diff --git a/scripts/add_electricity.py b/scripts/add_electricity.py
index ad932cd8..ceef2390 100755
--- a/scripts/add_electricity.py
+++ b/scripts/add_electricity.py
@@ -94,7 +94,6 @@ import geopandas as gpd
 import powerplantmatching as pm
 from powerplantmatching.export import map_country_bus
 
-from vresutils.costdata import annuity
 from vresutils import transfer as vtransfer
 
 idx = pd.IndexSlice
@@ -105,6 +104,18 @@ logger = logging.getLogger(__name__)
 def normed(s): return s/s.sum()
 
 
+def calculate_annuity(n, r):
+    """Calculate the annuity factor for an asset with lifetime n years and
+    discount rate of r, e.g. annuity(20, 0.05) * 20 = 1.6"""
+
+    if isinstance(r, pd.Series):
+        return pd.Series(1/n, index=r.index).where(r == 0, r/(1. - 1./(1.+r)**n))
+    elif r > 0:
+        return r / (1. - 1./(1.+r)**n)
+    else:
+        return 1 / n
+
+
 def _add_missing_carriers_from_costs(n, costs, carriers):
     missing_carriers = pd.Index(carriers).difference(n.carriers.index)
     if missing_carriers.empty: return
@@ -138,7 +149,7 @@ def load_costs(tech_costs, config, elec_config, Nyears=1.):
                           "investment" : 0,
                           "lifetime" : 25})
 
-    costs["capital_cost"] = ((annuity(costs["lifetime"], costs["discount rate"]) +
+    costs["capital_cost"] = ((calculate_annuity(costs["lifetime"], costs["discount rate"]) +
                              costs["FOM"]/100.) *
                              costs["investment"] * Nyears)