From ae825d82dcebae7ab67f591329fe8e6140a96d72 Mon Sep 17 00:00:00 2001
From: Fabian <fab.hof@gmx.de>
Date: Fri, 26 Jan 2024 12:10:39 +0100
Subject: [PATCH] prepare_sector_network: reorder buses for dac components

---
 doc/release_notes.rst             |  2 ++
 scripts/add_electricity.py        |  2 +-
 scripts/prepare_sector_network.py | 22 +++++++++++-----------
 3 files changed, 14 insertions(+), 12 deletions(-)

diff --git a/doc/release_notes.rst b/doc/release_notes.rst
index 93d1a268..94d5c55f 100644
--- a/doc/release_notes.rst
+++ b/doc/release_notes.rst
@@ -37,6 +37,8 @@ Upcoming Release
 
 * Add the option to customise map projection in plotting config.
 
+* The order of buses (bus0, bus1, ...) for DAC components has changed to meet the convention of the other components. Therefore, `bus0` refers to the electricity bus (input), `bus1` to the heat bus (input), 'bus2' to the CO2 atmosphere bus (input), and `bus3` to the CO2 storage bus (output).
+
 
 PyPSA-Eur 0.9.0 (5th January 2024)
 ==================================
diff --git a/scripts/add_electricity.py b/scripts/add_electricity.py
index c9e5abca..8a1086bd 100755
--- a/scripts/add_electricity.py
+++ b/scripts/add_electricity.py
@@ -288,7 +288,7 @@ def attach_load(n, regions, load, nuts3_shapes, ua_md_gdp, countries, scaling=1.
 
     ua_md_gdp = pd.read_csv(ua_md_gdp, dtype={"name": "str"}).set_index("name")
 
-    logger.info(f"Load data scaled with scalling factor {scaling}.")
+    logger.info(f"Load data scaled by factor {scaling}.")
     opsd_load *= scaling
 
     nuts3 = gpd.read_file(nuts3_shapes).set_index("index")
diff --git a/scripts/prepare_sector_network.py b/scripts/prepare_sector_network.py
index d24feb79..3ea8c8dd 100755
--- a/scripts/prepare_sector_network.py
+++ b/scripts/prepare_sector_network.py
@@ -710,27 +710,27 @@ def add_dac(n, costs):
     heat_buses = n.buses.index[n.buses.carrier.isin(heat_carriers)]
     locations = n.buses.location[heat_buses]
 
-    efficiency2 = -(
+    electricity_input = (
         costs.at["direct air capture", "electricity-input"]
         + costs.at["direct air capture", "compression-electricity-input"]
-    )
-    efficiency3 = -(
+    )  # MWh_el / tCO2
+    heat_input = (
         costs.at["direct air capture", "heat-input"]
         - costs.at["direct air capture", "compression-heat-output"]
-    )
+    )  # MWh_th / tCO2
 
     n.madd(
         "Link",
         heat_buses.str.replace(" heat", " DAC"),
-        bus0="co2 atmosphere",
-        bus1=spatial.co2.df.loc[locations, "nodes"].values,
-        bus2=locations.values,
-        bus3=heat_buses,
+        bus0=locations.values,
+        bus1=heat_buses,
+        bus2="co2 atmosphere",
+        bus3=spatial.co2.df.loc[locations, "nodes"].values,
         carrier="DAC",
         capital_cost=costs.at["direct air capture", "fixed"],
-        efficiency=1.0,
-        efficiency2=efficiency2,
-        efficiency3=efficiency3,
+        efficiency=-heat_input / electricity_input,
+        efficiency2=-electricity_input,
+        efficiency3=electricity_input,
         p_nom_extendable=True,
         lifetime=costs.at["direct air capture", "lifetime"],
     )