Electric wholesale services

Several types of electric services are bought and sold in wholesale markets. These services include:

• Forward capacity: A commitment to provide a specified amount of supply (in MW) that is available for reliability purposes during a specified time period in the future. 
• Forward energy: A commitment to provide a specific amount of energy (in MWh) for a specific period of time two days or more following the day of the trade. 
• Day-ahead energy: A commitment to provide a specific amount of energy (in MWh) for a specified hour or number of hours on the day following the trade. 
• Real-time energy: Energy provided within an operating hour (in MWh) that was not contracted for in a day-ahead or forward transaction.
• Ancillary services: The services in addition to electric supply (in MW) that are required to deliver electricity to end users and to maintain system reliability. The type and terminology for ancillary services vary from region to region. Examples include automatic generation control (also known as frequency regulation), flexible ramp, spinning reserves, non-spinning reserves, replacement reserves voltage support, and black start.
• Transmission rights: Rights to move power (in MW) on a specific part of the transmission grid for a specific period in time. 
• Financial Transmission Rights (FTRs): Rights to receive financial compensation for congestion costs on a specific electric transmission path.
• Renewable energy credits (RECs): A commitment to provide a MWh of energy from a renewable resource.
• Emissions allowances: A right to emit a specified amount of a specific substance (i.e. SO₂, NO_x, or CO₂ equivalent) for a specified period of time (and in some cases within a specific geographic region). Allowances are initially allocated to parties by a regulator body, but then can be traded between parties. 
• Financial services: Various financial instruments used for risk management.