(Eat) - In December of this year, the Eon subsidiary Avacon in Saxony-Anhalt will start adding hydrogen to a natural gas sub-network. The joint project between Avacon and the German Gas and Water Association (DVGW) is intended to show “that it is technically possible to feed hydrogen into an existing gas network at a significantly higher percentage than previously provided for in the DVGW technical rules”. According to the company, devices and systems do not need to be changed. Laboratory studies showed that many devices in households could be operated with a hydrogen admixture of 30 percent.
Test line network with a length of 35 kilometers
A network section in Jerichower Land was selected. This is particularly suitable because the network infrastructure installed there is representative of the entire Avacon gas distribution network, which makes the results transferable. This is a medium-pressure distribution network with a line length of around 35 kilometers, from which around 350 network customers are supplied with natural gas. With the corresponding number of gas appliances, which are primarily used to supply heat, the area covers a wide range of appliance technology. The devices were recorded in advance and checked for operational and safety reasons as well as for hydrogen compatibility. Four devices proved to be unsuitable and were replaced by new devices that were compatible with hydrogen.
20 percent admixture
The addition of hydrogen will take place over the 2021/22 and 2022/23 heating periods. When it goes into operation at the end of 2021, ten percent of hydrogen will be added to the natural gas in the first stage over about four weeks, which, according to Eon, means that the proportion is still within the mixing level covered by the DVGW regulations. For around a third of the gas appliances, random measurements of the quality of combustion with measurements of the actual hydrogen content would be carried out on site in order to scientifically monitor the feed-in at all feed-in stages.
The maximum hydrogen admixture of up to 20 percent should be achieved gradually in increments of five percent. The 15 percent admixture phase is planned for the first quarter of 2022. 20 percent should be achieved at the end of the heating season. A further 20 percent feed-in phase will follow in the 2022/23 heating season over several weeks.
Photos
Avacon will feed hydrogen into the gas network in Saxony-Anhalt in December. © Eon SE
