1. Activity data and methods for German Biogas reporting
© m.paterson
Activity data and methods for German Biogas reporting
Sebastian Wulf, Sven Grebe, Dieter Haenel, Claus Rösemann
Krakow, May 11th, 2017

2. Sources of emissions in AD
(CO2)
CH4
(CO2)
CH4
CH4
CHP
CH4
NH3
Fermenter
N2O
CH4
NH3 PS
storage
N2O
NH3

3. digestate storage / processing
System boundaries
sewage treatment
gas capture
landfills
CHP
electricity/heat
biowaste
gas processing
Bio-methane
energy crops
Flare
biogas production
slurry, solid manure
digestate storage / processing
Agriculture
application
fertilizer
Waste 2
Energy

4. Calculation methodology
Waste sector
Calculation from official statistics on treated waste products
Cumulated emission factors including storage before digestion, storage and application of digestates.
Agricultural sector
No official statistics on input data available
Tier 3 Method used for calculation

5. Methodology – CH4 Important parameters:
Overall input of organic carbon (VSdig)
Methane production potential of the input material(Bo)
Residual gas potential as share of Bo (µrg)
Leakage rate from the fermenter/gas tight system (Lprod/Lsto,gt)
Relative share of gastight storage (xgts)
60-70% in Germany

6. Methodology – NH3
Per definition = 0 for fermenter and gastight storage
for storage without cover emission factor equals slurry storage (with crust)
Changes in TAN-content during digestion is accounted for
Slurries: Survey showed, that mean TAN rises from 45% to 62%
fTAN = 0.32
Energy crops: mean TAN of digestates from energy crops: 56 % of Ntot .
fTAN = 0.56

7. Activity data needed
Amount of nitrogen (and VS) entering the biogas plant
Amount of animal manures entering biogas plant („saved emissions“)
Relative share of gas tight storage
Information needed on:
different input materials into digestion
conditions of digestate storage
No official statistics available

8. Data sources used Data from grid operators (Übertragungsnetzbetreiber)
Amount of electricity fed into the grid by individual plants
Code giving information on the feed-in tariff for the individual plant -> identification of biogas-plants possible (in most cases)
Survey of a private company on input subtrates into 1660 German biogas plants ( )
Bo (potential CH4 yield of substrates) -> good availability for manure an energy crops
Survey of DBFZ (German Biomass Research Centre): Data on digestate storage (2012)

9. Substrate input
Substrate input into German biogas plants needs differentiation between:
Federal states:
In some states larger share of manure input (e.g. Thuringia), in others larger share of energy plants (Lower Saxony and Saxony Anhalt)
16 federal states
Size of biogas plants:
In smaller plants larger share of manure input
5 plant size groups
Type of substrates:
Cattle, pig slurry and poulty manure (in order to account für „saved emissions“ in these animal categories)
Different gas yields (in order to calculate mass of input from energy production)
10 substrate types

10. Substrate input Specific gas yield of substrates
Electrical efficiency of CHP
Substrate mix (per plant size and federal state)
Electricity produced (per plant size and federal state)
mass of different substrates being used (per federal state)
N-input with different substrates into AD (per federal state)
N-content of substrates

11. Share of gas-tight storage
Survey data (DBFZ) for 2012 does not apply to current status.
Change in renewable energy act > all new plants need gas-tight storage
Data needed for calculation:
For each plant size group and federal state:
Number of plants operating 2012: O2012
Number of individual plants not operating in 2015 compared to (closed plants): C2015
Numbers of plants operating in 2015: O2015

12. Share of gas-tight storage
Number of plants operating 2015 (initial operation before 2012):
P2015_old = O C2015
Xgts from survey for 2012
Number of plants operating 2015 (initial operation after 2012):
P2015_new = O P2015_old
Xgts = 1
Weighing for produced energy of each plant size group:
Xgts per federal state

13. Effect on reported emissions
Increase/decrease of reported emissions, if input is considered of:
(Submission 2015)

14. Effect on reported emissions
Increase/decrease of reported emissions, if input is considered of:
(Submission 2015)