2026 Green Powered Challenge: Solar Powered Pi Hosts Websites In RAM

If you started with computers early enough, you’ll remember the importance of the RAMdisk concept: without a hard drive and with floppies slow and swapping constantly, everything had to live in RAM. That’s not done much these days, but [Quackieduckie]’s solar powered Pi Zero W web server has gone back to it to save its SD card.

Sustainability and low power is the name of the game. Starting with a Pi Zero W means low power is the default; a an SLS-printed aluminum case that doubles as the heat sink– while looking quite snazzy–saves power that would otherwise be used for cooling. The STLs are available through the project page if you like the look and have a hankering for passively cooled Pi. Even under load [Quackieduckie] reports temperatures of just 29.9°C,  less than a degree over idle.

The software stack is of course key to a server, and here he’s using Alpine Linux running in “diskless mode”– that’s the equivalent of what us oldsters would think of as the RAMdisk. That’s not that unusual for servers, but we don’t see it much on these pages. It’s a minimal setup to save processing, and thus electrical power, with only a handful of services kept running: lighttpd, a lightweight webserver, and duckiebox, a python-based file server, along with SSHD and dchron; together they consume 27 MB of RAM, leaving the rest of the 512 MB DDR2 the Pi comes with to quickly serve up websites without the overhead of SD card access.

As a webserver, [Quackieduckie] tested it with 50 simultaneous connections, which would be rather a lot for most small, personal web sites, and while it did slow down to an average 1.3s per response that’s perfectly usable and faster than we’d have expected from this hardware. While the actual power consumption figures aren’t given, we know from experience it’s not going to be drawing more than a watt or so. With a reasonably sized battery and solar cell– [Quackieduckie] suggests 20W–it should run until the cows come home.

This isn’t the first solar-powered web server we’ve seen, but this one was submitted for the 2026 Green Powered Challenge, which runs until April 24th.

Get Your Green Power On!

Nobody likes power cords, and batteries always need recharging or replacing. What if your device could run on only the power it could gather together by itself from the world around it? It would be almost like free energy, although without breaking the laws of physics.

Hackaday’s 2026 Green-Powered Challenge asks you to show us your devices, contraptions, and hacks that can run on the power they can harvest. Whether it’s heat, light, vibration, or any other source of energy that your device gathers to keep running, we’d like to see it.

The top three entries will receive $150 shopping sprees courtesy of the contest’s sponsor, DigiKey, so get your entry in before April 24, 2026, to be eligible to win.

Honorable Mentions

As always, we have several honorable mention categories to get your creative juices flowing:

  • Solar: In terms of self-powered anything, photovoltaic cells are probably the easiest way to go, but yet good light-harvesting designs aren’t exactly trivial either. Let’s see what you can run on just the sun. (Or even room lighting?)
  • Anything But PV: Harnessing the light is too easy for you, then? How about piezo-electric power or a heat generator? Show us your best self-powering projects that work even when it’s dark out.
  • Least Power: Maybe the smartest way to make your project run forever is to just cut down on the juice. If your project can run on its own primarily because of clever energy savings, it’s eligible for this mention.
  • Most Power: How much of a challenge is building a solar-powered desk calculator in 2026? How about pushing it to the other extreme? Let’s see how much power you can consume while still running without batteries or cords. Does your off-grid shack count here? Let’s see it!

Prior Art

We’ve seen a lot of green-powered projects on Hackaday over the years, ranging from a solar-powered web server to a microcontroller powered by a BPW34 photodiode. Will your entry run off the juice harvested by an LED? It’s not inconceivable!

Solar cells only work when the sun shines, though. As long as your body is putting out heat, this Seebeck-effect ring will keep on running. (Matrix vibes notwithstanding!) Or maybe you want to go straight from heat to motion with a Stirling engine. And our favorite environmental-energy-harvester of all has to be the Beverly Clock and its relatives, running on the daily heat cycles and atmospheric pressure changes.

Your Turn

So what’s your energy-harvesting project? Batteries are too easy. Take it to the next level! All you have to do to enter is put your project up on Hackaday.io, pull down the “Submit Project to…” widget on the right, and you’re in. It’s that easy, and we can’t wait to see what you are all up to.

And of course, stay tuned to Hackaday, as we pick from our favorites along the way.