Big Chemistry: Liquefied Natural Gas

December 21, 2022 by Dan Maloney 44 Comments

The topic of energy has been top-of-mind for us since the first of our ancestors came down out of the trees looking for something to eat that wouldn’t eat them. But in a world where the neverending struggle for energy has been abstracted away to the flick of a finger on a light switch or thermostat, thanks to geopolitical forces many of us are now facing the wrath of winter with a completely different outlook on what it takes to stay warm.

The problem isn’t necessarily that we don’t have enough energy, it’s more that what we have is neither evenly distributed nor easily obtained. Moving energy from where it’s produced to where it’s needed is rarely a simple matter, and often poses significant and interesting engineering challenges. This is especially true for sources of energy that don’t pack a lot of punch into a small space, like natural gas. Getting it across a continent is challenging enough; getting it across an ocean is another thing altogether, and that’s where liquefied natural gas, or LNG, comes into the picture.

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A Single-Watt Hydroponic Lighting System

October 31, 2022 by Bryan Cockfield 24 Comments

Hydroponic systems are an increasingly popular way to grow plants indoors using a minimum of resources. Even some commercial farming operations are coming online using hydroponic growing techniques, as these methods consume much less water, land area, and other resources than traditional agricultural methods. The downside is that the required lighting systems often take an incredible amount of energy. That’s why [ColdDayApril] set up a challenge to grow a plant hydroponically using no more than a single watt.

The system is set up to grow a single pepper plant in what is known as a deep-water culture, where the plant is suspended in a nutrient solution which has everything it needs to grow. The lightning system is based around the Samsung LM301B which comes close to the physical limits for converting electricity into white light and can manage around 220 lumens. A special power supply is needed for these low-power diodes, and the light is efficiently directed towards the plant using a purpose-built reflective housing. By placing this assembly very close to the plant and adjusting it as it grows, [ColdDayApril] was able to take the pepper plant from seed to flowering in 92 days.

It’s worth noting that the rest of the system uses a little bit of energy too. A two watt fan helps circulate some air in the hydroponic enclosure, and deep-water systems usually require an air pump to oxygenate the water which uses another two watts. This is still an impressive accomplishment as most hobbyist builds use lighting systems rated in the hundreds of watts and use orders of magnitude more energy. But, if you’re willing to add some fish into the system you can mitigate some of the energy requirements needed for managing the water system even further.

Comparing Solar Energy Harvesters

October 27, 2022 by Bryan Cockfield 11 Comments

There doesn’t have to be much more to setting up a simple solar panel installation than connecting the panel to a battery. Of course we would at least recommend the use of a battery management system or charge controller to avoid damaging the battery, although in a pinch it’s not always strictly necessary. But these simple systems leave a lot on the table, and most people with any sizable amount of solar panels tend to use a maximum power point tracking (MPPT) system to increase the yield of the panels. For a really tiny installation like [Salvatore] has, you’ll want to take a look at a similar system known as a solar energy harvester.

[Salvatore] is planning to use an energy harvester at his small weather station, which is currently powered by an LDO regulator and a small solar cell. While this is fairly energy efficient, the energy harvesters that he is testing with this build will go far beyond what an LDO is capable of. The circuit actually has two energy harvesters built onto it which allows him to test the capabilities of both before he makes a decision for his weather station. Every amount of energy is critical when using the cell he has on hand, which easily fits in the palm of one’s hand.

The testing of this module isn’t complete yet, but he does have two working prototypes to test in future videos to see which one truly performs the best. For a project of this size, this is a great way to get around the problem of supplying a small amount of power to something remote. For a larger solar panel installation, you’ll definitely want to build an MPPT system though.

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Gym Equipment Converted To Generator

June 29, 2022 by Bryan Cockfield 41 Comments

Energy cannot be created or destroyed, but the most likely eventual conclusion of changing it from one form or another will be relatively useless heat. For those that workout with certain gym equipment, the change from chemical energy to heat is direct and completely wasted for anything other than keeping in shape. [Oliver] wanted to add a step in the middle to recover some of this energy, though, and built some gym equipment with a built-in generator.

Right now he has started with the obvious exercise bike stand, which lends itself to being converted to a generator quite easily. It already had a fairly rudimentary motor-like apparatus in it in order to provide mechanical resistance, so at first glance it seems like simply adding some wires in the right spots would net some energy output. This didn’t turn out to be quite so easy, but after a couple of attempts [Oliver] was able to get a trickle of energy out to charge a phone, and with some more in-depth tinkering on the motor he finally was able to get a more usable amount of energy to even charge a laptop.

He estimates around 30 watts of power can be produced with this setup, which is not bad for a motor that was never designed for anything other than mechanical resistance. We look forward to seeing some other equipment converted to produce energy too, like a rowing machine or treadmill. Or, maybe take a different route and tie the exercise equipment into the Internet connection instead.

Geothermal System Is A Real Gold Mine

May 25, 2022 by Al Williams 57 Comments

What do you get when Pacific Northwest National Laboratories takes over what was once the largest and deepest gold mine in North America? The answer might be enough energy to power 10,000,000 homes. The enhanced geothermal systems project includes the lab and several partners from academia and industry and aims to test sending fluids down boreholes so the Earth can heat them up. Hot fluids, of course, can easily create electricity.

At 4,100 feet underground, the old mine is not very convenient to get to. However, modern technology means that the equipment is largely automated so workers can carry out experiments from home using a computer or even a phone. The system itself is 7 feet long by 7 feet wide and 30 feet long. It was assembled above ground, tested, and then split into 4×4 sections for transportation deep below the surface.

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2022 Hackaday Prize: Get Your Planet-Friendly Power On!

April 27, 2022 by Elliot Williams 5 Comments

Time flies! This weekend marks the end of the first stage of the 2022 Hackaday Prize, and your chance to enter your alternative-energy projects. There are ten $500 prizes up for grabs, and there’s still time to whip up a project page over on Hackaday.io to showcase it.

In this round, we’re looking for projects that harvest their own energy — solar, wind, heat, vibration, you name it — or projects that make it easier to collect, store, or use renewable energy. Whether this is microwatts or megawatts, the scale of the project is up to you! As long as it’s using or making it easier to use clean energy, we want to see it.

So far, we’ve seen some great projects, ranging from a optimizes the tilt angle of a home solar installation to a demonstration of using a new type of lithium-ion capacitor to add solar power to smaller projects. We really love [MartMet]’s simple Bluetooth thermometer hack, which adds a supercapacitor and solar cell to an outdoor thermometer, and then uses hacked firmware to log the charge status over a year of use! We’re suckers for good data.

The sun is not the only game in town, though. There are a surprising number of projects based on human energy production in emergency situations, from cranking to shaking. Thermionic converters were new to us, but we love explorations of fringe tech. Other traditional favorites like wind and water may make more sense for larger applications. And don’t forget how you’re going to store all this juice you’ve collected.

[Nick Poole]’s thermionic converter array

[Anuradha Gunawardhana]’s 18650 Pack

In short, we’ve got a bunch of great entries, but we’re still missing yours! There’s no minute like the last minute: if you’ve done some work in clean or renewable energy, set yourself up a Hackaday.io project page now. You’ll help make all our projects cleaner, and stand a good chance of taking home some real money to boot!

Once we’ve handled power, the next round is “Reuse, Recycle, Revamp” where any tech that uses recycled parts or facilitates reuse, repair, or recycling is fair game!

High Temp Heat Engine Achieves 40% Efficiency

April 23, 2022 by Al Williams 17 Comments

People generate lots of waste heat. It makes sense that there is a desire to convert that heat into usable energy. The problem is one of efficiency. Researchers from MIT and the National Renewable Energy Lab have announced a new heat converter that they claim has 40% efficiency. Of course, there’s a catch. The temperature range for the devices starts at 1,900 °C .

The thermophotovoltaic cells are tandem devices with two cells mated on one substrate. Each cell is multiple layers of very thin and somewhat exotic materials. So this probably isn’t something you will cobble up in your basement anytime soon unless you’re already manufacturing ICs down there. It appears that the secret is in the multiple layers including a reflective one that sends any missed photons back through the stack.

The paper is pretty dense, but there’s a Sunday-supplement summary over on the MIT site. Using heat storage leads to the ability to make heat batteries, more or less, and harness what would otherwise be waste energy.

We’ve noticed a lot of interest in drawing power from hot pipes lately. All of them techniques we’ve seen rely on some kind of exotic materials.