Experimental Validation and Load-Supply Feasibility Assessment of a Battery-Coupled Wind–Photovoltaic Auxiliary Power System for a Small Marine Vessel

This study develops and experimentally validates a battery-coupled wind–photovoltaic power model for auxiliary electrical supply in small-vessel systems. The prototype integrates a 395 W CS6R-395MS monocrystalline photovoltaic module (CSI Solar Co., Ltd., Suzhou, Jiangsu, China), a 200 W FA200W horizontal-axis wind turbine (VEVOR, Rancho Cucamonga, CA, USA), maximum power point tracking (MPPT) power-conditioning stages, a 24 V/28 Ah AGM VRLA battery bank composed of four BAT212120086 batteries (Victron Energy B.V., Almere, The Netherlands), a 24 V DC bus, and a Phoenix 24/500 pure sine-wave inverter (Victron Energy B.V., Almere, The Netherlands), targeting non-propulsion navigation, communication, and lighting loads on a 5.7 m length overall (LOA) vessel. Field-acquired irradiance, cell temperature, incidence angle, PV voltage, wind speed, and rotor-speed data were used as time-dependent model inputs and compared with synchronized active-power measurements. Across the full 15–24 September 2025 experimental campaign, the maximum absolute relative error remained below 2.69%, while the aggregate statistical validation indices were ME = −0.1041 W, MAE = 0.3988 W, RMSE = 0.4931 W, and MAPE = 0.5946%. For the representative cloud-adverse case study conducted on 21 September 2025, the measured hybrid generation reached Ehyb=611.3 Wh over 8.28 h, corresponding to CRES=102.1% of the selected Eload=599 Wh/day auxiliary-load profile and to Chyb+bat=158.1% when the usable battery reserve at 50% depth of discharge (DOD) was included.