These transactions are scheduled directly between a generator and a load, that is, bilateral - between two parties. All bilateral bids offered within NY are also automatically scheduled by NYISO.   This is energy brought into New York from neighboring control areas, which include PJM Interconnection, ISO New England, Hydro Quebec and IMO (Ontario). The amount scheduled is determined by price, thus not all that is bid gets scheduled. Energy flowing out of New York to the neighboring control areas. Again price determines how much energy is actually scheduled for export. This is the sum of energy imports less exports. Wheel throughs have no impact on this calculation as their flow in and out nets to zero. The amount of energy purchased in one control area and delivered to another control area, that is, just wheeling through New York. All generating units in New York must submit bids in order to be considered by NYISO. Units are scheduled based on economics and the need to maintain reliable system operation.    
Balancing Market Advisory Summary
Date: 01/24/2003

Offered MWh Scheduled MWh Percent
Bilateral Bids 4384 4384

Generation Bids 601762 452756 75.2%

Imports 63500 59352 93.5%
Exports 12797 12580 98.3%

Net Imports/(Exports) 50703 46772 92.2%
Wheel Throughs 7590 7513 99.0%