NOVELTY - Heat transfer composition (I) comprises: pentafluoropropene (R-1225ye); and a refrigerant such as carbon dioxide (R-744), fluoromethane (R-41), difluoromethane (R-32), fluoroethane (R-161), 1,1,1-trifluoroethane (R-143a), 1,1,1,2-tetrafluoroethane (R-134a), 1,1,2,2-tetrafluoroethane (R-134), dimethyl ether, heptafluoroproane (R-227ea), propane (R-290), propene (R-1270), isobutane (R-600a), n-butane (R600), 2,3,3,3-tetrafluoropropene (R-1234yf), 1,1-difluorocyclopropane, 1,1,2-trifluorocyclopropane, 1,1,2,2-tetrafluorocyclopropane, pentafluorocyclopropane or ammonia.    USE - (I) is useful: for heating an article, and cleaning an article; for extracting a material from a particular solid matrix; for retrofitting a refrigeration device; in a mechanical power generation device; for extracting a substance from biomass; and in a heat transfer device and a blowing agent (claimed). (I) is useful for conventional refrigeration applications such as automobile air conditioning or as aerosol propellants or in vapor phase heating or cooling applications.    ADVANTAGE - (I) has a coefficient of performance within 10% of the fluid it is intended to replace, e.g. R-134a. (I) has a capacity greater than R-1225ye and/or R-1225yeE. (I) is non-azeotropic. (I) is non-flammable. (I) has a global warming potential of 150 or less (preferably 100 or less) (all claimed). (I) has improved capacity compared to R-1225ye alone.    DETAILED DESCRIPTION - INDEPENDENT CLAIMS are included for:    (1) a heat transfer device containing (I);    (2) a blowing agent comprising (I);    (3) a foamable composition comprising one or more components capable of forming foam and (I);    (4) a foam obtainable from the foamable composition;    (5) a sprayable composition comprising a material to be sprayed and a propellant comprising (I);    (6) a method for cooling an article comprising condensing (I) and evaporating (I) in the vicinity of the article to be cooled;    (7) a method for heating an article comprising condensing (I) in the vicinity of the article to be heated and evaporating the composition;    (8) a method for extracting a substance from biomass comprising contacting the biomass with a solvent comprising (I) and separating the substance from the solvent;    (9) a method of cleaning an article comprising contacting the article with a solvent comprising (I);    (10) a method for extracting a material from an aqueous solution comprising contacting the aqueous solution with a solvent comprising (I), and separating the substance from the solvent;    (11) a method for extracting a material from a particulate solid matrix comprising contacting the particulate solid matrix with a solvent comprising (I), and separating the substance from the solvent;    (12) a mechanical power generation device containing (I); and    (13) a method of retrofitting a refrigeration device comprising removing an existing heat transfer fluid, and introducing (I).