Trends in patents for solar thermal utilization in China

Since 2000, solar thermal utilization (STU) has a great process in China, not only with a large scale commercial development, but also with an increasing number of scientific publications and patent applications. In this paper, several representative technologies of STU in China are studied based on an analysis of the relationship between patents and policies. Patent information of STU is collected and analyzed in terms of the time distribution, type distribution and technical trends. The main driving factor—energy policy—was discussed through the patent analysis. STU patents took off after the millennium and 85.8% of them came from the solar water heater. For conventional technologies, 94.2% of the granted patents were from companies and individuals, and the patents proposed by various research institutions were mainly in the technological beginning and technological maturity. Advanced technologies are still at a growth stage in China, and they have 412 patents in all and 70.5% of the patents were from systematic design and test method. Energy policies have played a significant role in promoting the progress of STU in China. Based on a patent analysis, it can be expected that STU will enter the age of medium-high temperature in China.