Hydrogen city

Hydrogen city Source: Siemens Energy – koncept bezemisního řešení pro města

HYDROGEN IS, AS IS WELL KNOWN, THE MOST COMMON ELEMENT IN THE UNIVERSE. HOWEVER, ITS DISADVANTAGE IS RELATED TO THE FACT THAT IT PRACTICALLY DOES NOT OCCUR INDEPENDENTLY, BUT ALMOST EXCLUSIVELY CONNECTS WITH OTHER ELEMENTS. ITS BEST-KNOWN COMPOUND ON EARTH IS WELL KNOWN H2O. BY BURNING HYDROGEN, A LARGE AMOUNT OF ENERGY (96-120 MJ PER 1 KG OF HYDROGEN) CAN BE OBTAINED WITHOUT THE FORMATION OF GREENHOUSE GASES.

: Hydrogen is (literally) everywhere

In addition to the general extension already mentioned, it is appropriate to look at hydrogen not as a fuel, such as oil, natural gas, or coal, but primarily as an energy carrier. Compared to liquid molecules of petrol or diesel, hydrogen molecules bind almost 1.6 times more energy per unit mass. At the same time, global demand for hydrogen is growing, more than tripling between 1980 and 2018, and in 2050 is expected to cover up to 24% of global energy demand, with a market of around € 630 billion a year. Approximately 70 million tonnes of hydrogen are currently used globally, mainly in the oil refi ning and chemical industries. The main positive of hydrogen is that no CO2 emissions are produced during its combustion, while the negative is that hydrogen is currently produced almost exclusively from fossil fuels, with which, on the contrary, CO2 emissions are signifi cantly associated.

Thanks to its properties, hydrogen is used in several areas, among the four most important can be named

· Energy applications · Clean mobility · Decarbonization · Industry

Leaving aside industrial use, which does not play a primary role in the context of smart green cities, it makes sense to focus on the fi rst three.

: Energy

As mentioned above, hydrogen is an excellent medium for energy storage. The advantage, for example, over battery storage systems is cheaper scalability and the possibility of long-term storage over a period of months to years with minimal

energy loss. Even though the hydrogen molecule is very small and easily permeates materials, today‘s technologies manage the production of containers so that no losses occur.

The relationship between hydrogen and batteries is sometimes sharpened, in my opinion unnecessarily, it is necessary to take them as complementary technologies, when they complement each other very well with a suitably chosen strategy. Hydrogen is and will increasingly be an integral part of the energy mix in the future.

It is also important to look at hydrogen from an energy security perspective. It is the possibility of long-term energy storage, especially surpluses from RES, if we are talking about green hydrogen, provides the basis for building energy security in critical urban infrastructure - hospitals, rescue services, support for basic functions of the community, city, or region, etc.

The South Moravian Region alone owns about 3,000 buildings. Not all of them are suitable for solar power plants, but if it only makes sense for some of them, we suddenly have a relatively large production capacity. It does not necessarily have to be consumed at the time of production, moreover, in today‘s time of uncertain occupation (transfer of many workers to the home offi ce) and the associated lower consumption, long-term storage of surpluses is a logical step. Another example can be schools - during the highest exposure in the summer months, empty even outside the pandemic and with minimal consumption, the stored surpluses can then be consumed, for example, in the winter. And all this at the cost of lower effi ciency than battery systems, where the advantage of long-term storage may outweigh the overall balance. Therefore, it is necessary to design correctly and possibly choose a combination of hydrogen and battery technology.

: Clean mobility

Another large stone, rather than a brick, in the jigsaw puzzle of the hydrogen of the future is its use in transport. The primary driver will not be passenger transport, but primarily urban and freight transport. Only after the development of these areas and the related infrastructure, which, unlike other countries in the world and in Europe, does not yet exist, can we expect the development of personal hydrogen mobility. Where there is no chicken, there can be no egg.

The creation of a suitable infrastructure is therefore essential and should be a priority not only of the state where certain activities are already taking place, although they cannot yet be considered suffi cient, but also at the level of regions and municipalities. According to the current National Action Plan for Clean Mobility, 80 hydrogen fi lling stations, 870 buses and up to 50,000 vehicles are expected in the Czech Republic in 2030, although most of them will be urban and freight transport. The fi rst hydrogen „pumps“ are to be built in 2021 in Prague and Litvínov, followed by Brno and again in Prague in 2022 and Pilsen a year later. A good start, but the question is whether the goal of 80 stations in 2030 will be met at this pace.

Once at least the basic infrastructure of hydrogen fi lling stations has been established, the development of personal hydrogen mobility can also be expected. It is a clean and ecological variant of passenger transport with minimal impact on the environment, even if we include the carbon footprint of the production process and possible subsequent recycling in the entire life cycle. There are already several mass-produced models and brands (Toyota, Hyundai) and it can be expected that many more will be added in the coming years - by 2025 it should be Honda, Daimler and BMW. Today, the range is up to 800 km and the fi lling time is about 5 minutes.

There are currently almost 200 hydrogen fi lling stations in Europe, of which 90 are in Germany and another 40 will operate by 2021, with the United Kingdom having even more ambitious plans.

Within urban transport planning, it makes sense to build central nodes connecting urban transport with the possibility of fi lling for cars, ideally the proximity or connection to the local railway network, where there are already several hydrogen solutions in the world. So far, the Moravian-Silesian Region is the most advanced in this area in the Czech Republic.

: Decarbonization

The third major application for the use of hydrogen on the way to solutions to reduce overall greenhouse gas emissions and smart green cities is decarbonisation. Hydrogen can be used in a chemical process to eliminate CO2, which results in methane, i.e., an energy raw material that can be directly consumed or pushed into the gas transmission system in each locality. This applies to all polluters who emit CO2 and today fall under the system of buying allowances - but they do not really solve the situation, they just postpone the problem. In Europe alone, there are around 14,000 businesses. Imagine a solution where these companies, many of them owned by cities or regions, together with private or again urban biogas, use hydrogen and instead of greenhouse gas emissions and other costs in the form of allowances will produce methane…

: The hydrogen future?

Yes, the question is just how fast and to what extent. However, we cannot avoid hydrogen, the breadth of its use from energy, industry through mobility to ecology is so wide that sooner or later it will aff ect everyone. It will benefi t those who prepare for its arrival and begin to think today about incorporating hydrogen into strategic plans for future development. Hydrogen will certainly not work well in stand-alone isolated applications, but eff ectively only where it will be part of the whole concept of smart, green and energy self-suffi cient cities and regions.