Here is another device that can deliver you some savings which will address you lighting needs.
The Sunbeamer Skylight can deliver required daylight illumination when needed, directing sunlight where needed.
The Sunbeamer Skylight comes from SunCentral, a sun-tracking circular skylight which makes use of rotating mirrors to shoot lights deep within a building.
The Sunbeamer Skylight actually looks a lot like car grills, coming with fins which open and close as the whole assembly rotates. It features a GPS chip which tracks the sun and also enabling the motorized mirrors louver which would pinpoint the reflected light to any surface.