Do you remember [Sam Smith]’s Metabolizer from a few years back? In case you’ve forgotten, this baby takes trash and turns it into printed plastic objects, and it’s solar-powered to boot. Although the Metabolizer didn’t win the 2018 Hackaday Prize, [Sam] and his machine won many achievements that year, including the Open Hardware Challenge. It’s fantastic to see the project still improving.

To recap, the sun hits the solar panels and charge up the battery bank. Once there’s enough power to start the reaction, it gets dumped into a heating element that turns biomass into biochar. This smoke is cooled, collected, refined, and fed into a small gas generator, which produces DC power to run a 3/4-horsepower shredder and the trash printer.

[Sam] likens this beast to a Rube Goldberg machine in that it performs an overly-complicated chain reaction to do a simple task. We certainly see his point, but we think that this machine is worth so much more than those classic machines, which tend to do nothing useful at all and tend to consume many resources in the process.  On the contrary, the Metabolizer’s chain reaction starts with sunshine and ends with useful objects that keep plastic out of landfills. Honestly, it’s more akin to a compost heap with a PhD in Biology and a handful of steroids and a 3D printer attached.

Unfortunately, [Sam] couldn’t get a prototype working in time for the Prize, and he turned to Patreon to gain support after the $1,000 ran out. Three years and a ton of improvements later, [Sam] has a working prototype that’s cheaper, more efficient, and easier to build. But can it be built relatively easily by someone other than [Sam]? Consider the gauntlet thrown down.

Not happy with your standard-style compost pile? You need a DIY trommel to sift out the bad stuff.