- The European and German Hydrogen Strategies in a Nutshell
- Effects of Natural Gas Containing Hydrogen on Valves
- Support for the Hydrogen Economy – European Projects
- Hydrogen Categorisation by Emission Footprint
- Power to Gas: A Solution, or a Dead End of the German Energy Sector?
- Innovative Design of PE Pipe Materials in the Low-carbon Future
- Rollout of Hydrogen Fuelling Stations in the Czech Republic
- In Brief…
- Other Periodicals
- CNG Motoring – New Fuelling Stations
THE CGA‘S ACTIVITIES
- The Hydrogen Working Group’s Activities
- Memorandum on Cooperation in the Future Decarbonisation of the Heat Supply Industry
- The First Mobile Self-service LNG Fuelling Station in the Czech Republic Put into Operation
- We Are Writing the 100th PLYN Volume
- The Gas Mobility Day in the Photo Gallery
Gas System Calculations Considering Hydrogen
Summary: Considerations of using alternative fuels (biomethane production, hydrogen addition to natural gas, and potential hydrogen transport through pipelines) precipitate the need to examine the feasibility of such solutions from the perspective of gas interchangeability and gas quality monitoring (e.g. GCV) and even the need to cope with the considerably different conditions in pure hydrogen transport. The contribution outlines the computational options for the above situations using the SIMONE system and summarises our experience in this respect, offering an example of the modelling of a system with compression for long-distance transmission of natural gas, a natural gas/hydrogen mixture, and finally of pure hydrogen.
Key words: Hydrogen, natural gas, pipeline gas transmission, modelling
Potential of Hydrogen Production from Renewable Sources
Michal Kocůrek, Martin Paidar
Summary: The expectations related to energy decarbonisation are increasingly focusing on an energy carrier that has been used only very little so far: hydrogen. Storing energy in hydrogen, such energy being usable immediately or over months in many areas of industry, energy and transport, appears to be one of the contributions helping to meet the requirement for the development of zero-emission electricity and gas industries. Not only pilot projects but also national hydrogen strategies (the Netherlands, Germany, and Portugal) are proliferating at the national level in Europe. At the EU level, the European Commission has presented its own strategy for the development of hydrogen use, primarily from renewable energy sources, which is expected to help steer the EU to a decarbonised economy. In the Czech Republic, such documents do not yet exist; let alone an umbrella policy paper clearly specifying the form of and opportunities for hydrogen production from RES and the quantity that can be utilised in the Czech Republic.
Key words: Hydrogen, RES, balancing energy, CO2 emissions
Burning Natural Gas/Hydrogen Mixtures in Household Appliances – Part 1
Josef Fík, Libor Čapla, Jiří Žahourek
Summary: The contribution describes the effect of hydrogen content ranging from 0 to 25 mol % in a mixture with natural gas on burning in household appliances. Gaseous fuels with similar combustion characteristics, in particular Wobbe index and burning velocity, can only be used in a particular household appliance as a substitute. The various chapters describe the effect of hydrogen content in natural gas on the following: Wobbe index, composition of exhaust gases; emissions of CO2, CO and NOx; burning velocity; output of burners/energy demand of appliances, efficiency of appliances; flame stability; and temperature of combustion. Recommendations on hydrogen content in natural gas for household appliances, accepted from reference literature, are set out there. In conclusion, the authors discuss the pluses and minuses of hydrogen content in natural gas and offer recommendations for hydrogen injection into natural gas distribution systems from the perspective of burning these mixtures in household appliances.
Key words: Household appliances, burning, natural gas/hydrogen mixture
Use of Hydrogen in a Combustion Engine with Advanced Combustion
Jiří Vávra, Zbyněk Syrovátka, Michal Takáts, Jan Macek
Summary: A hydrogen fueled experimental single cylinder engine with cylinder displacement 375 cm3 was tested in steady state operation on an engine test bed. The engine was operated in a low-temperature combustion mode with a lean mixture with the air excess ratio between 2.6 and 3.0. In this way the engine was able to operate free of irregular combustion phenomena. At the same time the engine reaches high thermal efficiency. Molar fraction of NOx below 10 ppm was achieved within the whole range of operational points. Low-temperature combustion therefore shows a potential to comply with contemporary as well as future limits of NOx emission without exhaust gas aftertreatment. Specific emission of CO2 even involving the CO2 inflow with intake air was lowered by 2 to 3 orders of magnitude compared to state-of-the-art automotive diesel engines. Emission of other gaseous pollutants as well as emission of particulate matter are negligible.
Key words: Hydrogen Fueled Internal Combustion Engine, Low-Temperature Combustion, Supercharging
Karin Stehlík – HYTEP