I used one of the earlier Energy Roms & absolutely loved it. But I found the battery drain too much for me (battery drain was exactly like the o.p. described). Reading through the posts on his rom, it was known that the battery life would suffer with such a fast rom. It was built for speed, not battery life. Alot of people in the forum would complain about it for some reason, but it looked to me like it worked as advertised. Energy made no claims on great battery life. I don't know if this has changed since his recent builds.
Since I wanted better battery life, I played with different Roms until I found Nightraven's winmo 6.5 1.9 worked best for me (I'm on an alltell touch pro). Was a good compromise on performance & battery life. Haven't tried his later releases because I am happy with my current install after much tweaking. Guess I'm not a flashaholic
You might have to do the same...try a few different roms until you are satisfied.