The decarbonization of electricity production is necessary to achieve the net zero emissions objective in 2050. If photovoltaic, wind, nuclear or hydroelectric power plants make it possible to significantly reduce GHG emissions, thermal power plants powered by natural gas remain essential for, among others, guarantee security of supply in winter. However, they emit on average 418 gCO2eq/kWh, according to the ARCICEN stakeholder guide published on the website of the National Commission for Public Debate. To reduce their environmental impact, Power Service Consulting (PSC) and the German Center for Aeronautics and Astronautics (DLR) decided to upgrade a micro gas turbine so that it can run on hydrogen.
A new combustion chamber
The physical and chemical properties of hydrogen are very different from those of natural gas. The flame speed of H2 is significantly higher and its ignition temperature is significantly lower. To avoid safety problems and possible damage due to heat and shock waves, a solution has been developed. The German Center for Aeronautics and Astronautics has developed a stabilized jet combustion chamberadapted to hydrogen. When designing this new burner, he made sure that the flame did not reach its nozzles and could damage them, according to Martin Hohlocha DLR researcher. Once the development of the device and laboratory tests were completed, the center replaced the old combustion chamber of a 100 kW micro-gas turbine.
Successful tests
Tests of the modernized micro-turbine were carried out in the H2-Container technical center of the DLR in Lampoldshausen. Following the tests, Martin Hohloch said the team managed to start the turbine with pure hydrogen without any problems. The researcher from the German Center for Aeronautics and Astronautics also added that the facility has reached its full operating range and has operated at full power for almost 100 hours.
Concerning pollutant discharges, the concentration of nitrogen oxide was estimated at less than 15 ppm during turbine operation. Which, according to her, is much lower than that of natural gas. For information, Power Service Consulting has developed a mixing and distribution system. This device allows the micro-turbine to be supplied with hydrogen or a mixture of H2 and natural gas.
An economical solution
If modernizing the turbines of gas-fired power plants presents itself as an excellent way to reduce their greenhouse gas emissions, it also constitutes a solution to reduce expenses. Indeed, according to Peter Kutnethe director of the gas turbine department of the DLR Institute of Combustion Technology, it is necessary to budget around 35 million euros and carry out work for almost 6 years to build a 15 MW power plant. On the other hand, modernization only takes a year and costs 1/10ᵉ of the amount necessary to set up a new electricity production site.
It is important to note that currently no power plant can be powered 100% with green hydrogen. Nevertheless, DLR and PSC decided to launch their project to be able to quickly provide a solution production of less polluting electricity, when H2 will be available in sufficient quantity. More information here. The transition to less polluting solutions like hydrogen is underway, what do you think? I invite you to give us your opinion, your comments or point out an error in the text, click here to post a comment.