With the increasing attention to the excellent performance of triboelectric nanogenerators (TENG) in energy harvesting and sensing, various distributed energy harvesting and self-powered systems have sprung up. However, most TENGs are dedicated to the contact surface of the same curvature, while the research of its mechanism and application between surfaces of different curvatures are rarely explored. Herein, we propose a new curvature effect based TENG (C-TENG) through solid–liquid triboelectricity to harvest energy and electricity supply. The C-TENG can generate an open-circuit votage of 23.0 V and power of 0.12 μW with the periodic contact and separation between water and polytetrafluoroethylene (PTFE) by mechanical movement of a PTFE rod. Meanwhile, we also profoundly investigate some critical parameters of C-TENG such as various electrode lengths, PTFE rod displacements, tube diameters, concentrations and speeds. Moreover, the C-TENG can successfully harvest mechanical energy to light up 8 commercial LEDs or a standard calculator. And C-TENG can collect wave energy or monitor nearshore ocean conditions like wave heights and frequency through a wave-making system. Overall, Benefiting from its short-range displacement, C-TENG is proved to be a cost-effective and simple device for driving small electronics with good stability and durability and it can be further utilized in low-amplitude mechanical and wave energy collection.