During holiday trips, if you take a lot of electronics with you, both a solar charger and a power bank can be useful. How do they differ from each other and which product is worth choosing?
Advantages of solar chargers:
Free Electricity - Solar chargers provide free energy from the sun. In addition, it is available all year round and you can easily supplement its shortage. A solar charger is a very permanent choice.
Environmentally friendly - electricity from solar energy is renewable. Using solar energy does not cause pollution or other negative environmental effects.
Disadvantages of solar chargers:
Bulky - to obtain a satisfactory result, the panels must be quite large. Don't go for small 2 to 5W panels. You'll just be disappointed that they charge your phone too slowly.
It needs sun - you won't be able to charge at night, and many cheaper variants won't be able to charge on cloudy days either. Many devices are sensitive to current fluctuations during charging. For example, iPhones may stop charging completely if the input current varies too much. This shouldn't be a problem with high-quality solar panel chargers as they often have a built-in charge controller.
How many watts does a solar charger need to charge my phone quickly?Theoretically 10 watts as you need 5 volts and 2 amps to charge your phone or tablet quickly. In fact, there is always some performance loss due to heat dissipation and resistance in the electronics. The important thing to pay attention to to check if the solar charger is fast is that it can produce 5 volts at 2 amps. High-quality solar panel chargers with a power of 15W or higher should be able to achieve this.
How long does it take to charge the phone with the solar charger?A typical solar panel labeled with an output voltage of 5 volts and 2 amps would charge an iPhone 7 (2000mAh) for an hour. For a panel labeled 5 volts and 1 ampere, it will take 2 hours.
Advantages of power banks:
Reliable - they don't require sunlight or anything else to run. As long as there is charge left in the power bank, you can charge your device.
Compact - powerbanks are light and small.
Disadvantages of power banks:
Limited number of charges - a fully charged high capacity power bank (around 10,000mAh) can typically charge the phone 3-5 times before it runs out.
Breakdown over time - All power banks lose stored energy, even when not in use. Some lose more than others. It doesn't matter if you look at the range of just a few weeks. The lost load during this period is too small to be noticed.
How long does it take to charge the phone with the power bank?A typical 5 volt 2 amp power bank would charge your iPhone 7 (2000 mAh) in an hour. For a powerbank marked with 5 volts and 1 amp, it will take 2 hours.
How much energy will I get from the power bank?You might think that a 20,000mAh battery 10 times would fully charge a 2,000mAh phone. This is not the case as charging is not 100% effective. The lower the amps a power bank uses to charge a device, the more energy is lost. Typical charging at 1 amp is 10% loss. Moreover, the fact that many manufacturers misleadingly label their powerbanks makes them even more distant from the correct number. Many are not labeled with the 5V power (which your phone or tablet needs), instead they denote the battery capacity at 3.7V. This gives only 74% of the capacity when charging with 5V. So labeled that way, a 20,000mAh power bank would only give 6.6 full charges, not 10.
Both power banks and solar chargers have their advantages and disadvantages. The best results will be achieved if you combine their power and supply both of them. Their alternate use depending on the circumstances will ensure that you will never run out of energy in your smartphone or other electronic device.