I can't see how this is going to work! The people who supply this fuel to the homeowner are private companies who's prices are controlled by the market. How can the state government swing a deal for cheaper fuel when it these companies who purchase this fuel months and months in advance?
Having worked for an oil company in a past life, I can see where this could damage things by causing a defacto "dumping" situation. Maine could lose small, independent oil dealers because of the price distortions caused by the Citgo oil.
The Maine government would be the broker, connecting the customer with the oil. As a broker, they can ask for a reduced price.