an industrially feasible and effcient processing concept to produce PCM/polymer alloy with 70% PCM and more in the from of free flowing particles was also demonstrated. The PCM/Polymer alloy are possible to use with standard melt spinning grades of PLA, PET and PA and produce fibers fulfilling the requirements set by the final applications (texturing, dying, finishing, wash ability, health and safety aspects, cost etc.). PP was found not suitable for fiber production due to migration of PCM. In order to produce fibers with PCM/polymer alloy on standard industrial extrusion equipment it was found necessary to apply certain proprietary precautions. Suitable bio-based PCMs were identified and used in the project. How ever, a bio-based viscosity modified for the PCM was not found. This means that about 10-15% of the fiber weight will be from non-renewable sources (crude oil) in case of a PLA sheath polymer (bio-based sheath polymer).