From d976a8faf7af42e97ac3b35badccbd02fc269cd5 Mon Sep 17 00:00:00 2001
From: Fabian Neumann <fabian.neumann@outlook.de>
Date: Wed, 7 Jul 2021 17:58:47 +0200
Subject: [PATCH] add CO2 network [first draft]

---
 config.default.yaml               |  1 +
 scripts/prepare_sector_network.py | 58 +++++++++++++++++++++++++------
 2 files changed, 49 insertions(+), 10 deletions(-)

diff --git a/config.default.yaml b/config.default.yaml
index 5f1fa1b8..ecadc3c0 100644
--- a/config.default.yaml
+++ b/config.default.yaml
@@ -214,6 +214,7 @@ sector:
   SMR: true
   co2_sequestration_potential: 200  #MtCO2/a sequestration potential for Europe
   co2_sequestration_cost: 20   #EUR/tCO2 for transport and sequestration of CO2
+  co2_network: false
   cc_fraction: 0.9  # default fraction of CO2 captured with post-combustion capture
   hydrogen_underground_storage: true
   use_fischer_tropsch_waste_heat: true
diff --git a/scripts/prepare_sector_network.py b/scripts/prepare_sector_network.py
index fa485e6a..aca8d76f 100644
--- a/scripts/prepare_sector_network.py
+++ b/scripts/prepare_sector_network.py
@@ -277,6 +277,18 @@ def patch_electricity_network(n):
 
 def add_co2_tracking(n, options):
 
+    if options["co2_network"]:
+        nodes = pop_layout.index
+        co2_nodes = nodes + " co2 stored"
+        co2_locations = nodes
+        co2_vents = nodes + " co2 vent"
+        co2_max_sequestration = np.inf
+    else:
+        co2_nodes = "co2 stored"
+        co2_locations = "EU"
+        co2_vents = "co2 vent"
+        co2_max_sequestration = np.inf # TODO should be nodal sequestration potentials
+
     # minus sign because opposite to how fossil fuels used:
     # CH4 burning puts CH4 down, atmosphere up
     n.add("Carrier", "co2",
@@ -299,26 +311,33 @@ def add_co2_tracking(n, options):
     )
 
     # this tracks CO2 stored, e.g. underground
-    n.add("Bus",
-        "co2 stored",
-        location="EU",
+    n.madd("Bus",
+        co2_nodes,
+        location=co2_locations,
         carrier="co2 stored"
     )
 
-    n.add("Store",
-        "co2 stored",
+    n.madd("Store",
+        co2_nodes,
         e_nom_extendable=True,
-        e_nom_max=options['co2_sequestration_potential'] * 1e6,
+        e_nom_max=co2_max_sequestration, 
         capital_cost=options['co2_sequestration_cost'],
         carrier="co2 stored",
-        bus="co2 stored"
+        bus=co2_nodes
     )
 
+    # TODO if nodally resolved total allowed sequestration needs to
+    # be an extra_functionality constraint
+    # (best to implement it this way for either case)
+    # let e_nom_max represent geological potential
+    # don't forget to log duals of extra functionality!
+    # options['co2_sequestration_potential'] * 1e6
+
     if options['co2_vent']:
 
-        n.add("Link",
-            "co2 vent",
-            bus0="co2 stored",
+        n.madd("Link",
+            co2_vents,
+            bus0=co2_nodes,
             bus1="co2 atmosphere",
             carrier="co2 vent",
             efficiency=1.,
@@ -326,6 +345,25 @@ def add_co2_tracking(n, options):
         )
 
 
+def add_co2_network(n, costs):
+
+    # TODO create co2 network topology from electricity 
+    co2_links = pd.DataFrame()
+    
+    # assumed to be bidirectional
+    n.madd("Link",
+        co2_links.index,
+        bus0=co2_links.bus0.values + " co2 stored",
+        bus1=co2_links.bus1.values + " co2 stored",
+        p_min_pu=-1,
+        p_nom_extendable=True,
+        length=co2_links.length.values,
+        capital_cost=costs.at['CO2 pipeline', 'fixed'] * co2_links.length.values,
+        carrier="CO2 pipeline",
+        lifetime=costs.at['CO2 pipeline', 'lifetime']
+    )
+
+
 def add_dac(n, costs):
 
     heat_carriers = ["urban central heat", "services urban decentral heat"]