A High-Power Density Triboelectric Nanogenerator for Harvesting Wave Energy

The global power by waves breaking around the coastlines worldwide has been estimated to be 2-3TW, and if wave energy is collected on open oceans, the global wave power is estimated to be one order of magnitude larger[1]. The water wave energy could turn out to be an even more benign source of power than wind, due to its abundance in the ocean [2]. Although it is a promising prospect for harvesting wave energy, most technologies for capturing wave power still remain in the testing phase. Currently, traditional devices usually harvest wave energy with complex hydraulic or mechanical structures and they drive an electromagnetic generator by transforming the energy from the water waves into rotary motion or linear reciprocal motion. However, these current oceans wave energy apparatuses exhibit unsatisfactory energy harvesting efficiency, high cost, and other methods of harvesting energy would have to be implemented [3-4]. In this work, a high-power density triboelectric nanogenerator (HPD-TENG) is designed and systematically investigated.This HPD-TENG is designed to be built by multiple units made of PTFE balls and 3D printed arc surface coated with melt adhesive reticulation nylon film. The integration of power generation model together with the kinetic model for the HPD-TENG is proposed and studied. The HPD-TENG can effectively transform arbitrary directional wave energy into electrical energy by utilizing charged balls rolling on optimized arc surface induced by ocean wave excitation. Furthermore, with the power generation units increases from 1 to 10 in one block, the power density increases linearly from 1.03 W/m 3 to 10.6 W/m 3 . This indicates that the power density of the HPD-TENG increases proportionally with the number of units connected in parallel without rectifiers due to its distinctive mechanism and structure. Hence the design of HPD-TENG can be regarded as an innovative and effective approach for large-scale blue energy harvesting through integrating more units to form HPD-TENG networks. References: Wang, Z. L. “Toward the blue energy dream by triboelectric nanogenerator networks,” Nano Energy 2017, 06.035 Tollefson, J. “Power from the Oceans: Blue Energy,” Nature 2014, 508, 302-304. Schiermeier, Q.; Tollefson, J.; Scully, T. “Electricity without Carbon,” Nature 2008, 454, 816-823. Zhang, S. L.; Xu, M.; Zhang, C.; Wang, Y.-C.; Zou, H.; He, X.; Wang, Z.; Wang, Z. L. “Rationally Designed Sea Snake Structure Based Triboelectric Nanogenerators for Effectively and Efficiently Harvesting Ocean Wave Energy with Minimized Water Screening Effect,” Nano Energy 2018, 48, 421-429