Approximate district heating COPs via Jensen et al. 2018

config/config.default.yaml

@@ -408,6 +408,15 @@ sector:
       2045: 0.8
       2050: 1.0
     district_heating_loss: 0.15
+    # check these numbers!
+    forward_temperature: 90 #C
+    return_temperature: 50 #C
+    heat_source_cooling: 6 #K
+    heat_pump_cop_approximation:
+      refrigerant: ammonia
+      heat_exchanger_pinch_point_temperature_difference: 5 #K
+      isentropic_compressor_efficiency: 0.8
+      heat_loss: 0.0
   cluster_heat_buses: true
   heat_demand_cutout: default
   bev_dsm_restriction_value: 0.75
@@ -490,7 +499,7 @@ sector:
   aviation_demand_factor: 1.
   HVC_demand_factor: 1.
   time_dep_hp_cop: true
-  heat_pump_sink_T: 55.
+  heat_pump_sink_T_individual_heating: 55.
   reduce_space_heat_exogenously: true
   reduce_space_heat_exogenously_factor:
     2020: 0.10  # this results in a space heat demand reduction of 10%

doc/configtables/sector.csv

@@ -6,6 +6,14 @@ 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.
+-- 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
+-- heat_pump_cop_approximation,,,
+-- refrigerant,--,"{ammonia, isobutane}",Heat pump refrigerant assumed for COP approximation
+-- 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.

doc/release_notes.rst

@@ -10,6 +10,8 @@ Release Notes
 Upcoming Release
 ================
 
+* Changed heat pump COP approximation for central heating to be based on Jensen et al. 2018 and a default forward temperature of 90C. This is more realistic for district heating than the previously used approximation method.
+
 * Renamed the carrier of batteries in BEVs from `battery storage` to `EV battery` and the corresponding bus carrier from `Li ion` to `EV battery`. This is to avoid confusion with stationary battery storage.
 
 * Changed default assumptions about waste heat usage from PtX and fuel cells in district heating.

rules/build_sector.smk

@@ -217,13 +217,37 @@ rule build_temperature_profiles:
 
 rule build_cop_profiles:
     params:
-        heat_pump_sink_T=config_provider("sector", "heat_pump_sink_T"),
+        heat_pump_sink_T_decentral_heating=config_provider(
+            "sector", "heat_pump_sink_T_individual_heating"
+        ),
+        forward_temperature_central_heating=config_provider(
+            "sector", "district_heating", "forward_temperature"
+        ),
+        return_temperature_central_heating=config_provider(
+            "sector", "district_heating", "return_temperature"
+        ),
+        heat_source_cooling_central_heating=config_provider(
+            "sector", "district_heating", "heat_source_cooling"
+        ),
+        heat_pump_cop_approximation_central_heating=config_provider(
+            "sector", "district_heating", "heat_pump_cop_approximation"
+        ),
     input:
         temp_soil_total=resources("temp_soil_total_elec_s{simpl}_{clusters}.nc"),
         temp_air_total=resources("temp_air_total_elec_s{simpl}_{clusters}.nc"),
     output:
-        cop_soil_total=resources("cop_soil_total_elec_s{simpl}_{clusters}.nc"),
-        cop_air_total=resources("cop_air_total_elec_s{simpl}_{clusters}.nc"),
+        cop_air_decentral_heating=resources(
+            "cop_air_decentral_heating_elec_s{simpl}_{clusters}.nc"
+        ),
+        cop_soil_decentral_heating=resources(
+            "cop_soil_decentral_heating_elec_s{simpl}_{clusters}.nc"
+        ),
+        cop_air_central_heating=resources(
+            "cop_air_central_heating_elec_s{simpl}_{clusters}.nc"
+        ),
+        cop_soil_central_heating=resources(
+            "cop_soil_central_heating_elec_s{simpl}_{clusters}.nc"
+        ),
     resources:
         mem_mb=20000,
     log:
@@ -233,7 +257,7 @@ rule build_cop_profiles:
     conda:
         "../envs/environment.yaml"
     script:
-        "../scripts/build_cop_profiles.py"
+        "../scripts/build_cop_profiles/run.py"
 
 
 def solar_thermal_cutout(wildcards):
@@ -1017,8 +1041,18 @@ rule prepare_sector_network:
         ),
         temp_soil_total=resources("temp_soil_total_elec_s{simpl}_{clusters}.nc"),
         temp_air_total=resources("temp_air_total_elec_s{simpl}_{clusters}.nc"),
-        cop_soil_total=resources("cop_soil_total_elec_s{simpl}_{clusters}.nc"),
-        cop_air_total=resources("cop_air_total_elec_s{simpl}_{clusters}.nc"),
+        cop_soil_decentral_heating=resources(
+            "cop_soil_decentral_heating_elec_s{simpl}_{clusters}.nc"
+        ),
+        cop_air_decentral_heating=resources(
+            "cop_air_decentral_heating_elec_s{simpl}_{clusters}.nc"
+        ),
+        cop_air_central_heating=resources(
+            "cop_air_central_heating_elec_s{simpl}_{clusters}.nc"
+        ),
+        cop_soil_central_heating=resources(
+            "cop_soil_central_heating_elec_s{simpl}_{clusters}.nc"
+        ),
         solar_thermal_total=lambda w: (
             resources("solar_thermal_total_elec_s{simpl}_{clusters}.nc")
             if config_provider("sector", "solar_thermal")(w)

rules/solve_myopic.smk

@@ -21,8 +21,18 @@ rule add_existing_baseyear:
                 config_provider("scenario", "planning_horizons", 0)(w)
             )
         ),
-        cop_soil_total=resources("cop_soil_total_elec_s{simpl}_{clusters}.nc"),
-        cop_air_total=resources("cop_air_total_elec_s{simpl}_{clusters}.nc"),
+        cop_soil_decentral_heating=resources(
+            "cop_soil_decentral_heating_elec_s{simpl}_{clusters}.nc"
+        ),
+        cop_air_decentral_heating=resources(
+            "cop_air_decentral_heating_elec_s{simpl}_{clusters}.nc"
+        ),
+        cop_air_central_heating=resources(
+            "cop_air_central_heating_elec_s{simpl}_{clusters}.nc"
+        ),
+        cop_soil_central_heating=resources(
+            "cop_soil_central_heating_elec_s{simpl}_{clusters}.nc"
+        ),
         existing_heating_distribution=resources(
             "existing_heating_distribution_elec_s{simpl}_{clusters}_{planning_horizons}.csv"
         ),
@@ -77,8 +87,18 @@ rule add_brownfield:
         + "prenetworks/elec_s{simpl}_{clusters}_l{ll}_{opts}_{sector_opts}_{planning_horizons}.nc",
         network_p=solved_previous_horizon,  #solved network at previous time step
         costs=resources("costs_{planning_horizons}.csv"),
-        cop_soil_total=resources("cop_soil_total_elec_s{simpl}_{clusters}.nc"),
-        cop_air_total=resources("cop_air_total_elec_s{simpl}_{clusters}.nc"),
+        cop_soil_decentral_heating=resources(
+            "cop_soil_decentral_heating_elec_s{simpl}_{clusters}.nc"
+        ),
+        cop_air_decentral_heating=resources(
+            "cop_air_decentral_heating_elec_s{simpl}_{clusters}.nc"
+        ),
+        cop_air_central_heating=resources(
+            "cop_air_central_heating_elec_s{simpl}_{clusters}.nc"
+        ),
+        cop_soil_central_heating=resources(
+            "cop_soil_central_heating_elec_s{simpl}_{clusters}.nc"
+        ),
     output:
         RESULTS
         + "prenetworks-brownfield/elec_s{simpl}_{clusters}_l{ll}_{opts}_{sector_opts}_{planning_horizons}.nc",

rules/solve_perfect.smk

@@ -19,8 +19,18 @@ rule add_existing_baseyear:
                 config_provider("scenario", "planning_horizons", 0)(w)
             )
         ),
-        cop_soil_total=resources("cop_soil_total_elec_s{simpl}_{clusters}.nc"),
-        cop_air_total=resources("cop_air_total_elec_s{simpl}_{clusters}.nc"),
+        cop_soil_decentral_heating=resources(
+            "cop_soil_decentral_heating_elec_s{simpl}_{clusters}.nc"
+        ),
+        cop_air_decentral_heating=resources(
+            "cop_air_decentral_heating_elec_s{simpl}_{clusters}.nc"
+        ),
+        cop_air_central_heating=resources(
+            "cop_air_central_heating_elec_s{simpl}_{clusters}.nc"
+        ),
+        cop_soil_central_heating=resources(
+            "cop_soil_central_heating_elec_s{simpl}_{clusters}.nc"
+        ),
         existing_heating_distribution=resources(
             "existing_heating_distribution_elec_s{simpl}_{clusters}_{planning_horizons}.csv"
         ),

scripts/add_existing_baseyear.py

@@ -419,11 +419,11 @@ def add_heating_capacities_installed_before_baseyear(
     n,
     baseyear,
     grouping_years,
-    ashp_cop,
-    gshp_cop,
-    time_dep_hp_cop,
+    cop: dict,
+    time_dep_hp_cop: bool,
     costs,
     default_lifetime,
+    existing_heating: pd.DataFrame,
 ):
     """
     Parameters
@@ -435,13 +435,13 @@ def add_heating_capacities_installed_before_baseyear(
         currently assumed heating capacities split between residential and
         services proportional to heating load in both 50% capacities
         in rural buses 50% in urban buses
+    cop: dict
+        Dictionary with time-dependent coefficients of performance (COPs) for air and ground heat pumps as values and keys "air decentral", "ground decentral", "air central", "ground central"
+    time_dep_hp_cop: bool
+        If True, time-dependent (dynamic) COPs are used for heat pumps
     """
     logger.debug(f"Adding heating capacities installed before {baseyear}")
 
-    existing_heating = pd.read_csv(
-        snakemake.input.existing_heating_distribution, header=[0, 1], index_col=0
-    )
-
     for name in existing_heating.columns.get_level_values(0).unique():
         name_type = "central" if name == "urban central" else "decentral"
 
@@ -457,12 +457,11 @@ def add_heating_capacities_installed_before_baseyear(
         # Add heat pumps
         costs_name = f"decentral {heat_pump_type}-sourced heat pump"
 
-        cop = {"air": ashp_cop, "ground": gshp_cop}
-
-        if time_dep_hp_cop:
-            efficiency = cop[heat_pump_type][nodes]
-        else:
-            efficiency = costs.at[costs_name, "efficiency"]
+        efficiency = (
+            cop[f"{heat_pump_type} {name_type}"][nodes]
+            if time_dep_hp_cop
+            else costs.at[costs_name, "efficiency"]
+        )
 
         too_large_grouping_years = [gy for gy in grouping_years if gy >= int(baseyear)]
         if too_large_grouping_years:
@@ -639,29 +638,43 @@ def add_heating_capacities_installed_before_baseyear(
     )
 
     if options["heating"]:
-        time_dep_hp_cop = options["time_dep_hp_cop"]
-        ashp_cop = (
-            xr.open_dataarray(snakemake.input.cop_air_total)
-            .to_pandas()
-            .reindex(index=n.snapshots)
-        )
-        gshp_cop = (
-            xr.open_dataarray(snakemake.input.cop_soil_total)
-            .to_pandas()
-            .reindex(index=n.snapshots)
-        )
-        default_lifetime = snakemake.params.existing_capacities[
-            "default_heating_lifetime"
-        ]
+
         add_heating_capacities_installed_before_baseyear(
-            n,
-            baseyear,
-            grouping_years_heat,
-            ashp_cop,
-            gshp_cop,
-            time_dep_hp_cop,
-            costs,
-            default_lifetime,
+            n=n,
+            baseyear=baseyear,
+            grouping_years=grouping_years_heat,
+            cop={
+                "air decentral": xr.open_dataarray(
+                    snakemake.input.cop_air_decentral_heating
+                )
+                .to_pandas()
+                .reindex(index=n.snapshots),
+                "ground decentral": xr.open_dataarray(
+                    snakemake.input.cop_soil_decentral_heating
+                )
+                .to_pandas()
+                .reindex(index=n.snapshots),
+                "air central": xr.open_dataarray(
+                    snakemake.input.cop_air_central_heating
+                )
+                .to_pandas()
+                .reindex(index=n.snapshots),
+                "ground central": xr.open_dataarray(
+                    snakemake.input.cop_soil_central_heating
+                )
+                .to_pandas()
+                .reindex(index=n.snapshots),
+            },
+            time_dep_hp_cop=options["time_dep_hp_cop"],
+            costs=costs,
+            default_lifetime=snakemake.params.existing_capacities[
+                "default_heating_lifetime"
+            ],
+            existing_heating=pd.read_csv(
+                snakemake.input.existing_heating_distribution,
+                header=[0, 1],
+                index_col=0,
+            ),
         )
 
     if options.get("cluster_heat_buses", False):