twin to simulate and optimize the system’s operation under a wide range of scenarios. We’ve gone so far as to incorporate daily electricity prices, hydrogen demand, and other individual factors into our simulations so as to find the best possible plant schedules for our customers.

Viewed on a larger scale, however, the cost-effectiveness of green hydrogen depends largely on the policy framework: For instance, financing conditions and the tax treatment of green hydrogen compared to blue or grey hydrogen. And how the market for green hydrogen can be put at an advantage, through visionary policy decisions like carbon pricing, emissions trading, and binding emissions reduction targets or the recast of the EU’s Renewable Energy Directive (REDII) in order to ultimately achieve the necessary economies of scale. 

What can we expect in terms of electrolysis development?

We mustn’t forget: In the big picture, fuel cells and PEM electrolysis are still very new technologies – with correspondingly vast potential for development. More specifically, right now we are driving development of new variants of our largest electrolysis system, the SILYZER 300. There is broad potential for optimization. And besides working to make it easier for our customers to utilize economies of scale, we’re also taking a close look at the overall system’s energy efficiency. A key here is the system’s output pressure, since the hydrogen generated often is used on site with a certain pressure, or must be transported. For that, it is usually compressed, regardless of whether it will be shipped in pressure vessels or distributed through a pipeline. Every bar of additional output pressure in the electrolysis process ultimately reduces the amount of energy needed for compression and improves efficiency. Besides pressure we are seeking to further optimize our technology’s productivity, efficiency, and sustainability with various approaches.

Do you see hydrogen as the primary fuel for non-electrified rail lines in the future?

I think we should reframe the question. It’s not so much about how much hydrogen will be used as a fuel in the future but rather how fast it will be used. The energy transition is a great example: Key political decisions and a conscious commitment to decarbonizing the energy economy have enabled us to advance specialized technologies like wind and solar power, which were initially far too expensive, and lead to the global breakthrough in renewable energy production. With subsidies like those under Germany’s Renewable Energy Act and economies of scale among manufacturers, we were able to achieve grid parity. And now these technologies generate electricity more cost effectively than conventional power plants. For hydrogen, we are facing a similar task as we did with renewables 20 or 30 years ago.

What does that mean in concrete terms?

Specifically, we’re talking today about cost-effectively producing green hydrogen – that is, carbon-free generation of hydrogen. Inexpensive electricity from renewables is widely available. Now we have to establish the corresponding hydrogen infrastructure – in other words, create the technological conditions for producing and transporting green hydrogen cost-effectively. Unfortunately, we are still in the early days of that development – and once again it will all depend on the right decisions being made: Policymakers have to declare a clear commitment, the markets have to use intelligent tools, and finally, industry has to develop the technologies needed for a hydrogen-powered future. That isn’t going to happen overnight, but I am confident that we can write another success story on a timeline similar to that of renewables.