Solar-Thermal Energy Conversion and Storage:Conductive Heat Transfer Using Self-Assembled Bulk Graphite

摘要

Consideration of technologies for the use of concentrated solar power (CSP) leads to the conclusion that there is substantially more energy in the sun's heat than there is in its light. At present, solar-thermal energy conversion and storage systems using CSP have the shortcomings of the use of high pressures and potential problems with corrosion. In the development of new materials and designs, two of the key issues of consideration are the: (a) thermal properties of the materials and (b) heat transfer within the system. Most current technologies utilise convective heat transfer of liquids but there are none that use conductive heat transfer with solid-state systems.The present work introduces such a system in the form of highly dense and aligned self-assembled graphite, which can be heated in air, provided the hot face temperature is at a temperature sufficiently low to avoid the onset of oxidation. Modelling of a small domestic-scale system, which has no competition in the marketplace, consisting of: (a) 4 m diameter concentrator, (b) block of graphite weighing ～160 kg, and (c) electricity generation system demonstrates that, in only 90 min and at ≤420°C, sufficient heat can be stored to supply 25% more than is required for a typical 24 h, domestic, electricity usage cycle.