diff --git a/config/config.default.yaml b/config/config.default.yaml
index 794b2bae..9f595401 100644
--- a/config/config.default.yaml
+++ b/config/config.default.yaml
@@ -418,10 +418,10 @@ sector:
       heat_loss: 0.0
   heat_pump_sources:
     central:
-    - air
+      - air
     decentral:
-    - air
-    - ground
+      - air
+      - ground
   cluster_heat_buses: true
   heat_demand_cutout: default
   bev_dsm_restriction_value: 0.75
diff --git a/doc/configtables/sector.csv b/doc/configtables/sector.csv
index e14da557..17435a28 100644
--- a/doc/configtables/sector.csv
+++ b/doc/configtables/sector.csv
@@ -6,6 +6,9 @@ industry,--,"{true, false}",Flag to include industry sector.
 agriculture,--,"{true, false}",Flag to include agriculture sector.
 district_heating,--,,`prepare_sector_network.py <https://github.com/PyPSA/pypsa-eur-sec/blob/master/scripts/prepare_sector_network.py>`_
 -- potential,--,float,maximum fraction of urban demand which can be supplied by district heating. Ignored where below current fraction.
+-- progress,--,Dictionary with planning horizons as keys., Increase of today's district heating demand to potential maximum district heating share. Progress = 0 means today's district heating share. Progress = 1 means maximum fraction of urban demand is supplied by district heating
+-- district_heating_loss,--,float,Share increase in district heat demand in urban central due to heat losses
+cluster_heat_buses,--,"{true, false}",Cluster residential and service heat buses in `prepare_sector_network.py <https://github.com/PyPSA/pypsa-eur-sec/blob/master/scripts/prepare_sector_network.py>`_  to one to save memory.
 -- forward_temperature,°C,float,Forward temperature in district heating
 -- return_temperature,°C,float,Return temperature in district heating. Must be lower than forward temperature
 -- heat_source_cooling,K,float,Cooling of heat source for heat pumps
@@ -14,9 +17,10 @@ district_heating,--,,`prepare_sector_network.py <https://github.com/PyPSA/pypsa-
 -- -- heat_exchanger_pinch_point_temperature_difference,K,float,Heat pump pinch point temperature difference in heat exchangers assumed for approximation.
 -- -- isentropic_compressor_efficiency,--,float,Isentropic efficiency of heat pump compressor assumed for approximation. Must be between 0 and 1.
 -- -- heat_loss,--,float,Heat pump heat loss assumed for approximation. Must be between 0 and 1.
--- progress,--,Dictionary with planning horizons as keys., Increase of today's district heating demand to potential maximum district heating share. Progress = 0 means today's district heating share. Progress = 1 means maximum fraction of urban demand is supplied by district heating
--- district_heating_loss,--,float,Share increase in district heat demand in urban central due to heat losses
-cluster_heat_buses,--,"{true, false}",Cluster residential and service heat buses in `prepare_sector_network.py <https://github.com/PyPSA/pypsa-eur-sec/blob/master/scripts/prepare_sector_network.py>`_  to one to save memory.
+-- heat_pump_sources,,,
+-- -- central,--,"Any subset of {ground, air}", Heat pump sources for central heating heat pumps
+-- -- decentral,--,"Any subset of {ground, air}", Heat pump sources for decentral heating heat pumps
+
 ,,,
 bev_dsm_restriction _value,--,float,Adds a lower state of charge (SOC) limit for battery electric vehicles (BEV) to manage its own energy demand (DSM). Located in `build_transport_demand.py <https://github.com/PyPSA/pypsa-eur-sec/blob/master/scripts/build_transport_demand.py>`_. Set to 0 for no restriction on BEV DSM
 bev_dsm_restriction _time,--,float,Time at which SOC of BEV has to be dsm_restriction_value