Simply install two lighting systems, and use the appropriate switches in summer or winter. Even better, automate the system so that the same switches will power the correct set of fixtures based on the outside temperature. (That makes it on topic for an automation news group.)
Now, for a question... I installed a 4 inch recessed light for an accent over a statue. I'd like to find an LED light that can screw into the fixture, and that has a focused light beam so that it will limit illumination to the statue. Ant suggestions?
-- Jim