Specs (STC)
Standard Test Conditions (STC) are standard test conditions that reflect the operation of a solar panel under ideal conditions. As part of the tests, the weather of a clear sunny day with an air temperature of +25 °C, no wind, solar intensity of 1000 W/m² and an emission spectrum relative to air mass of 1.5 is simulated. The surface of the solar cell must be placed strictly perpendicular to the rays from the celestial body. Note that in real operation of the solar panel, such conditions are extremely rare. However, in general, the characteristics of the STC allow us to evaluate the "passport" parameters of the energy storage device.
Power (Pmax)
The amount of electricity in watts that a solar panel produces in one hour in tests using the STC method. The panel must provide the declared number of watts during normal operation.
Efficiency
Percentage of the maximum solar panel power to the incident radiation power produced. The efficiency parameter allows you to determine how efficiently the panel PV module converts solar energy into direct electric current.
USB A
"USB A" is the official name for the classic full-sized USB port.
Such connectors are very popular in computer technology, they are also standardly used in adapter chargers for 230 V household networks and 12 V auto sockets. In solar panels, mainly in a portable form factor,
USB A outputs are widely used for charging gadgets.
— Quantity. The number of full size USB ports in the solar panel design.
- The strength of the current. The maximum current output through the USB A connector to the device being charged. Note that different ports of the solar panels can output different current (for example, 1.5 A and 2.1 A). In this case, the highest current strength is usually indicated.
— Power. The maximum power in watts (W) that the solar panel is capable of delivering to one rechargeable gadget. High output power allows you to speed up the charging process. However, the appropriate power must be supported by the device being charged - otherwise the speed of the process will be limited by the characteristics of the gadget. For models with multiple USB A ports, the maximum power per device can be reached when the other ports are not used.
Waterproof
The level of protection is indicated by two digits according to the IP standard. The first digit indicates the protection against dust (maximum 6), the second indicates the degree of protection against water (maximum 8). The maximum degree of protection according to this standard is IP68, that is, complete tightness. There are also markings of the IPX4 type, where the first digit is not spelled out - this means that the solar panel has not been officially certified for dust resistance.
Dimensions
Dimensions of the solar panel in unfolded form.
Folded size
Dimensions of the solar panel when folded. First of all, the convenience of transportation depends on them. Knowing the dimensions, you can roughly estimate the amount of space needed to carry the solar panel in a backpack or when transporting it in the trunk of a car.