Safety requirements related to the end-user equipment

This LAP is concerned with the safety requirements (and design and operational aspects) for commercial and domestic end-user equipment operating with hydrogen gas blends resulting from hydrogen injected and transmitted in the gas grid at the TSO level

Glossary:

The requirements needed to guarantee the safety of the end user application.

select country:

Is it a barrier?

Yes

Type of Barrier

Economic barriers

Assessment Severity

Questions:

Question 1 Is there any legislation with regard to safety requirements related to end-user equipment (e.g.: limits in terms of H2 for use in gas appliances)? If yes, please answer the following question.

a) The most important safety requirement related to the end–user equipment is the obligation of the network operator to carry out an assessment of the grid compatibility after receiving a request for connection. b) UNECE Regulation 110 (Compressed and liquefied natural gas components) and the DIN 51624 establish a threshold of up to 2 Vol.–% hydrogen for the vehicle fuel CNG (compressed natural gas). If a CNG fuelling station is connected to the respective part of the gas grid, the admissible hydrogen concentration must not exceed 2 Vol.–%. c) In the event that no calibrated hydrogen content measuring system (process gas chromatograph) is installed, the hydrogen content must not exceed 0.2 Vol.–% (see the Technical Guideline of the Physical–Technical Federal Institute G 14). d) There is no normative limit for hydrogen admixture for the operation of conventional gas appliances burning gaseous fuels used for cooking, heating, hot water production etc.

Question 2 Changes to gas supply composition may have implications for the design of gas appliances (safety) and the relevant legislation. What are the implications you expect with regard to the possible concentrations of hydrogen in the H2NG blend?

The current research results in Germany show that operation of gas appliances with hydrogen admixture up to 10 vol.% is possible without adaptation of the devices.

Question 3 For which end user applications do you foresee the main consequences and at which level? Could you please provide references to underpin your opinion?

DVGW Worksheet 262 describes threshold values for different gas applications. This relates in particular to the quality of gas and hydrogen concentration required by gas turbines, CHP motors and pore storage facilities as well as the failure to capture hydrogen concentrations using process gas chromatograph (PGS)

Question 4 Changes to gas supply composition may have implications for CNG compression, storage, and use in CNG vehicles. What are the additional safety precautions needed? Could you please provide references to underpin your opinion

There are no additional safety precautions to be foreseen

Describe the comparable technology and its relevance with regard to hydrogen

Biogas

National legislation:

Gas Network Access Ordinance (Gasnetzzugangsverordnung – Gas NZV)
§ 19 Gas quality
(1) The transport customer shall ensure that the gas to be fed into the gas network conforms to the generally recognized rules of technology as defined in §49 (2) of the Energy Industry Act and is compatible with the provisions of paragraph 2.
(2) Compatibility of the gas to be fed is provided when the transport customer supplies the gas at the feed–in point with a specification according to the required characteristics of the gas in the receiving network published on the website of the network operator at the time of feeding.
§ 36 Quality requirements for biogas
(1) The biogas supplier must ensure that the gas at the feed–in point and during the feed–in corresponds to the requirements of the G 260 and G 262 worksheets of the German Association of the Gas and Water Supply(DVGW).
DIN 51624 Automotive fuels – Compressed natural gas – Requirements and test methods
Worksheets DVGW G 260 (Gas quality) DVGW G 262 (Usage of gases from renewable sources in the public gas supply), issued by the German Association for Gas and Water Supply
DVGW G 260 and 262 provide the overall requirements for gases in the public supply grids. Up to 10Vol.–% hydrogen are allowed, if sensitive devices are not connected to the downstream network.