The pilot took off from Blackbushe to position the aircraft to Turweston for maintenance. During the climb-out, whilst retracting the landing gear, the aircraft lost electrical power. The pilot was unable to restore power and elected to return to Blackbushe. He then found that the landing gear could not be lowered manually and so he decided, as originally planned, to fly to Turweston where the aircraft’s maintenance organisation was based. The aircraft made a gear-up landing at Turweston and the pilot, who was uninjured, exited the aircraft normally.