European biomethane standards for grid injection and vehicle fuel use

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1 European biomethane standards for grid injection and vehicle fuel use Biosurf Workshop 5 December 2017, Amsterdam Dr Arthur Wellinger European Biogas Association

2 CEN TC 408 In the framework of Biosurf, EBA participated in the CEN Technical Committee establishing a standard on Natural gas and biomethane for use in transport and biomethane for injection in the natural gas network Part 1: Specifications for biomethane for injection in the natural gas network (EN Part 1) Part 2: Automotive fuel specifications (EN Part 2) Both standards were formally accepted in Nov 2016 resp. March 2017

3 EN 16723

4 Why do we need a European Biomethane Standard? Mandate was given by DG Energy Unit C2 on the background that: The number of NGV s was continuously increasing All biomethane producing countries (and even some others) had standards for injection but they were all different Standardization brings legal and technical security Allows easier market access Is a helpful precondition for free trade

5 Development of Biomethane upgrading Plants

6 Number of vehicles and filling stations (2016) EU countries Light Vehicles Buses Trucks All European NGV countries Italy Germany Sweden Switzerland France Country Number of CNG filling stations Italy Germany 913 Austria 173 Sweden 169 Netherlands 162 Switzerland 136 Total Source: CNG Europe

7 Scope of the work and mandate Scope : Standardisation of biomethane Specifications for use as vehicle fuel and injection in natural gas grid. CEN/TC 408 did not focus on the biomethane production process or source nor on the origin of the source.

8 Biomethane Processes Anaerobic digestion followed by biogas upgrading Gasification of renewable organic matter followed by syngas conversion to biomethane Power-to-Gas: producing methane fuel from biogenic carbon or utilizing biological pathways

9 Mandate M/475 EN (grid injection)

10 Mandate M/475 FprEN Mandate M/475 EN Requirements, limit values and related test methods for natural gas and biomethane as automotive fuels with normal MN grade (methane number 65 as in EN 16726) At the time, the limit values are the same for higher MN grades (methane number 80 or higher)

11 Mandate M/475 EN A range of limit values for siloxanes is proposed for this standard: Boiler tests (biogas only): 0,10 mg Si/m3 Analytical measurement: 0,30 mg Si/m3. No mitigating effects of dilution of injected biomethane considered Low value only for direct fueling Higher value of 1mg/m3 for grid injection

12 DNV GL report on effect of siloxanes Silica deposits inside engine cylinder Silica deposition on a heat exchanger of a domestic boiler and Ionization probe

13 DNV GL report on effect of siloxanes Switching type lambda sensors

14 DNV GL report on effect of siloxanes For a test period of about 2 months the VW Caddy Maxi was operated under realistic operating conditions following drive cycles representing different driving behaviour Summary of experimental conditions during final endurance test The results were rather positive despite the extreme conditions chosen

15 DNV GL report on effect of siloxanes During the experiment, the conversion of NOx and CO by the catalyst was not affected by the silica deposition A white deposit was found on the spark plugs, but no misfires were observed A close examination of the cylinder revealed that the cylinder head and valves show grey deposits. The compression ratio was not affected by this deposit. The silicon content in the lubrication oil increased with the amount of silica formed SiO2 was formed, corresponding to a maximum silicon fraction of mg Si/m3n. The wide band type lambda sensor installed upstream of the catalyst and the switching type lambda sensor after the catalyst did not fail during the experiments

16 Limits of Hydrogen In most of the grids 10% hydrogen would not be a problem but Underground porous rock storage: hydrogen is a good substrate for sulphate reducing bacteria Clogging of cavern storage Steel tanks have a limit value of 2% H2 Gas turbines <1% (>5% is possible) Gas engines <2% (up to 10% possible) Source: Altfeld

17 Mandate CEN/TC 234 WG 11 EN16726:2015 EN is the standard for natural gas in the grid. It is also applicable for values after grid injection of biomethane. Relative density Sulphur content Carbon dioxide Dew point Methane Number (MN) Crucial for biomethane is the oxygen limit: or 1 At network entry points and interconnection points the mole fraction of oxygen shall be no more than 0,001 % (24 h average). Where the gas can be demonstrated not to flow to installations sensitive to higher levels of oxygen, e.g. underground storage systems, a higher limit of up to 1 % may be applied.

18 Open questions Wobbe-Index Sulphur content Siloxanes Hydrogen Health (EN 16726:unsolved discussion on band width) (EN 16726: Unsolved discussion on odorization, etc) (EN 16723: OEM s vs analysis vs production) (ongoing discussion in several CEN groups) (Sulphur emission, bacterial danger)

19 H2020 Research project by CEN TC 408 Impact of siloxanes on heavy duty engines Impact of Sulphur on catalytic converters and performance of engines Impact of oxygen on underground storages Impact of components on health

20 Thank you Dr Arthur Wellinger Senior Advisor European Biogas Association Renewable Energy House Rue d'arlon B Brussels info@european-biogas.eu