###### Abstract  
Continuous power supply for unmanned and automatic observation systems without suitable energy-storage capabilities in the polar regions is an urgent problem and challenge. However, few power-supply systems can stably operate over the long term in extreme environments, despite excellent performance under normal environments. In this study, a standalone hybrid wind-solar system is proposed, based on operation analysis of the observing system in the Arctic Ocean, the polar environments, and renewable-energy distribution in the polar regions. Energy-storage technology suitable for cold regions is introduced to support the standalone hybrid wind-solar system. Mathematical models of the power system at low temperature are also proposed. The low-temperature performance and characteristics of lead-acid battery are comprehensively elucidated, and a dedicated charging strategy is developed. A hybrid wind-solar charging circuit is developed using a solar charging circuit, a wind turbine charging circuit, a driver circuit, a detection circuit, an analog-to-digital converter (ADC) circuit, and an auxiliary circuit. The low temperature stability of charging circuit is test from \(-50\)\({}^{\circ}\)C to \(30\)\({}^{\circ}\)C. Temperature correction algorithm is designed to improve the efficiency of the power supply system. The power generation energy of the power system was simulated based on the monthly average renewable energy data of Zhongshan Station. A case study was applied to examine the technical feasibility of the power system in Antarctica. The five-month application results indicate that the power system based on renewable energy can maintain stable performance and provide sufficient power for the observing system in low ambient temperatures. Therefore, this power system is an ideal solution to achieve an environmentally friendly and reliable energy supply in the polar regions. hybrid wind-solar system; low-temperature energy storage; circuit design; application +
Footnote †: journal: Applied Softobservation of sea-ice thickness, snow depth, and sea-ice temperature profiles. For different depths of sea ice, the spectral intensity of solar radiation can be effectively measured using a fiber optic spectrometry system [8], and the design of the corresponding driver circuit was reported. All ice-based buoys are designed to achieve automatic and continuous observation of sea ice during annual cycles. However, very few buoys have achieved observation of sea ice for more than one year in the polar regions. The possible reasons for premature failure of buoys include: (1) decay of sea ice, (2) running out of power, (3) wild-animal damage, and (4) failure of the instrument itself. The robustness of observation equipment can be improved to protect against destruction by wildlife. In addition, the stability of the instrument has been greatly improved in recent years through continuous field tests and laboratory tests. In the Chinese National Arctic Research Expedition (CHINARE) from 2003 to 2017, the impact of premature sea-ice melting was overcome by locating the instruments in areas with suitable ice thickness and floe location [9; 10]. The power-supply problem is the most potential challenge for observation equipment used in the polar region to work for a long time. Due to the special geographical location of the Arctic Ocean and Antarctica, the design of the power system used in the polar regions has special demands. Burning fossil fuels in the polar regions causes environmental pollution and is therefore restricted. Thus, new demands for clean and sustainable energy such as wind, solar, hydro, and ocean energy have been created. In the polar regions, renewable energy systems (RESs) based on wind and solar energy are considered a clean, inexhaustible, and environmentally friendly method. Solar- and wind-energy resources usually have fluctuations; thus, a hybrid wind-solar system is developed to solve the problem of energy fluctuations in the polar regions.