It's a great question! We have tested dozens of portable solar panels from top brands sold in the US, and basically all of them suffer from the same problem--their output drops like a rock any time they are exposed to even a little bit of shade. Sometimes the drop can be as much as 90%!
And shade can come from anywhere--a small leaf could fall on the panel. You could set it up in full sun, but as the sun angle changes a small branch could block just a tiny corner of the panel. But our favorite source of shade? Grass!
If you look at the marketing photos from some of the top solar panel manufacturers, you will see lots of images that look like this:
Those panels are outputting almost zero power!
If you have a portable panel and a power station, you can easily replicate this. Just hook your panel up to your power station and keep an eye on the "watts in" on the screen of the power station. Set the panel on the grass, so small amounts of the panel are being shaded, just at the very bottom. Then lift the panel up so that shade is no longer blocking the bottom row--you will notice a giant leap!
Unless you have Shade Stopper panels. If you conduct this same test with Shade Stopper panels, the small amount of shade from the grass will cause just a small amount of power loss.
Here's a video of this experiment where you can see just how bad traditional panels are when just one cell gets blocked.
You might wonder--what about in full sun? Is there some loss that comes with the Shade Stopper technology when there is no shade? There is no loss! Shade Stopper panels can generate just as much power as a traditional panel in full sun. But apply even a little shade, and the Shade Stopper panel will drastically outperform the competition.
If you want maximum power from your panels, you need Shade Stopper solar panels.