Recently, we published an article on the Lider portal titled ‘Just let it be consumed: We have no hydrogen cars, but we are building ten hydrogen filling stations‘, in which we stated that not a single hydrogen vehicle is registered in Croatia, yet the Minister of Sustainable Development Damir Habijan recently announced the construction of as many as ten hydrogen filling stations, for which around 23 million euros will be allocated.
This article was responded to by Prof. Emeritus Dr. Frano Barbir, President of the Croatian Hydrogen Association, who believes that the article contains inaccuracies and adds that critics should have spoken up when the Croatian hydrogen strategy was in public discussion.
– Now that the Ministry is trying to implement the strategy by building hydrogen filling stations, there are critics who do not understand the problem and who think that battery electric vehicles are the only solution for the decarbonization of transport, or, I would not be surprised, think that we do not even need decarbonization – writes Barbir in his response, and subsequently sends corrections to the inaccurate or half-true statements from the text.
The article states that the application of hydrogen in transport is inefficient and continues that ‘for this purpose, it is necessary to build a continental hydrogen distribution network at very high pressures of 700 bar.’
Barbir says that this is not true and that ‘pressures of 700 bar are only in the tanks of cars. In buses, trucks, and trains, 350 bar tanks are used. It is not necessary to build a continental network for hydrogen distribution at 700 bar. In fact, it is not even necessary to build a hydrogen distribution network because hydrogen can be produced at the point of consumption – at the filling station itself.’
Furthermore, the text states ‘compared to battery electric vehicles, the efficiency of hydrogen vehicles is three to four times lower.’ Barbir says that this is true.
– The efficiency of hydrogen vehicles is three to four times lower than the efficiency of battery electric vehicles. But efficiency is by no means the only criterion. If we had used only that criterion, it would never have occurred to us to produce electricity from fossil fuels, nor would we have used internal combustion engines to power cars. Hydrogen has several advantages over batteries, such as energy density, separation of power from energy, and refueling time – adds Barbir.
He continues, saying that the hydrogen system in a car (which includes hydrogen, hydrogen tank, and fuel cell with all accompanying devices) has three to four times greater energy density (in kWh/kg) than the best batteries.
– This means that the hydrogen system is three to four times lighter than the battery system. In the hydrogen system for powering cars, power is separated from energy – the power of the system is the power of the fuel cell, and the amount of stored energy is proportional to the amount of stored hydrogen. In the battery system, both power and energy are in the batteries. Therefore, if the system needs more power or more energy, it is necessary to add more batteries, while in hydrogen propulsion, a larger fuel cell is needed for more power, and for more energy (thus for vehicle range), a larger hydrogen tank is needed. For this reason, hydrogen makes more sense in heavier vehicles with greater range, such as buses or trucks. Hydrogen also makes more sense for passenger trains on non-electrified lines longer than 100 km, where fewer than ten trains operate daily – says Barbir.
Technology close to commercialization
One of the most significant advantages of hydrogen electric vehicles is the refueling time of the tank. The tank typically contains 5 kilograms of hydrogen, which, with a consumption of 1 kg/100 km, gives a range of 500 km (N.B. one kg of hydrogen contains the same amount as 3.7 liters of gasoline). Such a tank is filled in about the same time as today’s gasoline or diesel tank, i.e., in about five minutes. Batteries need to be charged significantly longer, depending on the power of the charger, it can take from about 15 minutes to more than an hour. If all cars in some future were battery-powered, we would need several times more charging stations than we have today, or the queues at charging stations would be several times longer than today.
Superfast chargers would require either enormous peak power (and an appropriately adapted distribution network) or huge amounts of additional batteries. Besides efficiency, energy density, and charging time, it is necessary to compare other characteristics such as safety, operation in extreme conditions, performance loss over time/durability, availability of materials/recyclability, and most importantly – cost. None of these criteria gives such an advantage to battery electric vehicles that would justify calling hydrogen vehicles ‘technological and economic crime’ – says Barbir.
The text also states that ‘hydrogen technology is in development and is not even close to commercialization’, which Barbir refutes.
– Most technologies for the production, storage, and use of hydrogen are either commercial or close to commercialization (TRL 9 or higher). Only the use of hydrogen in ships and aircraft is still in development (TRL<7) – says Barbir.
The interlocutor in the text also states ‘that the entire concept of the green hydrogen economy is based on a misguided assumption that there will be very large surpluses of produced energy from wind or solar energy available at some point in the future.’
– If the goal is to completely decarbonize the energy sector, it means abandoning the burning of fossil fuels. According to current knowledge, the only system in the future that could replace fossil fuels is a system based on renewable energy sources. Due to their nature, wind and sun are variable sources, and therefore there will indeed be surpluses of produced electrical energy from wind in such a system. This is not a misguided assumption but a fact. In such a system, it will be necessary to solve the problem of storing large amounts of energy for longer periods. Batteries are not that – they are good for storing relatively small power (on the order of MW) and for storing energy for shorter periods (on the order of several days). Again, according to current knowledge, hydrogen can be used for seasonal storage of large amounts of energy. In that case, hydrogen as a fuel for transport will be available – says Barbir.
Furthermore, the interlocutor claims that ‘materials in contact with hydrogen lose properties essential for the function of pipelines and become brittle.’
– Not all materials in contact with hydrogen become brittle. By choosing materials or lining the inside of pipes with appropriate coatings, this problem is easily solved – says Barbir.
Also, in response to the claim that ‘hydrogen is explosive in a wide mixing ratio with air and requires very little energy for ignition or explosion’, Barbir says that this is ‘a typical half-truth that I have heard many times before, and which is presented either by malicious critics or those who do not understand safety aspects.
– It is true that hydrogen is flammable in a wide mixing ratio with air (specifically from four percent to 75 percent), but achieving a hydrogen concentration in the air of four percent is harder than achieving the concentration of any other gas (methane or propane/butane) at the lower flammability limit because hydrogen is almost 13 times lighter than air, and in open space or in an enclosed space with any, even natural ventilation, it is practically impossible to achieve a hydrogen concentration of four percent, except in the immediate vicinity of a hydrogen leak (about 30 centimeters above the leak point). It is also true that the minimum required ignition energy of hydrogen is lower than that of other gaseous fuels, but in safety considerations, the ignition energy at the lower flammability limit is crucial, and that value is similar for both hydrogen and natural gas – says Barbir.
EU has adopted a strategy
The text also states that ‘the idea that hydrogen will replace natural gas in households, in such a way that some old lady would cook coffee on a hydrogen stove is truly technologically incredible.’
However, Barbir says that our grandmothers actually once cooked coffee on a hydrogen stove.
– Namely, in the period between the two wars, the so-called town gas was used in cities, mainly for lighting, which was nothing more than a mixture of hydrogen and carbon monoxide – he says, adding that he agrees that using hydrogen instead of natural gas in households does not make much sense today because all the energy needs of a modern household can be fully met with clean and safe electricity. He also agrees that mixing hydrogen into natural gas is not a good idea, even in some transitional period – writes Barbir.
In conclusion, he adds that the European Union has adopted a hydrogen strategy, and then Croatia did as well.
– Hundreds of companies and research organizations in Europe are working on hydrogen technologies, united in HydrogenEurope and HydrogenEurope Research. Investments in hydrogen technologies are being made through public-private partnerships, the so-called Clean Hydrogen Joint Undertaking (by the way, I am the official representative of the Republic of Croatia in this partnership, and the Croatian Hydrogen Association is a member of HydrogenEurope). According to the conclusion from your article, these are all organized criminal organizations engaged in economic and technological crime and embezzlement of money from both taxpayers and private individuals – says Professor Barbir, adding:
The point is that the decarbonization of transport cannot be achieved solely with batteries, especially for heavier vehicles and longer ranges. The fact is that charging batteries takes an order of magnitude longer than filling today’s cars with diesel or gasoline, which means that in the future we will need an order of magnitude more charging places, or we will have to reconcile ourselves with long queues at charging stations. Fast charging with high power requires new infrastructure (just like hydrogen) and many more batteries. Studies have shown that such infrastructure would be at least as expensive as hydrogen, if not more expensive.
Also, hydrogen (from the surpluses of electrical energy that will be available in any case) will be needed for the decarbonization of those sectors/industries that cannot be electrified. The main problem is that for now, we really do not need hydrogen because we do not have surpluses of electrical energy, and serious decarbonization of both transport (especially heavier transport) and industry has not even begun. But that does not mean that we should not prepare for the introduction of hydrogen. After all, that is why we have a strategy (both Croatia and the EU). Another problem is that people who do not understand the energy transition (or do not want to understand for some personal reasons/interests) and do not see the bigger picture write about the transition – concludes Barbir.
