Bidding and clearing
The market accepts bids for each open timeslot continuously, and clears bids for each timeslot once per simulated hour. All cleared bids are priced at the clearing price, which is midway between the price of the last cleared supply bid and the price of the last cleared demand bid. In the figure, we see seven supply bids and nine demand bids, sorted by price. Each bid specifies both a price and a quantity, so the result is supply and demand curves, which may or may not intersect. In this example, supply bids s1-s6 are cleared, demand bids d1-d7 are cleared, and demand bid d8 is cleared for a partial quantity. These are the bids for which the asking price (for the supply bids) is lower than the corresponding offer price (the demand bids). The clearing price is the average price of the last supply bid s6 and the last demand bid d8. When the market clears, the accounts corresponding to the cleared bids are credited (for supply bids) or debited (for demand bids) at the clearing price, and the cleared quantities are added to the market (or depot) positions of the corresponding bidders.
After the market clears, unsatisfied bids (bids s7, d9, and the unsatisfied portion of d8) remain for consideration in the next clearing cycle, unless they are withdrawn by their respective bidders.
Each time the market clears, all bids, whether cleared or not, along with the clearing price, are made available to all Brokers, although the identies of the bidders are not revealed.