city : resources
Hydrogen city 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 refining 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 significantly 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 first 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
Source: Siemens Energy – koncept bezemisního řešení pro města
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