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794 Articles

Australia’s Soft Plastic Recycling Debacle

December 15, 2022 by 80 Comments

We’ve all been told to cut back on waste to help prevent environmental crisis on Earth. Reducing waste helps reduce the need to spend time and energy digging up fresh materials, and helps reduce the amount of trash we have to go out and bury in the ground in landfills. Recycling is a big part of this drive, allowing us to divert waste by reprocessing it into fresh new materials.

Sadly, though, recycling isn’t always as magical as it seems. As Australia has just found out, it’s harder than it sounds, and often smoke and mirrors prevent the public from understanding what’s really going on. Here’s how soft plastic recycling went wrong Down Under.

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Singapore Branches Out Into Internet Of Trees

December 8, 2022 by 18 Comments

Five years ago, a 38-year-old woman was enjoying an outdoor concert with her family with one of her twin infants in her arms. In the week prior, it had been windy and rainy, but today, the weather was nice, and the concert was crowded. Without warning, a 270-year-old tembusu tree fell on the woman, pinning and ultimately killing her after the other concertgoers couldn’t remove it in time. This tragedy happened in spite of twice-yearly inspections where the tree showed no visual signs of trouble.

It’s exactly this type of incident that Singaporean officials hope to avoid by building an Internet of Trees. The equatorial island nation is home to roughly 5.5 million people, and around 7 million trees — about 6 million of which are tracked by Singapore’s National Parks Board, so that they can be managed remotely with an app. (The Board only tracks trees once they’ve reached a certain size, so we’ll assume that the other million are too young to join the fun just yet.)

While tree-triggered deaths are fairly few and far between, there are plenty of other ‘tree incidents’ that can occur, such as a branch falling, or a tree trunk snapping or uprooting. Depending on the size of the branch, this can be a dangerous nuisance as it could block roads, obscure signage, or destroy property. Thanks to the efforts of the National Parks Board, these incidents have dropped from around 3,000 per year at the turn of the millennium to under 500 per year today.

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Digital Taxidermy Spool Recycling concept art.

Spool Tower: Empty Filament Spool Or Base For Miniature Civilizations

December 2, 2022 by 23 Comments

While churning through rolls of FDM filament, there are these empty spools that remain at the end. These can be thrown out with the trash, or be used as a standard base for miniatures, for use with Dungeons & Dragons tabletop gaming or similar, or just as a display piece. The latter is what the blokes over at Digital Taxidermy ran with when they started their first Spool Tower Kickstarter campaign. Now they’re back with Spool Tower 2: The Re-Spoolening.

These are STL bundle packs that should contain all that’s needed to turn an empty filament spool into an art piece, minus of course the painting. To get a free taste of what the experience is like, Digital Taxidermy provides a few free STLs, such as for the Ye Olde Taxidermee Shoppee and the Hab Block from the new crowdfunding campaign.

This effort raises the interesting question of what other standard (plastic) shapes of packaging could conceivably be used in a similar manner. After all, why print the whole thing when half the model could be made from something you’d otherwise just toss into the trash bin?

Thanks to [scat happens] for the tip.

JCB Is Exploring Hydrogen Combustion Engines For Construction Machinery

November 30, 2022 by 60 Comments

When we think about greening up the planet, solar panels and electric cars are often at the forefront of our mind. However, there’s a whole bunch of other things out there that are spewing out carbon dioxide that also need to be cleaned up. That includes leaf blowers, lawn mowers, and yes – big equipment for construction and agricultural work!

JCB manufactures diesel engines for big machines, but is now looking to switch things up for a cleaner future. To that end, the company is working on hydrogen-burning engines for its big machines.

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Weird Energy Storage Solutions Could Help The Grid Go Renewable

November 29, 2022 by 122 Comments

We’re all familiar with batteries. Whether we’re talking about disposable AAs in the TV remote, or giant facilities full of rechargeable cells to store power for the grid, they’re a part of our daily lives and well understood.

However, new technologies for storing energy are on the horizon for grid storage purposes, and they’re very different from the regular batteries we’re used to. These technologies are key to making the most out of renewable energy sources like solar and wind power that aren’t available all the time. Let’s take a look at some of these ideas, and how they radically change what we think of as a “battery.”

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Better Air Quality Sensing With CO2

November 21, 2022 by 19 Comments

Measuring air quality, as anyone who has tried to tackle this problem can attest, is not as straightforward as it might seem. Even once the nebulous term “quality” is defined, most sensors use something as a proxy for overall air health. One common method is to use volatile organic compounds (VOCs) as this proxy but as [Larry Bank] found out, using these inside a home with a functional kitchen leads to a lot of inaccurate readings. In the search for a more reliable sensor, he built this project which uses CO2 to help gauge air quality.

Most of the reason that CO2 sensors aren’t used as air quality sensors is cost. They are much more expensive than VOC sensors, but [Larry] recently found one that was more affordable and decided to build this project around it. The prototype used an Arduino communicating over I2C to the sensor and an OLED screen, which he eventually put in a 3D printed case to carry around to sample CO2 concentration in various real-world locations. The final project uses a clever way of interfacing with the e-paper display that we featured earlier.

While CO2 concentration doesn’t tell the full story of air quality in a specific place, it does play a major role. [Larry] found concentrations as high as 3000 ppm in his home, which can cause a drop in cognitive function. He’s made some lifestyle changes as a result which he reports has had a beneficial impact. For human-occupied indoor spaces, CO2 can easily be the main contributor to poor air quality, and we’ve seen at least one other project to address this concern directly.

Making A Do-It-Yourself Sand Battery

November 21, 2022 by 96 Comments

Storing energy can be done in many ways, with the chemical storage method of a battery being one of the most common. Another option is a thermal battery, which basically means making something hot, and later extracting that heat again. In this video by [Robert Murray-Smith] the basic concept of a thermal battery that uses sand is demonstrated.

By running a current through a resistive wire that’s been buried inside a container with sand, the sand is heated up to about 200 °C. As [Robert] points out, the maximum temperature of the sand can be a 1000 °C or more. Because sand doesn’t boil like water, the total amount of energy stored in sand is correspondingly higher.

Extracting the thermal energy can be done rather inefficiently using the demonstrated Peltier element. A Stirling engine, or steam generator and turbine, would get a lot more energy out. Either way, the thermal battery itself is made using just plain sand, which makes it an attractive DIY target to tinker with.

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