diff --git a/config.default.yaml b/config.default.yaml
index 936dadea..186226b2 100644
--- a/config.default.yaml
+++ b/config.default.yaml
@@ -34,7 +34,14 @@ electricity:
     battery: 6
     H2: 168
 
-  conventional_carriers: [] # [nuclear, oil, OCGT, CCGT, coal, lignite, geothermal, biomass]
+  # estimate_renewable_capacities_from_capacity_stats:
+  #   # Wind is the Fueltype in ppm.data.Capacity_stats, onwind, offwind-{ac,dc} the carrier in PyPSA-Eur
+  #   Wind: [onwind, offwind-ac, offwind-dc]
+  #   Solar: [solar]
+
+  conventional_carriers: [] # nuclear, oil, OCGT, CCGT, coal, lignite, geothermal, biomass]
+  custom_powerplants: replace #replace or add
+  restrict_buildyear: 2015 #delete generators built after 2015
 
 atlite:
   nprocesses: 4
diff --git a/scripts/build_powerplants.py b/scripts/build_powerplants.py
index 38db8f9a..49229ad7 100644
--- a/scripts/build_powerplants.py
+++ b/scripts/build_powerplants.py
@@ -34,11 +34,39 @@ Description
 
 """
 
-import logging
+import logging, os
 from scipy.spatial import cKDTree as KDTree
 
 import pypsa
 import powerplantmatching as pm
+import pandas as pd
+
+logger = logging.getLogger(__name__)
+
+
+
+def add_custom_carriers(ppl):
+    switch = snakemake.config['electricity']['custom_powerplants']
+    if switch not in ('replace', 'add'):
+        logger.warning('custom_carriers is invalid keyword, try '
+                       '"replace" or "add"]. powerplants remain unchanged.')
+        return ppl
+    dirname = os.path.abspath(os.path.join(os.path.dirname(__file__),".."))
+    add_ppls = pd.read_csv(dirname + "/data/custom_powerplants.csv", index_col=0)
+    if switch == 'replace':
+        countries = add_ppls.Country.unique().tolist()
+        carriers = add_ppls.Fueltype.unique().tolist()
+        logger.info('replacing ' + str(carriers) + ' in ' + str(countries) + '...')
+        ppl.query('Fueltype != @carriers or Country != @countries',inplace=True)
+    logger.info('adding custom carriers...')
+    return ppl.append(add_ppls, sort='False')
+
+def restrict_buildyear(ppl):
+    year = snakemake.config['electricity']['restrict_buildyear']
+    logger.info('restricting build year of generators to ' + str(year) + '...')
+    ppl.YearCommissioned = ppl.YearCommissioned.fillna(0).astype(int) #in case of bad arrangement
+    ppl.YearCommissioned = ppl.YearCommissioned.astype(int)
+    ppl.query('YearCommissioned <= @year',inplace=True)
 
 if __name__ == "__main__":
     if 'snakemake' not in globals():
@@ -64,6 +92,10 @@ if __name__ == "__main__":
                              df.Technology.replace('Steam Turbine',
                                                    'OCGT').fillna('OCGT')))))
 
+    ppl = add_custom_carriers(ppl) # add carriers from own powerplant files
+    restrict_buildyear(ppl)
+
+
     cntries_without_ppl = [c for c in countries if c not in ppl.Country.unique()]
 
     substation_i = n.buses.query('substation_lv').index