150W ETFE Solar Panel

1. Why is the charging efficiency low when the product is used to recharge my devices?

A solar panel captures the sun’s energy and turns it into electricity. The intensity of solar radiation that a solar panel receives depends on a variety of factors, including season, time of day and cloud cover, etc. The product output power decreases when the solar radiation intensity becomes low. The output power and charging efficiency return to normal when the radiation intensity becomes normal.

2. Why is the actual power measured using a simple device lower than the nominal power?

The nominal maximum output (rated output) of a solar panel is measured under the STC (Standard Test Conditions, the world- recognized standard test conditions for ground mounted solar panels or modules). The “Standard Test Conditions” are defined as being 1000 W/m2 of irradiance when the cell temperature is 25°C with an air mass (AM) of 1.5. Besides, the test device must be at least BBB rated according to IEC 60904 (Letsolar uses AAA rated test device). If your test device does not meet this requirement, the results measured may vary greatly.

3. Why can't I recharge my electric appliances?

Ensure that your product is properly connected and used under normal sunlight conditions. If this error persists, use a voltmeter to measure the voltage at the output port. For safety reasons, connect the test instrument with the product before you expose the product to sunlight and start measuring.

4. Why does the output power drop significantly when there are bird droppings on the product?

This product is composed of multiple high efficiency solar cells connected in series. If shading is caused in one of the cells, for example, by leaves or bird droppings, it will inhibit the cell’s function to generate electricity. Moreover, this cell becomes a load consuming the power generated by other cells. As a result, the shadowed cell consumes a lot of power, thus causing hotspots or even burning the product in serious cases. Therefore, once shading in cells is discovered, immediately correct it.

5. Can I use this product to recharge portable power stations of other brands?

The voltage and current parameters of letsolar solar panels are optimized to match with the letsolar portable power stations to maximize their performance. Using this product to recharge the portable power stations of other brands may cause malfunctioning or damage to the product when the parameters do not match. If the parameters match, you can use the product to recharge the portable power stations of other brands. But letsolar does not guarantee that the performance can be maximized.