Table 1 Description of the collected data for empirical analysis
Data source | Variable | Abbreviation | Level | Unit |
|---|---|---|---|---|
Helmholtz-Centre for Environmental Research (UFZ) | Number of newly established biogas plants in county x, in year t | \({\mathrm{BP}}_{x.t}\) | County | – |
Installed capacity of i newly established biogas plants in county x, in year t | \({\mathrm{IC}}_{x.t}^{i}\) | Biogas Plant | kW/h | |
Regional Statistics Database of Germany [53] | Headcount of cattle in county x, in year t | \({\mathrm{Cattle}}_{x,t}\) | County | Head |
Headcount of pigs in county x, in year t | \({\mathrm{Pig}}_{x,t}\) | County | Head | |
Area of cultivated silage maize in county x, in year t | \({\mathrm{Maize}}_{x,t}\) | County | ha | |
Area of grassland in county x, in year t | \({\mathrm{Grassland}}_{x,t}\) | County | Ha | |
Disposable per capita income in county x, in year t | \({\mathrm{DI}}_{x,t}\) | County | € | |
Average transaction-based land price in county x, in year t | \({LP}_{x,t}\) | County | €/m2 | |
Statistical Office of Saxony [64] Statistical Office of Saxony-Anhalt [65] Statistical Office of Thuringia [66] | Proportion of seats in Kreistag parliament held by SPD and Bündnis 90/Die Grünen in county x, in year t | \({\mathrm{GN}}_{x,t}\) | County | – |
Total valid votes in Landtag parliamentary election in county x, in year t | \({\mathrm{TV}}_{x,t}\) | County | – | |
Total valid votes for Bündnis 90/Die Grünen in Landtag parliamentary election in county x, in year t | \({\mathrm{VG}}_{x,t}\) | County | – | |
Agency for Renewable Resources [67] | Annual cattle excrement electricity generation rate per headcount | \({\mathrm{EGR}}_{C}\) | - | kWh/head |
Annual pig excrement electricity generation rate per headcount | \({\mathrm{EGR}}_{P}\) | – | kWh/head | |
Annual maize electricity generation rate per hectare | \({\mathrm{EGR}}_{M}\) | – | kWh/ha | |
Annual grassland electricity generation rate per hectare | \({\mathrm{EGR}}_{G}\) | – | kWh/ha | |
German Biomass Research Center (DBFZ) [68] | Proportion of biogas plants with livestock as substrate | \({\mathrm{SubPro}}_{L,t}\) | National | – |
Proportion of biogas plants with feedstock as substrate | \({\mathrm{SubPro}}_{EC,t}\) | National | – | |
Federal Statistical Office of Germany [69] | Index of producer prices of agricultural products in year t | \({\mathrm{PPAP}}_{t}\) | National | – |