The equivalence of gravitational potential and rechargeable battery for high-altitude long-endurance solar-powered aircraft on energy storage

• Published in: Energy conversion and management 2013-12, Vol.76, p.986-995
• Main Authors: Gao, Xian-Zhong, Hou, Zhong-Xi, Guo, Zheng, Fan, Rong-Fei, Chen, Xiao-Qian
• Format: Article
• Language: English
• Subjects: Altitude; Applied sciences; Direct energy conversion and energy accumulation; Durability; Electrical engineering. Electrical power engineering; Electrical power engineering; Electrochemical conversion: primary and secondary batteries, fuel cells; Endurance; Energy storage; Exact sciences and technology; Gravitational potential; High-altitude long-endurance; Rechargeable batteries; Rechargeable battery; Solar energy; Solar powered aircraft
• ISSN: 0196-8904; 1879-2227
• DOI: 10.1016/j.enconman.2013.08.023

•The scope of this paper is to apply solar energy to achieve the high-altitude long-endurance flight.•The equivalence of gravitational potential and rechargeable battery is discussed.•Four kinds of factors have been discussed to compare the two method of energy storage.•This work can provide some governing principles for the application of solar-powered aircraft. Applying solar energy is one of the most promising methods to achieve the aim of High-altitude Long-endurance (HALE) flight, and solar-powered aircraft is usually taken by the research groups to develop HALE aircraft. However, the crucial factor which constrains the solar-powered aircraft to achieve the aim of HALE is the problem how to fulfill the power requirement under weight constraint of rechargeable batteries. Motivated by the birds store energy from thermal by gaining height, the method of energy stored by gravitational potential for solar-powered aircraft have attracted great attentions in recent years. In order to make the method of energy stored in gravitational potential more practical in solar-powered aircraft, the equivalence of gravitational potential and rechargeable battery for aircraft on energy storage has been analyzed, and four kinds of factors are discussed in this paper: the duration of solar irradiation, the charging rate, the energy density of rechargeable battery and the initial altitude of aircraft. This work can provide some governing principles for the solar-powered aircraft to achieve the unlimited endurance flight, and the endurance performance of solar-powered aircraft may be greatly improved by the application of energy storage using gravitational potential.