Among other renewables, hydrogen energy

Institute for Nuclear Sciences VINČA, the National Institute of Republic of Serbia, is located in Belgrade’s suburban settlement Vinča, which also conceals a remarkable archaeological site that names the Neolithic Vinča culture. The Vinča site is located above the union of rivers Bolečica and Danube, and if a sightseer visiting the archeological site decides to visit the Danube's right bank, they can taste a fantastic fish stew in the restaurant overlooking the river confluence. VINČA Institute is nearby the Vinča archeological site and cluster of riverbank restaurants, thus they are perfect for lunchtime during warm and sunny days.

The last days of October are usually warm and pleasant in Serbia, so we decided to take one of our colleagues out for lunch, to marvel at the autumn colors of aerial view on Vinča and Danube, to talk about science, upcoming projects, all in all, our jobs.

Our colleague, Igor Milanović , is an assistant research professor at the VINČA Institute and a member of CONVINCE – Center of Excellence for Hydrogen & Renewable Energy. Igor Milanović acquired Ph.D. from the Faculty of physical chemistry in 2015 and dedicated his career to scientific research.


Igor's academic info

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Quantum Gap: Your scientific activities are focused on the advance of clean and renewable energy. In particular, you are a participant in the national Proof Of Concept (PoC) research and development project, where you study the functionality of innovative materials used for hydrogen storage and hydride fuel cells. What is the expected short-term project outcome? 

Igor Milanović : We have currently an active PoC project aiming to make experimental hydrogen (H2) storage tank in tandem with commercial fuel cells. The main idea is to obtain an experimental setup for a controlled and safe absorption/desorption cycling process. Desorbed hydrogen will be used for electricity production using the fuel cells. 

Quantum Gap: Which project particularities will contribute to the long-term renewable energy strategy of the Republic of Serbia?

Igor Milanović : The Working Group for a circular economy within the Ministry of Environmental Protection of the Republic of Serbia has developed A Road Map for Circular Economy in Serbia, an important document that sets guidelines for the transition towards a circular economy. Serbia is the first country in the region to prepare such a document. This document includes the use of hydrogen as an energy vector of the future. 

If we are talking about the impact of project particularities on long-term strategy, there are a few important points. PoC solutions in hydrogen energy storage can encourage transformation from fossil fuels to renewable energy strategy. Also, direct implementation of cheap solutions can be used in the near future, i.e. for substitution of environmentally more invasive techniques for energy storage and production.

Quantum Gap: What are the advantages Serbia offers to the European hydrogen energy research universe? 

Igor Milanović : If there are any, we should enable their wider exposure in the media. To be recognized as a forward-looking, innovative community it is imperative to start building the first hydrogen refueling stations in Serbia. We don’t have time to wait if we want to be a part of the European hydrogen station’s map. 

Furthermore, everything powered by a battery can also be powered by the electric current produced from fuel cells. This is why the first application of hydrogen energy in Serbia may be presented, for example, in form of the remote transmitters for base stations of mobile networks - their “batteries” can be powered by hydrogen. Especially after the inclusion of 5G base stations, given that for 5G to be operational, a massive infrastructure of about 50 base stations per square kilometer is needed.

study dealing with issues and advantages of renewable’s integration into the electrical grid of French islands, with the focus on Corsican island, is published in the Renewable Energy journal in 2019. It is sufficient to say that it encourages the further development of at least sporadic renewable energy systems. Additional info is available here


Quantum Gap: If you had the opportunity to choose your research path one more time, knowing all you know now, would you choose to work in the field of hydrogen energy?

Igor Milanović : Hydrogen energy has its place in the near future; it will complement Li-ion batteries, or some new types of batteries, as the source of energy. Mainly in remote areas, such as islands, which are far from the usual energy sources and power plants; a perfect example being the island of Corsica.

Electricity from, for example, solar panels can be used to perform water electrolysis, which is a common technique for hydrogen production. It is performed in electrochemical reactors called electrolyzers, with only reaction products being hydrogen and oxygen. Oxygen is easily captured and stored, while hydrogen is stored in the form of hydrides, a chemical compound within steel reservoirs. Heating up the reservoirs, hydrogen gas is desorbed and used in fuel cells together with oxygen. As a result, electricity and drinkable water are produced.

Quantum Gap: Decarbonization efforts – the solar-powered electrolysis would be a fantastic solution for hydrogen production in terms of minimizing carbon dioxide pollution, but is it recommended from the economical aspect? Also, is it feasible with state-of-the-art technology?

Igor Milanović : Clean hydrogen gas production is still exotic. Electricity gained from renewables like solar is still too expensive to be used for further production of hydrogen. It is due to become affordable, but for now, over 90% of hydrogen is produced by the exploitation of fossil fuels in refineries, by steam reforming of natural gas. 

On the other hand, laws and regulations world-wide advocating for clean energy are becoming stricter and vocal. At the moment, EU members are determined to produce 32% of energy from renewable power sources, up to the year 2030 (EU directive from 2018).

If electricity continues to be generated primarily from fossil fuels, increasing electricity consumption implies increasing carbon dioxide emissions. For decarbonization to have a significant effect the takeover of renewables from fossil fuels must be sizeable, reaching where and when needed. Storing the electricity in batteries enables electrification of hard-to-reach communities and delivery of renewables into remote areas administered by fossil fuels. However, revolutionary progress is yet expected in energy-dense storage systems, such as batteries.

In their mission to meet the 2050 climate neutrality goal of the European Green Deal, European Commission published „A hydrogen strategy for climate-neutral Europe“, in July this year, to help define necessary steps towards wide-spread utilization of hydrogen.



Driving the hydrogen!

Quantum Gap: What about the mobile applications of hydrogen fuel cells?

Igor Milanović: Comparison of the life cycle assessment of the hydrogen-powered cars and fossil fuel-powered cars showed that a larger amount of energy is required for the former one. Speaking in terms of pollution, this means that, currently, a larger amount of carbon dioxide is released into the atmosphere as a result of hydrogen-powered car construction and operations.

Quantum Gap: With that in mind, one might assume that hydrogen-powered vehicles will not evolve to their full maturity, yet they are being produced and operative worldwide.

Igor Milanović: Hydrogen-powered trains, buses, trucks, airplanes, and ships are already operational. In 2018. Germany launched the world’s first hydrogen-powered train, operating on a 100 km route between Cuxhaven, Bremerhaven, Bremervoerde, and Buxtehude in northern Germany. I’m also looking forward to seeing the 2020 Toyota Mirai - one of the first cars operative thanks to hydrogen fuel cells - scheduled for release in December this year. In Zagreb, at the Faculty of Mechanical Engineering and Naval Architecture, a hydrogen-powered bicycle was built by a team led by Ankica Kovač.

Three types of hydrogen-powered cars are publicly available in the automotive markets in 2020: the mid-sized Japanese Toyota Mirai, the Honda Clarity Fuel Cell, and the South Korean Hyundai Nexo, which is the only hydrogen-powered SUV.

One of the first mass-produced battery-powered automobiles is the Toyota Mirai, which is a hydrogen fuel cell vehicle with two tanks storing hydrogen at 70 MPa, of about 5 kg capacity. Toyota Mirai has a range of about 500 km on a fuel tank, with approximately 5 minutes refueling time.

The leading shortcoming of hydrogen-fueled cars is the refueling station's sparsity, which is why potential drivers are often hesitant prior to purchase.


Quantum Gap: Elon Musk, who built an empire around lithium-ion batteries and electric cars, disagrees with the potential of hydrogen fuel cells to the extent of calling them „fool sells“. He gives an advantage to electric cars that appeared easier to commercialize. Is he right or is he talking out of fear of competition? Is the level of mobile hydrogen-power complexity deemed to remain greater than that of lithium-ion or is there research and technological potential worth developing?

Igor Milanović: Actually, he is advertising lithium-ion batteries which are installed in Tesla cars. I think that, in the future, both solutions will be implemented in the application: hydrogen driven cars and battery-driven cars. Now, the implementation of lithium-ion batteries is oriented for mobile purposes while hydrogen storage coupled with fuel cell technology is oriented for stationary purposes. In the near future, we will have numerous solutions for mobile applications with fuel cell technology. For example, mentioned FC train in Germany.

Lithium-ion batteries used, for example, in laptops or mobile phones store energy in a short-duration interval for a matter of days or hours. Hydrogen, on the other hand, contains over three times the energy per unit of mass than a lithium-ion battery. Regarding mobile applications, the future development of hydrogen fuel cells promises vehicle reservoirs with dimensions similar to gasoline cars.


Hydrogen as a carrier!

Quantum Gap: Hydrogen itself is not a source of energy, but its carrier, meaning it has to be produced from available resources - water or natural gas - using an energy-conversion process like electrolysis to split water into hydrogen and oxygen or reforming of natural gas. This raises the question of storing the produced hydrogen for later use. What is the convenient storage method for mobile-specific applications?

Igor Milanović: Hydrogen can be stored in three states of aggregation: gaseous, liquid, and solid form. There are several forms of solid hydrogen storage methods: chemical (in metal hydrides, complex hydrides), intermetallics (hydrogen storage in interlayers between intermetallic structure) and physical (physisorption materials, MOFs). In the last 10 years, metal-organic frameworks (MOFs) were very interesting for investigation, as a part of material containing a large enough active surface. Unfortunately, they require cryogenic temperatures for quality physisorption. Liquid storage of hydrogen is quite efficient and enables large energy density, but servicing the equipment and maintaining the cryogenic temperatures is an undertake requiring large containers, which makes things rather difficult. Storage of hydrogen in steel tanks under pressure (of seven hundred bars) is a cheap but not a safe way of storing.

Quantum Gap: An alternative storage method would be..?

Igor Milanović: A research perspective is a solid-state storage of hydrogen in the form of metal hydrides. They also exhibit respective insufficiencies, such as extremely high stability, but other characteristics are very promising.

Quantum Gap: Which chemical elements or materials are most qualified to form hydrides for solid-state hydrogen storage?

Igor Milanović: We have worked with magnesium hydride (MgH2), which is an inexpensive chemical compound made simply from magnesium powder. Pure magnesium can be obtained from several active mines in Serbia - this being the additional positive in advocating for more hydrogen energy-based research projects to be performed in Serbia.

The trouble with magnesium hydride is its overall stability and the resulting difficulty of hydrogen desorption, which raises the price of full equipment.

Quantum Gap: Any proposed solution to the issue of magnesium hydride’s stability?

Igor Milanović: As a result, magnesium hydride is never used in its pure form; it is modified with additives - intermetallics, oxides, noble or transition metals - to accelerate the hydrogen desorption kinetics and lower the temperature of hydrogen desorption.

Quantum Gap: How do you achieve the desired modification?

Igor Milanović: By grinding of a combined magnesium hydride powder and additives in a mill with mechanical balls, which is also a relatively inexpensive process. At the VINČA Institute, in the Laboratory for physics, we have this equipment for preparing and analyzing milligrams to gram samples, but for large-scale industrial production, it is imperative to have apparatus that upholds samples to about kilograms.


How much do you know about hydrogen energy? - Renewables Quiz

Quantum Gap: Is society aware of hydrogen energy, its positive aspects, and fuel cell potential?

Igor Milanović: Absolutely not! Media coverage of that technology is scarce. People hardly heard of hydrogen energy or fuel cells, which are, actually, invented during the sixties for the Apollo space program. The Appolo Command Module’s source of electricity was a set of fuel cells, where hydrogen and oxygen were combined to produce electricity, and the only co-product was drinkable water.

Quantum Gap: When and how did you first hear about fuel cells?

Igor Milanović: First time I read about fuel cells was in the magazine Politikin zabavnik, when I was in high school. My team at CONVINCE is advocating for the full inclusion of a stand-alone faculty course on fuel cells and hydrogen energy within the curriculum of the Faculty of physical chemistry at the University of Belgrade.

Nearly 1 billion people worldwide lack total electricity access or are powered by unstable and overburdened power grids.                                               


Quantum Gap: Going beyond the hydrogen economy, can you estimate which technologies will dominate the global renewable energy markets?

Igor Milanović: Solar panels and wind turbines will have a lead role as energy generators. A great example of solar and wind superiority is Denmark, which as a world-leading country in wind energy and wind turbine production has over 100% of their energy needs covered from these sources.

In October this year, Australia announced a major renewable energy development project of the world’s largest solar power farm built at the remote cattle station in the Northern Territory. The concept of the project, „exporting sunshine“ is based on the Australian vast solar energy resources. Approximately, 10 gigawatts of photovoltaic panels, spread across the huge territory and, even, visible from space, will be used for securing and exporting solar energy.



Here vs there, feat. Then vs now

Quantum Gap: Back to the roots. You started working on your Ph.D. at the Vinča Institue in 2009. Could you have imagined your career would turn out the way it did?

Igor Milanović: I believe we have matching perspectives and you are asking me a question you know the answer to. Needless to say, we didn’t imagine our careers would go in this direction. 

Quantum Gap: How did you imagine it?

Igor Milanović: I imagined doing my job honorably and being reasonably paid for it. The problem is multi-dimensional, but at its core, it amounts to resources – financial, lack of equipment, or possibilities.

Quantum Gap: You have an ongoing collaboration with the Ruđer Bošković Institute in Zagreb, Croatia, where you spent time working on a postdoc project. How long were you there?

Igor Milanović: Over two years, if I’m correct. I established a great working relationship and later a friendship with Nikola Biliskov.

Quantum Gap: Speaking of Zagreb, where is Belgrade in respect to their science? Money, equipment...

Igor Milanović: We were on a similar path until four or five years ago when they became an EU member state. They gained support from the EU and open access to EU projects, also they received a promise of support from the Croatian government. Projects supported by successful scientific groups and individuals enabled them to build new labs and further development in the infrastructural aspect.

Quantum Gap: Stories about major scientific discoveries in the past repeatedly implied a solitary scientist isolated from the world, working to understand the incomprehensible or invent the unthinkable. Nowadays, however, collaboration and mobility among scientists are accentuated. Would you say scientific work is easier in collaboration and, if so, why is that?

Igor Milanović: Of course. For me, good scientific work is in direct correlation with permanent collaboration and communication with other colleagues. Nowadays is even easier to communicate with people in whole parts of the World than in the past. In my opinion, new ideas are created in sincere observation of the problem. A Group of people can perceive one problem from many angles. That is an advantage.

Quantum Gap: What is the essential prerequisite for a good collaboration?

Igor Milanović: People and their desire to introduce changes in every aspect of their lives.

Quantum Gap: From your point of view, how do you become recognized in the world of science, in Serbia or abroad?

Igor Milanović: I think you can become successful and recognized only if you go abroad, do something distinguished, and then return home. Or if you acquire political connections. Nevertheless, you should have professional evidence supporting your work.

Quantum Gap: Is there an alternative path?

Igor Milanović: An alternative is swimming in commercial waters, where you make a product that sells, from which you build an image.

Quantum Gap: Based on your experience, would you recommend a science career to your offspring?

Igor Milanović: Hm, well, the level of frustration among scientists in the Balkans is substantial, so from that perspective, one cannot grasp a science career objectively.

Quantum Gap: You think the situation is different somewhere else, in Britain for example?

Igor Milanović: I would say that corruption is present everywhere, but it is shifted to the level of bosses or individuals dealing directly with money. On the basic level, the system works, basic working conditions are far better, and you are allowed to converge to a point in your career.


Igor's academic info

CV      Orcid      Scopus      Google Scholar      ResearchGate      LinkedIn