DIY Solar Generator Inspired By James Webb Telescope

May 30, 2025 by Lewin Day 23 Comments

If you look at this solar generator from [Concept Crafted Creations], you might think it’s somehow familiar. That’s because the design was visually inspired by the James Webb Space Telescope, or JWST. Ultimately, though, it’s purpose is quite different—it’s designed to use mirrors to collect and harness solar energy. It’s not quite there yet, but it’s an interesting exploration of an eye-catching solar thermal generator.

To get that JWST look, the build has 18 mirrors assembled on a 3D printed frame to approximate the shape of a larger parabolic reflector. The mirrors focus all the sunlight such that it winds up heating water passing through an aluminum plate. Each mirror was custom made using laser cut acrylic and mirror film. Each mirror’s position and angle can be adjusted delicately with screws and a nifty sprung setup, which is a whole lot simpler than the mechanism used on the real thing. The whole assembly is on a mount that allows it to track the movement of the sun to gain the most sunlight possible. There’s a giant laser-cut wooden gear on the bottom that allows rotation on a big Lazy Susan bearing, as well as a servo-driven tilting mechanism, with an Arduino using light dependent resistors to optimally aim the device.

It’s a cool-looking set up, but how does it compare with photovoltaics? Not so well. The mirror array was able to deliver around 1 kilowatt of heat into the water passing through the system, heating it to a temperature of approximately 44 C after half an hour. The water was warmed, but not to the point of boiling, and there’s no turbines or anything else hooked up to actually take that heat and turn it into electricity yet. Even if there were, it’s unlikely the system would reach the efficiency of a similarly-sized solar panel array. In any case, so far, the job is half done. As explained in the build video, it could benefit from some better mirrors and some structural improvements to help it survive the elements before it’s ready to make any real juice.

Ultimately, if you need solar power fast, your best bet is to buy a photovoltaic array. Still, solar thermal is a concept that has never quite died out.

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3D Filament lizards show decomposable joints

Sustainable 3D Prints With Decomposable Filaments

May 30, 2025 by Heidi Ulrich 22 Comments

What if you could design your 3D print to fall apart on purpose? That’s the curious promise of a new paper from CHI 2025, which brings a serious hacker vibe to the sustainability problem of multi-material 3D printing. Titled Enabling Recycling of Multi-Material 3D Printed Objects through Computational Design and Disassembly by Dissolution, it proposes a technique that lets complex prints disassemble themselves via water-soluble seams. Just a bit of H₂O is needed, no drills or pliers.

At its core, this method builds dissolvable interfaces between materials like PLA and TPU using water-soluble PVA. Their algorithm auto-generates jointed seams (think shrink-wrap meets mushroom pegs) that don’t interfere with the part’s function. Once printed, the object behaves like any ordinary 3D creation. But at end-of-life, a water bath breaks it down into clean, separable materials, ready for recycling. That gives 90% material recovery, and over 50% reduction in carbon emissions.

This is the research – call it a very, very well documented hack – we need more of. It’s climate-conscious and machine-savvy. If you’re into computational fabrication or environmental tinkering, it’s worth your time. Hats off to [Wen, Bae, and Rivera] for turning what might otherwise be considered a failure into a feature.

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Casting Shade On “Shade-Tolerant” Solar Panels

May 18, 2025 by Tyler August 32 Comments

Shade is the mortal enemy of solar panels; even a little shade can cause a disproportionate drop in power output. [Alex Beale] reviewed a “revolutionary” shade-tolerant panel by Renology in a video embedded below. The results are fascinating.

While shading large portions of the panels using cardboard to cut off rows of cells, or columns of cells, the shade tolerant panel does very well compared to the standard panel– but when natural, uneven shading is applied to the panel, very little difference is seen between the standard and active panels in [Alex]’s test. We suspect there must be some active components to keep power flowing around shaded cells in the Renology panel, allowing it to perform well in the cardboard tests. When the whole panel is partially shaded, there’s no routing around it, and it performs normally.

It’s hard to see a real-world case that would justify the extra cost, since most shading doesn’t come with perfect straight-line cutoffs. Especially considering the added cost for this “shade tolerant” technology (roughly double normal panels).

You might see a better boost by cooling your solar panels. Of course you can’t forget to optimize the output with MPPT. It’s possible that a better MPPT setup might have let the Renology panel shine in this video, but we’re not certain. Whatever panels you’re using, though, don’t forget to keep them clean.

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Electric Catamaran Sails High Seas Of Inland Canada

May 4, 2025 by Bryan Cockfield 4 Comments

There are a number of plans for DIY boats available online, so [Phil] went in search of one for a custom catamaran to travel the inland waterways of Canada. But none of the plans he found had options for electric motors so he modified one popular plan to include not only that, but plenty of other unique features as well throughout a long series of videos.

This isn’t [Phil]’s first electric boat, either. His first was a monohull with a long canopy above, providing shade for the occupants and a platform to mount solar panels. But that one was top heavy and unstable, so he pivoted to this catamaran design instead which has the perk of not only stability but a small draft. The plans were modified to use a similar propulsion system, though, but mounting the heavy panels on the roof of this boat was much less problematic. The roof itself retracts, and also includes some mosquito netting to enclose the cabin. He’s also added a head which is situated inside one of the hulls and has doors which fit into the retractable roof structure as well.

For navigating the peaceful inland waterways of Canada like the famous Rideau Canal, the Trent Severn Waterway which [Phil] frequents, or even quiet Ontario lake towns like Bobcaygeon we can’t imagine a better way to go that a peaceful, small electric boat like this one.

As summer rolls around in the northern hemisphere we’ll hope to see other solar electric boats like these out on the water, like this smaller electric-assisted kayak or this much larger solar electric houseboat.

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Comparing ‘AI’ For Basic Plant Care With Human Brown Thumbs

April 29, 2025 by Maya Posch 18 Comments

The future of healthy indoor plants, courtesy of AI. (Credit: [Liam])

Like so many of us, [Liam] has a big problem. Whether it’s the curse of Brown Thumbs or something else, those darn houseplants just keep dying despite guides always telling you how incredibly easy it is to keep them from wilting with a modicum of care each day, even without opting for succulents or cactuses. In a fit of despair [Liam] decided to pin his hopes on what we have come to accept as the Savior of Humankind, namely ‘AI’, which can stand for a lot of things, but it’s definitely really smart and can even generate pretty pictures, which is something that the average human can not. Hence it’s time to let an LLM do all the smart plant caring stuff with ‘PlantMom’.

Since LLMs so far don’t come with physical appendages by default, some hardware had to be plugged together to measure parameters like light, temperature and soil moisture. Add to this a grow light and a water pump and all that remained was to tell the LMM using an extensive prompt, containing Python code, what it should do (keep the the plant alive), and what Python methods are available. All that was left now was to let the Google’s Gemma 3 handle it.

To say that this resulted in a dramatic failure along with what reads like an emotional breakdown on the part of the LLM would be an understatement. The LLM insisted on turning the grow light on when it should be off and had the most erratic watering responses imaginable based on absolutely incorrect interpretations of the ADC data, flipping dry and wet. After this episode the poor chili plant’s soil was absolutely saturated and is still trying to dry out, while the ongoing LLM experiment, with an empty water tank, has the grow light blasting more often than a weed farm.

So far it seems like that the humble state machine’s job is still safe from being taken over by ‘AI’, and not even brown thumb folk can kill plants this efficiently.

Hydrogen Trains: Not The Success Germany Hoped They Would Be

April 29, 2025 by Jenny List 90 Comments

As transport infrastructure in Europe moves toward a zero-carbon future, there remain a number of railway lines which have not been electrified. The question of replacing their diesel traction with greener alternatives, and there are a few different options for a forward looking railway company to choose from. In Germany the Rhine-Main railway took delivery of a fleet of 27 Alstom hydrogen-powered multiple units for local passenger services, but as it turns out they have not been a success (German language, Google translation.). For anyone enthused as we are about alternative power, this bears some investigation.

It seems that this time the reliability of the units and the supply of spare parts was the issue, rather than the difficulty of fuel transport as seen in other failed hydrogen transport problems, but whatever the reason it seems we’re more often writing about hydrogen’s failures than its successes. We really want to believe in a hydrogen future in which ultra clean trains and busses zip around on hydrogen derived from wind power, but sadly that has never seemed so far away. Instead trains seem inevitably to be following cars, and more successful trials using battery units point the way towards their being the future.

We’re sure that more hydrogen transport projects will come and go before either the technological problems are overcome, or they fade away as impractical as the atmospheric railway. Meanwhile we’d suggest hydrogen transport as the example when making value judgements about technology.

Black and white photo of Evertop computer on desk

The Evertop: A Low-Power, Off-Grid Solar Gem

April 23, 2025 by Heidi Ulrich 32 Comments

When was the last time you saw a computer actually outlast your weekend trip – and then some? Enter the Evertop, a portable IBM XT emulator powered by an ESP32 that doesn’t just flirt with low power; it basically lives off the grid. Designed by [ericjenott], hacker with a love for old-school computing and survivalist flair, this machine emulates 1980s PCs, runs DOS, Windows 3.0, and even MINIX, and stays powered for hundreds of hours. It has a built-in solar panel and 20,000mAh of battery, basically making it an old-school dream in a new-school shell.

What makes this build truly outstanding – besides the specs – is how it survives with no access to external power. It sports a 5.83-inch e-ink display that consumes zilch when static, hardware switches to cut off unused peripherals (because why waste power on a serial port you’re not using?), and a solar panel that pulls 700mA in full sun. And you guessed it – yes, it can hibernate to disk and resume where you left off. The Evertop is a tribute to 1980s computing, and a serious tool to gain some traction at remote hacker camps.

For the full breakdown, the original post has everything from firmware details to hibernation circuitry. Whether you’re a retro purist or an off-grid prepper, the Evertop deserves a place on your bench. Check out [ericjenott]’s project on Github here.