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Use solar energy as a complement of building heating energy, not only the building consumption will be reduced but also the air pollution problem during winter can be improved. However, the sparseness, discontinuity and instability of the solar energy are bottleneck of solar energy utilization technology. Thus the thermal storage technology becomes the most important part in solar energy system. Phase change thermal storage technology is more efficient then water, and it can charge the surplus solar energy for cloudy days to improve the utilization rate of solar energy. The performance of solar system can be improved by using phase change material storage technology. This review summarizes the previous study on phase change materials storage in solar energy application; the content of this paper can provide a reference for relative studies.

Most of the existing ID-based designated verifier proxy signature schemes are implemented with pairings. The computation of parings is still much more expensive than the common modular multiplications and exponentiations. To obtain better efficiency, we construct an efficient ID-based DVPS scheme without pairings. The scheme is designed based on the hardness of the discrete logarithm problems. It is proven secure against adaptively chosen message attacks, in the random oracle model.

Urumqi locates in Xinjiang province, which belongs to cold climate zone in China, the local heating period during the winter up to 6 months. The local solar energy is abundant; up to 130-140 Kcal/cm2·Y that can provides advantage condition for utilization of solar energy. Floor radiant heating system requires lower supply temperature compared with the traditional heating system, which provides an advantage condition for using solar energy as heat source since it is already widely used in Urumqi. Based on these, the study established a solar energy floor heating system in XinJiang University. The system’s components, operating principle and indoor air temperature profile had been introduced in this paper. Through the experimental study the research results shows that 40% time of winter period in cold climate zone, the solar energy floor system can working well without any auxiliary heat source, the heat generate from solar collect system can satisfied the indoor heating requirement. The application of this system can make energy saving and environmental protection become true.