Sierra Trading Post Explores: How Do Solar Panels Work?

Technological advancements are continuously making solar panels smaller, thinner and more affordable, and in turn allowing outdoor enthusiasts to harness the power of the sun to make their time away from home safer and more convenient.

Solar panel kits, like those offered by Brunton, offer portable solar panels ideal for campers, RVs and remote cabins. Some backpackers and hikers even pack small, portable solar chargers to make sure they have a charging source in case of an emergency.

I've always been a big fan of solar power, but I've never completely understood how it works. So, I'm using this installment of Sierra Trading Post Explores to figure it all out.

What are solar panels made of?

Solar panels are made of a bunch of little energy-gathering units called photovoltaic cells. The photovoltaic cells are like super-thin sandwiches, with anti-reflective glass covers on the outside, then metal contact points, and finally two charged silicon layers in between. The metal contact points complete the circuit and allow electricity to move to wires.

solar panels

How do solar panels work?

Remember the two "charged" silicon layers in the middle of the super-thin photovoltaic cell sandwiches? Those are the key to turning sunlight into electricity. The two silicon layers have been specially treated to be charged, or "unstable," in terms of their electrons. A steady flow of electrons creates energy, and the instability of the two silicon layers is the first step to creating that flow.

Let's focus on these charged silicon layers to get a better understanding of how this works. The top layer of silicon is treated with phosphorus to add extra electrons (and a negative charge), and becomes the "N-type" silicon layer. The bottom layer is treated with boron to result in fewer electrons (and a positive charge), and becomes the "P-type" silicon layer.

This means that the N-type layer has too many electrons and is desperate to lose one, while the P-type layer has too few electrons and is desperate to gain one. All the N-type layer needs to share its extra electron with the bottom P-type layer is a photon of sunlight to push it free.

How is sunlight transformed into electricity?

solar panels Flickr photo courtesy Nasa Goddard Space Flight Center.

When the photons of sunlight hit the photovoltaic cells in a solar panel, they "excite" the electrons in the N-type silicon layer, encouraging them to move down to the P-type layer. This movement creates the flow of electrons that is electricity.

solar panels

The flow of electricity that's kicked off by the sunlight then flows through the metal contacts to wires that transport the electricity, completing the electric circuit. However, before the electricity generated by the solar panel can be used, it must be converted from DC (direct current) to AC (alternating current), so it runs through an inverter, and is finally ready to power electronics of all shapes and sizes.

Use solar panels to power your outdoor adventure

Now that you know how solar panels work, are you ready to power your next adventure with the sun? A lot of people like to have a solar-powered energy source in the backcountry or at their campsite to power a GPS or cell phone. Whether you're vacationing in an off-grid cabin, spending a full day on the boat or exploring the country in an RV or camper, portable solar panels are an efficient, convenient way to keep electronics charged and working.

That wraps up this installment of Sierra Trading Post Explores. I hope you learned a thing or two. Join me next month for another look into the lesser known aspects of your outdoor adventures and gear!
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