diff --git a/Snakefile b/Snakefile
index 639feab7..49685464 100644
--- a/Snakefile
+++ b/Snakefile
@@ -19,6 +19,8 @@ if not exists("config/config.yaml"):
 
 
 configfile: "config/config.yaml"
+configfile: "config/config.validation.yaml"
+configfile: "config/test/config.validation.yaml"
 
 
 COSTS = f"data/costs_{config['costs']['year']}.csv"
@@ -106,7 +108,7 @@ rule sync:
         cluster=f"{config['remote']['ssh']}:{config['remote']['path']}",
     shell:
         """
-        rsync -uvarh --no-g --ignore-missing-args --files-from=.sync-send . {params.cluster}
-        rsync -uvarh --no-g {params.cluster}/results results
-        rsync -uvarh --no-g {params.cluster}/logs logs
+        rsync -uvarh --ignore-missing-args --files-from=.sync-send . {params.cluster}
+        rsync -uvarh --no-g {params.cluster}/results results || echo "No results directory, skipping rsync"
+        rsync -uvarh --no-g {params.cluster}/logs logs || echo "No logs directory, skipping rsync"
         """
diff --git a/config/test/config.validation.yaml b/config/test/config.validation.yaml
index 7a043961..63259773 100644
--- a/config/test/config.validation.yaml
+++ b/config/test/config.validation.yaml
@@ -9,4 +9,9 @@ scenario:
   clusters:  # number of nodes in Europe, any integer between 37 (1 node per country-zone) and several hundred
   - 37
   opts: # only relevant for PyPSA-Eur
-  - 'Ept-12h'
+  - 'Ept'
+
+snapshots:
+  start: "2019-04-01"
+  end: "2019-04-10"
+  inclusive: 'left' # include start, not end
diff --git a/envs/environment.yaml b/envs/environment.yaml
index 9d800fdc..ceb1c13a 100644
--- a/envs/environment.yaml
+++ b/envs/environment.yaml
@@ -56,3 +56,4 @@ dependencies:
 
 - pip:
   - tsam>=1.1.0
+  - git+https://github.com/pypsa/pypsa.git
diff --git a/rules/common.smk b/rules/common.smk
index 8840c46e..c13e469e 100644
--- a/rules/common.smk
+++ b/rules/common.smk
@@ -16,7 +16,7 @@ def memory(w):
             factor *= int(m.group(1)) / 8760
             break
     if w.clusters.endswith("m") or w.clusters.endswith("c"):
-        return int(factor * (35000 + 600 * int(w.clusters[:-1])))
+        return int(factor * (55000 + 600 * int(w.clusters[:-1])))
     elif w.clusters == "all":
         return int(factor * (18000 + 180 * 4000))
     else:
diff --git a/rules/solve_electricity.smk b/rules/solve_electricity.smk
index 7233d378..757639f1 100644
--- a/rules/solve_electricity.smk
+++ b/rules/solve_electricity.smk
@@ -26,6 +26,7 @@ rule solve_network:
     threads: 4
     resources:
         mem_mb=memory,
+        walltime="24:00:00",
     shadow:
         "minimal"
     conda:
diff --git a/scripts/add_electricity.py b/scripts/add_electricity.py
index b4d31481..f5ddd01e 100755
--- a/scripts/add_electricity.py
+++ b/scripts/add_electricity.py
@@ -159,7 +159,7 @@ def sanitize_carriers(n, config):
 
     for c in n.iterate_components():
         if "carrier" in c.df:
-            add_missing_carriers(n, c.df)
+            add_missing_carriers(n, c.df.carrier)
 
     carrier_i = n.carriers.index
     nice_names = (
@@ -809,13 +809,10 @@ if __name__ == "__main__":
         unit_commitment = None
 
     if params.conventional["dynamic_fuel_price"]:
-        monthly_fuel_price = pd.read_csv(
-            snakemake.input.fuel_price, index_col=0, header=0
+        fuel_price = pd.read_csv(
+            snakemake.input.fuel_price, index_col=0, header=0, parse_dates=True
         )
-        monthly_fuel_price.index = pd.date_range(
-            start=n.snapshots[0], end=n.snapshots[-1], freq="MS"
-        )
-        fuel_price = monthly_fuel_price.reindex(n.snapshots).fillna(method="ffill")
+        fuel_price = fuel_price.reindex(n.snapshots).fillna(method="ffill")
     else:
         fuel_price = None
 
diff --git a/scripts/build_monthly_prices.py b/scripts/build_monthly_prices.py
index 7a61d933..495fd68e 100644
--- a/scripts/build_monthly_prices.py
+++ b/scripts/build_monthly_prices.py
@@ -52,14 +52,6 @@ from _helpers import configure_logging
 
 logger = logging.getLogger(__name__)
 
-validation_year = 2019
-
-# sheet names to pypsa syntax
-sheet_name_map = {
-    "5.1 Hard coal and lignite": "coal",
-    "5.2 Mineral oil": "oil",
-    "5.3.1 Natural gas - indices": "gas",
-}
 
 # keywords in datasheet
 keywords = {
@@ -69,6 +61,15 @@ keywords = {
     "gas": "GP09-062 Natural gas",
 }
 
+# sheet names to pypsa syntax
+sheet_name_map = {
+    "coal": "5.1 Hard coal and lignite",
+    "lignite": "5.1 Hard coal and lignite",
+    "oil": "5.2 Mineral oil",
+    "gas": "5.3.1 Natural gas - indices",
+}
+
+
 # import fuel price 2015 in Eur/MWh
 # source for coal, oil, gas, Agora, slide 24 [2]
 # source lignite, price for 2020, scaled by price index, ENTSO-E [3]
@@ -76,43 +77,30 @@ price_2015 = {"coal": 8.3, "oil": 30.6, "gas": 20.6, "lignite": 3.8}  # 2020 3.9
 
 
 def get_fuel_price():
-    fuel_price = pd.read_excel(
-        snakemake.input.fuel_price_raw, sheet_name=list(sheet_name_map.keys())
-    )
-    fuel_price = {
-        sheet_name_map[key]: value
-        for key, value in fuel_price.items()
-        if key in sheet_name_map
-    }
-    # lignite and hard coal are on the same sheet
-    fuel_price["lignite"] = fuel_price["coal"]
-
-    def extract_df(sheet, keyword):
-        # Create a DatetimeIndex for the first day of each month of a given year
-        month_list = pd.date_range(
-            start=f"{validation_year}-01-01", end=f"{validation_year}-12-01", freq="MS"
-        ).month
-        start = fuel_price[sheet].index[(fuel_price[sheet] == keyword).any(axis=1)]
-        df = fuel_price[sheet].loc[start[0] : start[0] + 18]
-        df = df.dropna(axis=0)
-        df.set_index(df.columns[0], inplace=True)
-        df.index = df.index.map(lambda x: int(x.replace(" ...", "")))
-        df = df.iloc[:, :12]
-        df.columns = month_list
-        return df
-
-    m_price = {}
+    price = {}
     for carrier, keyword in keywords.items():
-        df = extract_df(carrier, keyword).loc[validation_year]
-        m_price[carrier] = df.mul(price_2015[carrier] / 100)
+        sheet_name = sheet_name_map[carrier]
+        df = pd.read_excel(
+            snakemake.input.fuel_price_raw,
+            sheet_name=sheet_name,
+            index_col=0,
+            skiprows=6,
+            nrows=18,
+        )
+        df = df.dropna(axis=0).iloc[:, :12]
+        start, end = df.index[0], str(int(df.index[-1][:4]) + 1)
+        df = df.stack()
+        df.index = pd.date_range(start=start, end=end, freq="MS", inclusive="left")
+        df = df.mul(price_2015[carrier] / 100)
+        price[carrier] = df
 
-    pd.concat(m_price, axis=1).to_csv(snakemake.output.fuel_price)
+    return pd.concat(price, axis=1)
 
 
 def get_co2_price():
     # emission price
-    CO2_price = pd.read_excel(snakemake.input.co2_price_raw, index_col=1, header=5)
-    CO2_price["Auction Price €/tCO2"].to_csv(snakemake.output.co2_price)
+    co2_price = pd.read_excel(snakemake.input.co2_price_raw, index_col=1, header=5)
+    return co2_price["Auction Price €/tCO2"]
 
 
 if __name__ == "__main__":
@@ -123,5 +111,8 @@ if __name__ == "__main__":
 
     configure_logging(snakemake)
 
-    get_fuel_price()
-    get_co2_price()
+    fuel_price = get_fuel_price()
+    fuel_price.to_csv(snakemake.output.fuel_price)
+
+    co2_price = get_co2_price()
+    co2_price.to_csv(snakemake.output.co2_price)
diff --git a/scripts/cluster_network.py b/scripts/cluster_network.py
index e031fc7f..28d63278 100644
--- a/scripts/cluster_network.py
+++ b/scripts/cluster_network.py
@@ -506,15 +506,6 @@ if __name__ == "__main__":
             ).all() or x.isnull().all(), "The `potential` configuration option must agree for all renewable carriers, for now!"
             return v
 
-        # translate str entries of aggregation_strategies to pd.Series functions:
-        aggregation_strategies = {
-            p: {
-                k: getattr(pd.Series, v)
-                for k, v in params.aggregation_strategies[p].items()
-            }
-            for p in params.aggregation_strategies.keys()
-        }
-
         custom_busmap = params.custom_busmap
         if custom_busmap:
             custom_busmap = pd.read_csv(
diff --git a/scripts/simplify_network.py b/scripts/simplify_network.py
index b4c0829b..99964c65 100644
--- a/scripts/simplify_network.py
+++ b/scripts/simplify_network.py
@@ -534,15 +534,6 @@ if __name__ == "__main__":
     n = pypsa.Network(snakemake.input.network)
     Nyears = n.snapshot_weightings.objective.sum() / 8760
 
-    # translate str entries of aggregation_strategies to pd.Series functions:
-    aggregation_strategies = {
-        p: {
-            k: getattr(pd.Series, v)
-            for k, v in params.aggregation_strategies[p].items()
-        }
-        for p in params.aggregation_strategies.keys()
-    }
-
     n, trafo_map = simplify_network_to_380(n)
 
     technology_costs = load_costs(
@@ -560,7 +551,7 @@ if __name__ == "__main__":
         params.p_max_pu,
         params.simplify_network["exclude_carriers"],
         snakemake.output,
-        aggregation_strategies,
+        params.aggregation_strategies,
     )
 
     busmaps = [trafo_map, simplify_links_map]
@@ -573,12 +564,12 @@ if __name__ == "__main__":
             params.length_factor,
             params.simplify_network,
             snakemake.output,
-            aggregation_strategies=aggregation_strategies,
+            aggregation_strategies=params.aggregation_strategies,
         )
         busmaps.append(stub_map)
 
     if params.simplify_network["to_substations"]:
-        n, substation_map = aggregate_to_substations(n, aggregation_strategies)
+        n, substation_map = aggregate_to_substations(n, params.aggregation_strategies)
         busmaps.append(substation_map)
 
     # treatment of outliers (nodes without a profile for considered carrier):
@@ -592,7 +583,9 @@ if __name__ == "__main__":
             logger.info(
                 f"clustering preparation (hac): aggregating {len(buses_i)} buses of type {carrier}."
             )
-            n, busmap_hac = aggregate_to_substations(n, aggregation_strategies, buses_i)
+            n, busmap_hac = aggregate_to_substations(
+                n, params.aggregation_strategies, buses_i
+            )
             busmaps.append(busmap_hac)
 
     if snakemake.wildcards.simpl:
@@ -603,7 +596,7 @@ if __name__ == "__main__":
             solver_name,
             params.simplify_network["algorithm"],
             params.simplify_network["feature"],
-            aggregation_strategies,
+            params.aggregation_strategies,
         )
         busmaps.append(cluster_map)