I think I will continue to be a naughty boy and add part L to my list of sins.
Tut-tut!
If you care to look at the document mentioned by BAS the you can find it here.
http://www.planningportal.gov.uk/buildingregulations/approveddocuments/partl/approved
But I am not sure what law BAS believes you are contravening.
As I understood it, unless amendment state otherwise.
Fixed external lighting can be fitted if automatically controlled to switch off during daylight, switch off when not required(vague but when people are not detected) and have maximum lamp capacity of 150W or are energy efficient