Conventional solar photovoltaic systems employ silicon-based photovoltaic (PV) cells arranged in arrays on rigid panels that are mounted on a fixed structure, such as the roof of a building. However, there are many field applications where it is desirable to have a solar PV array that is portable and lightweight so that it can be carried by a person and used on treks in remote or mountainous areas, in temporary camps or relief zones, in military field deployments, etc.
Single PV cells or small solar PV arrays have been used to power some types of small, portable electrical devices such as calculators, flashlights, lanterns, mobile phones, etc., but can provide only a low voltage (open circuit) output of about 0.6 volt and maximum power output in the 0.5 to 5 watt range. Medium power intensity applications, such as for powering field computer equipment, premises heating or cooling equipment, satellite and microwave communications equipment, lighting, pumps, hand tools and other field machinery, etc., require a higher level of voltage (open circuit) output in the 12 to 24 volts range and maximum power output in the 100 to 200 watt range. For comparison, a conventional fixed-mount (rooftop) solar PV array using crystalline silicon cells having a solar conversion efficiency of about 14% can provide a voltage (open circuit) output of up to 33 volts and maximum power output of about 200 watts for a panel of about 5 ft×3.2 ft (1.5 sq-m) size that weighs about 37 pounds (17 kg). This size and weight would be too large and heavy for one person to carry on foot comfortably.
Therefore, for medium power intensity uses in remote areas, it would be desirable to provide a solar PV module that is portable enough to be carried by one person on foot, along with that person's other required field equipment. Further, It would desirable that such a personal PV module can be easily disconnected, transferred and quickly re-installed to a new location by one person.