 The purchasing agency is based in Newcastle upon Tyne.Since the introduction in 2001 of the New Electricity Trading Arrangements, electricity suppliers bid for the electricity and ROCs in competitive auctions held by the Non-Fossil Purchasing Agency, with any shortfall in price being funded by the Levy.As a result of these arrangements, the Non-Fossil Fuel Obligation has been generating a trading surplus, expected to have reached £500m by 2008.