I did something "green" for my layout room.
I replaced all the track light bulbs with 650 lumen Natural Daylight
bulbs which are listed as saving $44 USD in energy cost per year.
6 X 44 = 264 USD to spend on model railroad stuff.
They are only 15W compared to 65W of previous ones.
I just happened to be in the light bulb section when a representative
of the local utility company was there promoting these bulbs which
were priced lower because of the company's support.
The downside is they were not made in the US.
However, neither is much of our model railroad stuff.