In an era when we're carrying more and more technology with us no matter where we go, it's important to keep all your devices charged, even when you're camping. We put the top 100-watt-and-larger solar panels through head-to-head testing to find out which are the most efficient in direct and indirect light, which are the most portable, and which are the easiest to operate. We divided our testing into four metrics: direct solar charging speed, indirect solar charging speed, portability, and functionality.
Direct Solar Charging Speed
We set up every solar panel in the same open area with full sun exposure to test their direct solar charging speed. We then hooked up every solar panel to an identical battery with a 20% charge. We then left each panel to charge its test battery to 80% to see how long it took.
In a subsequent test, we left every panel to charge their test battery for one hour. These side-by-side tests ensure that every panel is experiencing the same conditions, making the results easy to compare and interpret.
We also hooked up a voltmeter directly to the output lines of each panel to measure their output at peak sunlight efficiency. We recorded our results and compared them with the manufacturer's claimed output.
Indirect Solar Charging Speed
To measure indirect solar charging speed, we repeated the direct solar charging speed test with a large white sheet suspended above the solar panels to simulate a cloudy day. With this simulated cloud cover in place, we then repeated the same tests from our direct solar charging speed metric to see how much energy and power each panel puts out.
Portability
To test portability, we measured the weight and dimensions of every solar panel. We measured them when folded and set up. We also carried them around, packed them in our cars, and set up every panel to evaluate their functional portability.
Functionality
To test functionality, we assessed the features that make each panel more or less easy to use. We assessed how many devices each panel could charge, whether it had features to angle the panel towards the sun, if it came with all necessary cables, and other relevant aspects that contribute to functionality.
