You also get a power and green bar for every certain amount of posts you make. When I first joined here, when I hit 50 posts, I got 1 power and 1 bar. Then it doubled to every 150 posts, then to 250 and finally to every 500 posts. When I hit 5,000 posts, my rep point level doubled to every 200 points before I could receive another green bar, although I still received a power for every 100 points. The amount of posts you have to make to receive a power varies for everyone.