The New Electricity Trading Arrangements (Neta) introduced in March 2001 replaced the Electricity Pool with a fully competitive market where prices are determined by supply and demand.
Under Neta the majority of electricity trades are done through bilateral contracts ahead of time, but electricity can also be traded on future markets and through power exchanges. National Grid manages the balancing mechanism to ensure system security, but only about 2% of electricity is bought and sold by National Grid using this mechanism.
