Senoko natural gas and oil-fired power station, Singapore in 2007. (Credit: Terence Ong)

Singapore’s 4300 Km Undersea Transmission Line With Australia Clears Regulatory Hurdle

October 23, 2024 by Maya Posch 22 Comments

The proposed AAPowerLink transmission line between Darwin (Australia) and Singapore. (Credit: Sun Cable)

Recently Singapore’s Energy Market Authority (EMA) granted Sun Cable conditional approval for its transmission line with Australia. Singapore has been faced for years now with the dilemma that its population’s energy needs keep increasing year-over-year, while it has very little space to build out its energy-producing infrastructure, least of all renewables with their massive footprints. This has left Singapore virtually completely dependent on natural gas-burning thermal plants. Continue reading “Singapore’s 4300 Km Undersea Transmission Line With Australia Clears Regulatory Hurdle” →

For Desalination, Follow The Sun

October 22, 2024 by Al Williams 24 Comments

It’s easy to use electricity — solar-generated or otherwise — to desalinate water. However, traditional systems require a steady source of power. Since solar panels don’t always produce electricity, these methods require some way to store or acquire power when the solar cells are in the dark or shaded. But MIT engineers have a fresh idea for solar-powered desalination plants: modify the workload to account for the amount of solar energy available.

This isn’t just a theory. They’ve tested community-sized prototypes in New Mexico for six months. The systems are made especially for desalinating brackish groundwater, which is accessible to more people than seawater. The goal is to bring potable water to areas where water supplies are challenging without requiring external power or batteries.

The process used is known as “flexible batch electrodialysis” and differs from the more common reverse osmosis method. Reverse osmosis, however, requires a steady power source as it uses pressure to pump water through a membrane. Electrodialysis is amenable to power fluctuations, and a model-based controller determines the optimal settings for the amount of energy available.

There are other ways to use the sun to remove salt from water. MIT has dabbled in that process, too, at a variety of different scales.

Pac-Man Ghost Helps With Air Quality Sensing

October 21, 2024 by Bryan Cockfield 13 Comments

In the past, building construction methods generally didn’t worry much about air quality. There were enough gaps around windows, doors, siding, and flooring that a house could naturally “breathe” and do a decent enough job of making sure the occupants didn’t suffocate. Modern buildings, on the other hand, are extremely concerned with efficiency and go to great lengths to ensure that no air leaks in or out. This can be a problem for occupants though and generally requires some sort of mechanical ventilation, but to be on the safe side and keep an eye on it a CO2 sensor like this unique Pac-Man-inspired monitor can be helpful.

Although there are some ways to approximate indoor air quality with inexpensive sensors, [Tobias] decided on a dedicated CO2 sensor for accuracy and effectiveness, despite its relatively large cost of around $30. An ESP32 handles the data from the sensor and then outputs the results to an array of LEDs hidden inside a ghost modeled after the ones from the classic arcade game Pac-Man. There are 17 WS2812B LEDs in total installed on a custom PCB, with everything held together in the custom 3D printed ghost-shaped case. The LEDs change from green to red as the air quality gets worse, although a few preserve the ghost’s white eyes even as the colors change.

For anyone looking to recreate this project and keep an eye on their own air quality, [Tobias] has made everything from the code, the PCB, and the 3D printer files open source, and has used accessible hardware in the build as well. Although the CO2 sensors can indeed be pricey, there are a few less expensive ways of keeping an eye on indoor air quality. Some of these methods attempt to approximate CO2 levels indirectly, but current consensus is that there’s no real substitute for taking this measurement directly if that’s the metric targeted for your own air quality.

COBB Tuning Hit With $2.9 Million Fine Over Emissions Defeat Devices

September 20, 2024 by Maya Posch 110 Comments

Recently, the EPA and COBB Tuning have settled after the latter was sued for providing emissions control defeating equipment. As per the EPA’s settlement details document, COBB Tuning have since 2015 provided customers with the means to disable certain emission controls in cars, in addition to selling aftermarket exhaust pipes with insufficient catalytic systems. As part of the settlement, COBB Tuning will have to destroy any remaining device, delete any such features from its custom tuning software and otherwise take measures to fully comply with the Clean Air Act, in addition to paying a $2,914,000 civil fine.

The tuning of cars has come a long way from the 1960s when tweaking the carburetor air-fuel ratios was the way to get more power. These days cars not only have multiple layers of computers and sensor systems that constantly monitor and tweak the car’s systems, they also have a myriad of emission controls, ranging from permissible air-fuel ratios to catalytic converters. It’s little surprise that these systems can significantly impact the raw performance one might extract from a car’s engine, but if the exhaust of nitrogen-oxides and other pollutants is to be kept within legal limits, simply deleting these limits is not a permissible option.

COBB Tuning proclaimed that they weren’t aware of these issues, and that they never marketed these features as ’emission controls defeating’. They were however aware of issues regarding their products, which is why they announced ‘Project Green Speed’ in 2022, which supposedly would have brought COBB into compliance. Now it would seem that the EPA did find fault despite this, and COBB was forced to making adjustments.

Although perhaps not as egregious as modifying diesel trucks to ‘roll coal’, federal law has made it abundantly clear that if you really want to have fun tweaking and tuning your car without pesky environmental laws getting in the way, you could consider switching to electric drivetrains, even if they’re mind-numbingly easy to make performant compared to internal combustion engines.

Mothbox Watches Bugs, So You — Or Your Grad Students — Don’t Have To

September 19, 2024 by Dan Maloney 8 Comments

To the extent that one has strong feelings about insects, they tend toward the extremes of a spectrum that runs from a complete fascination with their diversity and the specializations they’ve evolved to exploit unique and ultra-narrow ecological niches, and “Eww, ick! Kill it!” It’s pretty clear that [Dr. Andy Quitmeyer] and his team tend toward the former, and while they love their bugs, spending all night watching them is a tough enough gig that they came up with Mothbox, the automated insect monitor.

Insect censuses are valuable tools for assessing the state of an ecosystem, especially insects’ vast numbers, short lifespan, and proximity to the base of the food chain. Mothbox is designed to be deployed in insect-rich environments and automatically recognize and tally the moths it sees. It uses an Arducam and Raspberry Pi for image capture, plus an array of UV and visible LEDs, all in a weatherproof enclosure. The moths are attracted to the light and fly between the camera and a plain white background, where an image is captured. YOLO v8 locates all the moths in the image, crops them out, and sends them to BioCLIP, a vision model for organismal biology that appears similar to something we’ve seen before. The model automatically sorts the moths by taxonomic features and keeps a running tally of which species it sees.

Mothbox is open source and the site has a ton of build information if you’re keen to start bug hunting, plus plenty of pictures of actual deployments, which should serve as nightmare fuel to the insectophobes out there.

Trees Turned Into Wind Turbines, Non-Destructively

September 18, 2024 by Bryan Cockfield 57 Comments

Trees and forests are an incredibly important natural resource — not only for lumber and agricultural products, but also because they maintain a huge amount of biodiversity, stabilize their local environments, and help combat climate change as a way to sequester atmospheric carbon. But the one thing they don’t do is make electricity. At least, not directly. [Concept Crafted Creations] is working on solving this issue by essentially turning an unmodified tree into a kind of wind turbine.

The idea works by first attaching a linear generator to the trunk of a tree. This generator has a hand-wound set of coils on the outside, with permanent magnets on a shaft that can travel up and down inside the set of coils. The motion to power the generator comes from a set of ropes connected high up in the tree’s branches. When the wind moves the branches, the ropes transfer the energy to a 3D printed rotational mechanism attached to a gearbox, which then pumps the generator up and down. The more ropes, branches, and generators attached to a tree the more electricity can be produced.

Admittedly, this project is still a proof-of-concept, although the currently deployed prototype seems promising. [Concept Crafted Creations] hopes to work with others building similar devices to improve on the idea and build more refined prototypes in the future. It’s also not the only way of building a wind energy generator outside of the traditional bladed design, either. It’s possible to build a wind-powered generator with no moving parts that uses vibrations instead of rotational motion as well.

Continue reading “Trees Turned Into Wind Turbines, Non-Destructively” →

Mowing The Lawn With Lasers, For Science

September 3, 2024 by Maya Posch 34 Comments

Cutting grass with lasers works great in a test setup. (Credit: Allen Pan, YouTube)

Wouldn’t it be cool if you could cut the grass with lasers? Everyone knows that lasers are basically magic, and if you strap a diode laser or two to a lawn mower, it should slice through those pesky blades of grass with zero effort. Cue [Allen Pan]’s video on doing exactly this, demonstrating in the process that we do in fact live in a physics-based universe, and lasers are not magical light sabers that will just slice and dice without effort.

The first attempt to attach two diode lasers in a spinning configuration like the cutting blades on a traditional lawn mower led to the obvious focusing issues (fixed by removing the focusing lenses) and short contact time. Effectively, while these diode lasers can cut blades of grass, you need to give them some time to do the work. Naturally, this meant adding more lasers in a stationary grid, like creating a Resident Evil-style cutting grid, only for grass instead of intruders.

Does this work? Sort of. Especially thick grass has a lot of moisture in it, which the lasers have to boil off before they can do the cutting. As [Allen] and co-conspirator found out, this also risks igniting a lawn fire in especially thick grass. The best attempt to cut the lawn with lasers appears to have been made two years ago by [rctestflight], who used a stationary, 40 watt diode laser sweeping across an area. When placed on a (slowly) moving platform this could cut the lawn in a matter of days, whereas low-tech rapidly spinning blades would need at least a couple of minutes.

Obviously the answer is to toss out those weak diode lasers and get started with kW-level chemical lasers. We’re definitely looking forward to seeing those attempts, and the safety methods required to not turn it into a laser safety PSA.

Continue reading “Mowing The Lawn With Lasers, For Science” →