ENERGY EFFICIENCY: IEA to help countries improve management of 'hidden fuel' Henry Gass, E&E reporter Published: Tuesday, May 20, 2014 The 'hidden fuel' is the fuel you don't use, and it can be very hard to keep track of. Please subscribe to ClimateWire to read the full story. Username: Password: Forgot your access codes? Recover them. Not a subscriber? Sign up for a trial. Ready to subscribe? Click here.