The MOST Effective Thermal Mass Works Like A Sunburn

Way, way back in the days when men wore beards and wide-lapelled suits in exotic colors, only NASA had access to photovoltaics and ‘solar’ meant solar thermal. In those days of appropri…

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After Trucking Them Home, Old Solar Panels Keep On Trucking

The fact that there exist in our world flat rocks that make lightning when you point them at the sun is one of the most unappreciated bits of wizardry in this modern age. As hackers, we love all this of techno-wizardry-but some of us abhor paying full price for it. Like cars, one way to get a great discount is to buy used. [Backyard Solar Project] helped a friend analyze some 14-year-old panels to see just how they'd held up over the years, and it was actually better than we might have expected.

The big polycrystalline panels were rated at 235 W when new, and they got 6 of them for the low, low price of "get this junk off my property". Big panels are a bit of a pain to move, but that's still a great deal. Especially considering that after cleaning they averaged 180 W, a capacity factor of 77%. Before cleaning 14 years worth of accumulated grime cost about eight watts, on average, an argument for cleaning your panels. Under the same lighting conditions, the modern panel (rated to 200 W) was giving 82% of rated output.

That implies that after 14 years, the panels are still at about 94% of their original factory output, assuming the factory wasn't being overoptimistic about the numbers to begin with. Still, assuming you can trust the marketing, a half a percent power drop per year isn't too bad. It's also believable, since the US National Renewably Energy Laboratory (yes, they have one) has done tests that put that better than the average of 0.75 %/yr. Of course the average American solar panel lives in a hotter climate than [Backyard Solar Project], which helps explain the slower degradation.

Now, we're not your Dad or your accountant, so we're not going to tell you if used solar panels are worth the effort. On the one hand, they still work, but on the other hand, the density is quite a bit lower. Just look at that sleek, modern 200 W panel next to the old 235 W unit. If you're area-limited, you might want to spring for new, or at least the more energy-dense monocrystalline panels that have become standard the last 5 years or so, which aren't likely to be given away just yet. On the gripping hand, free is free, and most of us are much more constrained by budget than by area. If nothing else, you might have a fence to stick old panels against; the vertical orientation is surprisingly effective at higher latitudes.

#solarhacks #reuse #solarpanel #solarpower

Hard Lessons Learned While Building A Solar RC Plane

Although not the first to try and build a DIY solar-powered remote control airplane, [ProjectAir]’s recent attempt is the most significant one in recent memory. It follows [rctestflight]&#821…

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The Sunchronizer Keeps Your Solar Panel Aligned

In the past few years, the price-per-watt for solar panels has dropped dramatically. This has led to a number of downstream effects beyond simple cost savings. For example, many commercial solar fa…

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New Solar Spheres Claim To Be Better Than Solar Panels

When you think of solar energy, you probably think of flat plates on rooftops. A company called WAVJA wants you to think of spheres. The little spheres, ranging from one to four inches across, can …

Hackaday
Solar Energy Plant Creates Fuel

Normally, when you think of solar power, you think about photovoltaic cells or using the sun to generate steam. But engineers at Synhelion — a spin off from ETH Zurich — had a crazy ide…

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2024 Business Card Challenge: NoiseCard Judges The Sound Around You

Let’s face it: even with the rise of the electric car, the world is a noisy place. And it seems like it has only gotten worse in recent years. But how can we easily quantify the noise around …

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Garden Light Turned Mesh Network Node

We love a good deal, especially when it comes to scavenging parts for projects. Cheap outdoor solar lights are more than just garden accessories; they’re a handy source of waterproof enclosur…

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Sun On The Run: Diving Into Solar With A Mobile PV System

For obvious reasons, there has been a lot of interest in small-scale residential solar power systems lately. Even in my neck of the woods, where the sun doesn’t shine much from October to Apr…

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