I've got a sneaky suspicion that you're being ripped off.
Here in .BE every energy contract can be cancelled (if you find a cheaper one for instance) without costs after 1 month.
Also if you initially signed up for 3 years or so.
I suspect they're buying cheap, tell you they're stuck on a long term (high price) contract and stuff +50% in their own pockets.
Which is not legal in .BE either: if you're selling energy to someone else with a profit, you need to be a registered energy company