Tree Planting Festivals, Air Cannons, Self-Burying Seeds, And The Complexities Of Reforestation

June 8, 2023 by Maya Posch 20 Comments

At first glance the problem of how to plant trees would seem to be a straightforward one: take a seed, jam it into the soil and let nature take its course. Or alternatively do much the same with a sapling that already got a start in a nice, comfortable greenhouse before leaving it to its own devices. To the average person this is generally the point where it’s considered a ‘done deal’, but one only has to take a look at the average survival rate of saplings out in the wild to perish that thought.

Each environment offers its own set of challenges when it comes to reforestation, which can perhaps be considered ironic as many of these trees are being planted where forests used to be, albeit centuries ago in many cases. There are the easy spots, such as flat fields, with rich soil, ample rain and mild weather, to the challenging terrain of Iceland, or mountainous terrain. Here the logistics are challenging and where once rich forests flourished, the very landscape seems adamant to reject this botanic intrusion.

Further complicating matters here are the myriad of reasons why we’re looking at planting so many new trees that it has even become an internet thing, as with the 2019 ‘Team Trees’ 20 million new trees challenge. So how did we get here, why exactly are we doing all of this, and how much of these attempts do bear fruit?

Continue reading “Tree Planting Festivals, Air Cannons, Self-Burying Seeds, And The Complexities Of Reforestation” →

A Fresnel Lens Without The Pain

June 3, 2023 by Jenny List 21 Comments

Making a traditional glass lens requires a lot of experience, skill, and patience grinding a piece of glass to the required shape, and is not for the casual experimenter. Making a glass Fresnel lens with its concentric rings requires even more work, but as the ever-resourceful [Robert Murray-Smith] shows us, a Fresnel lens can be made from far more mundane materials. He shows us a working lens made from transparent plastic tube, and even successfully smoulders a piece of paper with it under the anaemic British sun.

His lens, with its circular profile tube filled with water, is not perhaps the most efficient lens in terms of light focused per unit area of lens. From dredging up our highschool physics lessons we are guessing that half the light is diffracted outwards rather than inwards by the cylindrical profile of the coil, but for the cost of the whole device we’re not sure that matters. Next time we’re shipwrecked on a desolate island with a handy supply of clear plastic tube and fresh water, we know we can always raise a fire.

If Fresnel lenses interest you, we’ve taken a look in the past at their history.

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Hackaday Prize 2023: This Challenge Makes It So Easy Being Green

May 31, 2023 by Elliot Williams 2 Comments

This year’s Hackaday Prize is our first nice round number – number ten! We thought it would be great to look back on the history of the Prize and cherry-pick our favorite themes from the past. Last year’s entire theme was sustainable hacking, and we challenged you to come up with ways to generate or save power, keep existing gear out of the landfill, find clever ways to encourage recycling or build devices to monitor the environment and keep communities safer during weather disasters, and you all came through. Now we’re asking you to do it again.

There are hundreds of ways that we can all go a little bit lighter on this planet, and our Green Hacks Challenge encourages you to make them real. Whether you want to focus on clean energy, smarter recycling, preventing waste, or even cleaning up the messes that we leave behind, every drop of oil left unburned or gadget kept out of the landfill helps keep our world running a little cleaner. Here’s your chance to hack for the planet.

Inspiration

One thing we really loved about last year’s Green Hacks was that it encouraged people to think outside the box. For instance, we got some solar power projects as you’d expect, but we also got a few really interesting wind power entries, ranging from the superbly polished 3D Printed Portable Wind Turbine that won the Grand Prize to the experimental kite turbine in Energy Independence While Travelling, to say nothing of the offbeat research project toward making a Moss Microbial Fuel Cell.

3D Printed Portable Wind Turbine

Moss Microbial Fuel Cell

Energy Independence While Travelling

Plastic was also in the air last year, as we saw a number of projects to reuse and recycle this abundant element of our waste stream. From a Plastic Scanner that uses simple spectroscopy to determine what type of plastic you’re looking at, to filament recyclers and trash-based 3D printers to make use of shredded plastic chips.

Polyformer

The Trash Printer – Version 3

Plastic Scanner

Finally, you all really put the science into citizen science with projects like OpenDendrometer that helps monitor a single tree’s health, and the Crop Water Stress Sensor that does the same for a whole field. Bees didn’t get left out of the data collection party either, with the Beehive Monitoring and Tracking project. And [Andrew Thaler]’s tremendously practical Ocean Sensing for Everyone: The OpenCTD brought the basics of oceanic environmental monitoring down to an affordable level.

OpenDendrometer

Crop Water Stress Sensor

Beehive Monitoring and Tracking

Ocean Sensing for Everyone: The OpenCTD

Now It’s Your Turn to be Green

If any of the above resonates with your project goals, it’s time to put them into action! Start up a new project over on Hackaday.io, enter it into the Prize, and you’re on your way. Ten finalists will receive $500 and be eligible to win the Grand Prizes ranging from $5,000 to $50,000. But you’ve only got until Tuesday, July 4th to enter, so don’t sleep.

As always, we’d like to thank our sponsors in the Hackaday Prize, Supplyframe and DigiKey, but we’d also like to thank Protolabs for sponsoring the Green Hacks challenge specifically, and for donating a $5,000 manufacturing grant for one finalist. Maybe that could be you?

Vehicle-to-Grid Made Easy

May 25, 2023 by Bryan Cockfield 37 Comments

As electric cars continue to see increased adoption, one associated technology that was touted long ago that still hasn’t seen widespread adoption is vehicle-to-grid or vehicle-to-home. Since most cars are parked most of the time, this would allow the cars to perform load-levelling for the grid or even act as emergency generators on an individual basis when needed. While this hasn’t panned out for a variety of reasons, it is still possible to use an EV battery for use off-grid or as part of a grid tie solar system, and now you can do it without needing to disassemble the battery packs at all.

Normally when attempting to use a scrapped EV battery for another use, the cells would be removed from the OEM pack and reorganized to a specific voltage. This build, however, eliminates the need to modify the packs at all. A LilyGO ESP32 is used to convert the CAN bus messages from the battery pack to the Modbus communications protocol used by the inverters, in this case a Fronius Gen24, so the inverter and battery can coordinate energy delivery from one to the other automatically. With the hard part out of the way, the only other requirements are to connect a high voltage DC cable from the battery pack to the inverter.

[Dala], the creator of this project, has taken other steps to ensure safety as well that we’d recommend anyone attempting to recreate this build pays close attention to, as these battery packs contain an extremely large amount of energy. The system itself supports battery packs from Nissan Leafs as well as the Tesla Model 3, which can usually be found for comparably low prices. Building battery energy storage systems to make up for the lack of commercially-available vehicle-to-home systems isn’t the only use for an old EV battery, though. For example, it’s possible to use Leaf batteries to triple the range of other EVs like [Muxsan] did with this Nissan van.

Continue reading “Vehicle-to-Grid Made Easy” →

A pinwheel sits in an aquarium to simulate an offshore wind turbine. Bubbles come up from the "seabed" to encircle it to demonstrate a bubble curtain with an image of a sound waveform overlaid with the video to show the sound confined to the area within the bubble curtain.

Keeping The Noise Down Under The Sea

May 23, 2023 by Navarre Bartz 13 Comments

Since sound is the primary sense used by most ocean life, disruptions to the natural noise levels in the ocean from human activities can be particularly problematic for marine life. [DW Planet A] has a video describing some of the ways we can mitigate these disruptions to our friends under the sea.

Being noisy neighbors isn’t just a problem for whales but for everything down to the plankton at the base of the food web. Underwater construction like offshore wind installations get flak for being noisy, but technologies like bubble curtains can reduce noise output by up to 90% to the surrounding waters while still getting those nice low carbon energy benefits that prevent further ocean acidification and warming. Continue reading “Keeping The Noise Down Under The Sea” →

Passively Generating Power Day And Night Takes The Right Parts

May 13, 2023 by Donald Papp 18 Comments

A thermoelectric generator (TEG) can turn a temperature difference into electricity, and while temperature differentials abound in our environment, it’s been difficult to harness them into practical and stable sources of power. But researchers in China have succeeded in creating a TEG that can passively and continuously generate power, even across shifting environmental conditions. It’s not a lot of power, but that it’s continuous is significant, and it could be enough for remote sensors or similar devices.

Historically, passive TEGs have used ambient air as the “hot” side and some form of high-emissivity heat sink — usually involving exotic materials and processes — as the “cold” side. These devices work, but fail to reliably produce uninterrupted voltage because shifting environmental conditions have too great of an effect on how well the radiative cooling emitter (RCE) can function.

The black disk (UBSA) heats the bottom while the grey square (RCE) radiates heat away, ensuring a workable temperature differential across a variety of conditions.

Here is what has changed: since a TEG works on temperature difference between the hot and cold sides, researchers improved performance by attaching an ultra-broadband solar absorber (UBSA) to the hot side, and an RCE to the cold side. The UBSA is very good at absorbing radiation (like sunlight) and turning it into heat, and the RCE is very good at radiating heat away. Together, this ensures enough of temperature difference for the TEG to function in bright sunlight, cloudy sunlight, clear nighttime, and everything in between.

As mentioned, it’s not a lot of power (we’re talking millivolts) but the ability to passively and constantly produce across shifting environmental conditions is something new. And as a bonus, the researchers even found a novel way to create both UBSA and RCE using non-exotic materials and processes. The research paper with additional details is available here.

The ability to deliver uninterrupted power — even in tiny amounts — is a compelling goal. A few years ago we encountered a (much larger) device from a team at MIT that also aimed to turn environmental temperature fluctuations into a trickle of constant power. Their “Thermal Resonator” worked by storing heat in phase-change materials that would slowly move heat across a TEG, effectively generating continuously by stretching temperature changes out over time.

The World’s First Agricultural Right To Repair Law

April 29, 2023 by Jenny List 29 Comments

Long time readers will know that occasionally we mix up our usual subject matter with a dash of farm equipment. Usually the yellow and green variants that come from John Deere, as the agricultural manufacturer has become the poster child for all that is wrong in the fight for the right to repair. An old Deere is worth more than a nearly new one in many places, because for several years now their models have had all their parts locked down by DRM technologies such that only their own fitters can replace them. Now after a long legal fight involving many parties, the repair and parts company iFixit sound justifiably pleased as they announce the world’s first agricultural right to repair law being passed in the US state of Colorado. (Nitter)

This may sound like a small victory, and it will no doubt be followed by further rearguard actions from the industry as similar laws are tabled in other states. But in fact as we read it, with this law in place the game is de facto up for the tractor makers. Once they are required to release any access codes for the Coloradans those same codes will by extension be available to any other farmers, and though we’re guessing they won’t do this, they would be best advised to give up on the whole DRM idea and concentrate instead on making better tractors to fix their by-now-damaged brands.

It’s exciting news for everybody as it proves that right-to-repair legislation is possible, however since this applies only to agricultural machinery the battle is by no means over. Only when all machines and devices have the same protection can we truly be said to have achieved the right to repair.

We’ve reported on this story for a long time, here’s a previous piece of legislation tried in another state.