The "King's Speech" star along with his eco-campaigner partner were willing to install a large solar panel at their home in the posh Bedford Park suburb of the British capital, reported Femalefirst.
However, the planning officials have rejected their application saying the 51-year-old actors' property is located in an architectural conservation area.
"It would erode the architectural qualities of the listed host building itself and would cause actual harm to the character and appearance of the conservation area," Roger Shrimplin, the planning inspector, said.