Considerable research has been conducted on heat transfer enhancement of phase change materials (PCMs) in thermal energy storage systems. Heat transfer enhancement techniques such as the use of conductors like graphite, carbon fibre and carbon brushes have been proven to be effective. Shell and tube heat exchangers which utilise many tubes in the PCM have also shown to have good heat transfer performance. Fins embedded on tubes are also effective and very popular due to its simplicity. In this paper, a new concept of a heat transfer enhancement technique for a tube-in-tank phase change thermal energy storage system has been investigated, dynamic melting. This technique is used to improve the heat transfer during the melting process. It was found from experiments that dynamic melting was more effective than those without dynamic melting. The time taken to complete the phase change process was also found to be shorter when dynamic melting was utilised. It can be concluded from experiments that dynamic melting is an effective technique for enhancing heat transfer. (C) 2012 Elsevier Ltd. All rights reserved.