Table 1 Selection criteria for BP clusters

1

Minimum installed electrical equivalent capacity (P_inst) of each BP in a cluster

 ≥ 375 kW

[26,27,28]

2

Distance of all BPs to natural gas grid

 ≤ 10 km

[27]

3

Distance of BPs to a potential biogas upgrading facility (feed-in point) within a cluster

 ≤ 10 km

[27]

4

Sum of P_inst of all BP within the cluster

 ≥ 5 MW

[29]