After seeing Jons thread on adding lights to the layout, it got me motivated to do the same on mine. I always enjoyed the seeing the buildings all lite up when the sun goes down, especially as the days get shorter. It brings life to the layout when trains are parked for the night.
I used a power supply from a low voltage outdoor light system. I like using these because they have the sensors and timers. I can adjust how long and when to put the lights on. I strung low voltage wire throughout the layout. Then I used ceramic wedge based sockets that I tapped into the main low voltage wire. I didn’t do anything fancy inside the buildings. I just wanted some sort of light to shine inside. The lights were just stuck underneath each building or hung from the ceilings. My goal was to get a nice lantern glow since power did not exist in the backwoods. I tried LED bulbs but they gave off a clean white look to the buildings. I tried the 4W regular bulbs and they got me the look I wanted.
The the camera exaggerated the lights in the photos. I would say they are about half the brightness from what the camera shows.
At some point I would love to just get a lantern that lights up in the shelter. For now the bulb works and cant be seen unless you get down real low. In that case you will get a spruce tree where the sun don’t shine. Don’t ask how I know.