In the process of configuration throughout the solar system, first you need to make sure your electricity consumption of a day, then the collocation of the whole system can be calculated.
At 100w power output
(load), under the use of six hours a day, as example, to introduce the calculation method:
1.Should first calculate the daily consumption of hours (including loss of inverter) : If the inverter conversion efficiency is 90%, when the output power is 100 w, the actual demand of the output power should be 100 w / 90% = 111w, we use 6 hours everyday, so the power consumption is 111W*6 hrs =666Wh, that is 0.666 KWH
2.Calculate solar panels:
Calculated on effective sunshine time is 5 hours a day, and consider loss again. The output power of solar panels should be666Wh÷5h÷70% =190W. 70% means the loss coefficient
The power of solar panel/the voltage of solar panel=190W/18V=11.1A, can choose 15A controller