diff --git a/dune/elasticity/materials/adolcmaterial.hh b/dune/elasticity/materials/adolcmaterial.hh
index 272ddc311af03250eec39dee79fcadbf1d96254f..f1e3e3f4a5e8d043f74b6a664db1148e56237877 100644
--- a/dune/elasticity/materials/adolcmaterial.hh
+++ b/dune/elasticity/materials/adolcmaterial.hh
@@ -68,7 +68,7 @@ public:
     }
 
     //! Evaluate the strain energy
-    ReturnType energy(std::shared_ptr<GridFunction> displace)
+    ReturnType energy(std::shared_ptr<GridFunction> displace) const
     {
         typename LocalEnergy::ReturnType aEnergy(0.0);