See minimum price system.

In an energy derivatives contract, the settlement price of the contract based on a particular location or particular blend of the commodity.

an internal price that consumers are believed to use to compare actual prices

in an energy derivatives contract, the market price reference based on a particular location or specified grade or blend of the commodity, which is used for settlement of the contract.

The price of future contract used as "reference" e.g., for determining an opening price, starting an algorithm, or figuring into an index; is usually the settlement price or last closing price.