diff --git a/pkgs/servers/home-assistant/custom-components/powercalc/package.nix b/pkgs/servers/home-assistant/custom-components/powercalc/package.nix
index e51cbf410e3a..b3b4fb99e2d4 100644
--- a/pkgs/servers/home-assistant/custom-components/powercalc/package.nix
+++ b/pkgs/servers/home-assistant/custom-components/powercalc/package.nix
@@ -2,6 +2,7 @@
   lib,
   buildHomeAssistantComponent,
   fetchFromGitHub,
+  fetchpatch,
 
   # dependencies
   numpy,
@@ -26,6 +27,14 @@ buildHomeAssistantComponent rec {
     hash = "sha256-Tm9h6ZHByuiM9XZz3D1TZR3ISbb16l0K1Vy8sJxI4+s=";
   };
 
+  patches = [
+    # Fix compatibility with Home-Assistant 2026.5.0
+    (fetchpatch {
+      url = "https://github.com/bramstroker/homeassistant-powercalc/commit/3d5e162954c21adfd9251c4d8e21872e66680454.patch";
+      hash = "sha256-7InjKxT8gPiR2IvLbA4oZpkgPRJbQY39SF4YNPilp4k=";
+    })
+  ];
+
   dependencies = [ numpy ];
 
   nativeCheckInputs = [