I have no idea how to do this. There is no electricity in the closet and I didn't find anything online.
^^^ Run extension cords or run some 12 gauge wire either in the attic or crawl space to your breaker panel and and in a breaker or two depending on if you run 12/2 or 12/3 wire in the closet you can then add in a couple of receptacles and a light... If it was me I'd run 12/3 that way you can run 2 circuits with half the work that way your less likely to overload the circut
For a closet op I'd get an LED, its perfect for small spaces, doesn't give off heat, and you can put it super close to your plants, which means closer internodes!! (Extension cord outta do lol) Check out my blog to see my operation!! http://forum.grasscity.com/blog/10101-randicalliburs-indoor-grow-lovers-blog/