I purchased my first home in March 2008 and a few months later Ontario Energy Savings (OES) came to my door offering to lock in my Gas and Electricity Rates. Reasons for this were because the rates were soon going up. After contemplating and pressure from the company (coupled with my inexperience as a new home owner), I signed the contract to flat rate my Natural gas and electricity (not water). Over the past few months I have seen a drastic increase in my bills (which I thought was having an extra member of the household move in). After closer look at my Electricity charges, Ontario Energy Savings charges a "OES Energy Charge" that has varied monthly from $50.63 to $55.69. Added onto the monthly charge of around $50.00 for "actual" electricity charges, I AM PAYING OVER DOUBLE what I should be paying for electricity.
The people from OES who came to my door and who I talked to on the phone NEVER mentioned of this add on.

I am currently getting more information on the subject and on OES. Searching OES online results in similar complaints.

My advice is, DO NOT let these companies sign you up unless you know exactly what you're getting into. Continue getting your utilities directly from the source (not from door to door companies). Avoid OES.