Developing sustainable solar energy technology becomes extremely important to secure our energy future. A highly novel solar thermal technology, from both nanotechnology and phase change approaches, is proposed in this project to address the limitations associated with conventional solar thermal collectors. In this innovative technology, direct absorption nanoparticles are used to overcome the surface-controlled heat transfer limitation and absorb solar energy directly in the carrying fluid, and oscillating vapour bubbles (in oscillating heat pipes) are used to drive the fluids instead of pumps. Preliminary studies have shown the feasibility of the new concept, which has both prosperous scientific and applicaton propsects. Scientifically, it extends the direct absorption nanoparticles into a phase change domain, and practically it could promote the emergence of a new generation of solar collector. A systematic program is proposed in this project to address the challenges associated with the novel concept, which extends from suitable direct absorption nanofluid formulation, understanding the role of nanoparticles in the evaporation and condensation process, to its performance in ossillating heat pipes. The project is an ambitious, highly novel piece of work ideally suited to a Fellow with a strong background in solar energy and thermal science and engineering. The Fellow in question, Dr Lizhan Bai is perfectly (perhaps uniquely) suited to drive this project to success as he has independently designed, constructed and experimented with a number of challenging flow and heat transfer devices, especially heat pipe systems, and has outstanding analytical and mathematical modelling capability, which will contribute uniquely to the project. It will allow significant knowledge transfer into Europe, especially heat pipe systems, and create potentials long term collaborations and mutually beneficial co-operation between Europe and China.