Geostrategic study of the evolution of energy harvesting systems based on the patent activity of flywheels and regenerative shock absorbers

This paper analyses the technological activity on energy harvesting and storage systems, such as flywheels and regenerative shock absorbers, for support of renewable energy and electric vehicle applications. The activity is analyzed based on the evolution of the patents over the last 20 years, based on databases such as Patbase and Derwnet. The data reveal that less than 50 % of the total flywheels patents and utility models are granted. China is identified as the leading innovator in this area, followed by the United States, Japan, and Germany, which collectively account for 84 % of all patent families. A ranking of related companies and institutes is dominated by Chinese companies such as CANDELA (SHENZHEN) TECHNOLOGY INNOVATION CO., SHENYANG WEIKONG NEW ENERGY TECH CO., followed by German and American companies such as LUK LAMELLEN, VYCON, Siemens, and Caterpillar Inc. The leading regions on regenerative shock absorbers technologies are Germany, China, USA, and the European Patent Office (EPO). The study shows a leadership of Germany accounting for 39 % of the priority patents. The study also identified the top 20 applicants with the highest number of patent families, which included European companies such as SCHAEFFLER AG, HYDAC, VOLKSWAGEN AG, and Continental Automotive GmbH.