Ask Hackaday: Is It Time For Waste Heat And Cold Area Heating To Shine?

April 12, 2022 by Jenny List 82 Comments

It’s difficult to escape the topic of energy supply at the moment, with the geopolitical situation surrounding the invasion of Ukraine leaving the natural gas supply to an entire continent in jeopardy. Fortunately we’re watching the green shoots of an early spring here in the Northern hemisphere so the worst of the winter weather is behind us, but industrial customers can take no such solace from the season and will have to weather whatever price hikes are to come. Every alternative idea for energy supply is on the table, and with the parallel imperative of decarbonising the economy this goes beyond the short term into a future without so much need to rely on gas.

The Future is Cloudy

A district heating plant in Vienna, Austria. Joadl, CC BY-SA 3.0 AT

A collaboration between a Finnish district heating network and Microsoft caught our eye because the location of a new data centre for the tech giant was chosen specifically to supply waste heat to the network, rather than releasing it to the environment. It’s not uncommon at all for European cities to use district heating networks but they are normally supplied by waste incinerators, boilers, or combined heat and power stations. The use of data centre waste heat is a novelty, as is in particular the siting of the data centre being dictated by the network.
Continue reading “Ask Hackaday: Is It Time For Waste Heat And Cold Area Heating To Shine?” →

Just What On Earth Is A Therm?

April 7, 2022 by Jenny List 86 Comments

With the news here in Europe full of the effect of the war in Ukraine on gas supplies and consequently, prices, there it was on the radio news: a unit of measurement so uniquely British that nobody uses it in the real world and nobody even has a clue what it really means. We’re speaking of the Therm, one of those words from our grandparents’ era of coal gas powered Belling cookers and Geyser water heaters hanging over the bath, which has somehow hung on in the popular imagination as a mysterious unit of domestic gas referred to only in the mass market news media. What on earth is a therm, and why are we still hearing it on the news in the UK?

You can’t Buy A Therm

Asking the internet what a therm is reveals the answer, it’s 100,000 BTU. What’s a BTU? A British Thermal Unit, another anachronistic measurement five decades after the UK went metric, it’s the amount of energy required to raise a pound of water by a degree Fahrenheit. Which in turn is about 1,054 joules, in today’s measurements. So a therm is thus a unit of energy, can we take a look at our gas meters and see how many of them we’ve used this winter? Not so fast, because gas isn’t sold by the therm. Older gas meters had cubic feet on them, and we’re guessing that now they’re calibrated in cubic meters. We can’t even buy a therm of gas, so why on earth are the British media still using it? Continue reading “Just What On Earth Is A Therm?” →

Bike On Over To The Campground

March 20, 2022 by Bryan Cockfield 9 Comments

Like many of us, [Paul] enjoys occasionally hitching up his tow-behind camper and heading out to the wilderness to get away from it all at his favorite campsite. Unlike the vast majority of those who share his passion for the outdoors, though, [Paul] is hitching his camper up to a bicycle. Both the camper and the bike are custom built from the ground up, and this video shows us a little more details on [Paul]’s preferred mode of transportation.

While he is known for building custom vehicles of one sort or another, this latest one is a more traditional bicycle frame that he has modified only slightly to fit a recumbent-style seat and a small gas-powered motor. Even though the motor is decades old, it started right up and gives the power needed to pull the custom camper. [Paul] builds one-person campers like this out of corrugated plastic for durability and light weight, and this one is specifically designed for his size and sleeping style. It includes everything needed for a night under the stars, too, including a stove, storage compartments, and a few windows.

With the bike and camper combined weighing in at just over 200 pounds, the motor can be used as a pedal-assist device thanks to the clever engineering behind a front-wheel-drive pedal system on this bike. With all of that custom fabrication, [Paul] is free to head out to the wilderness without all the encumbrances (and high price) of traditional motor vehicle-based camping. For those curious about some of [Paul]’s other vehicle creations, take a look at this tiny speedboat for one.

Continue reading “Bike On Over To The Campground” →

Portable Pizza Oven Has Temperature Level Over 900

January 24, 2022 by Bryan Cockfield 36 Comments

While it’s possible to make pizza from scratch at home right down to the dough itself, it’ll be a struggle to replicate the taste and exquisite mouthfeel without a pizza oven. Pizzas cook best at temperatures well over the 260°C/500°F limit on most household ovens while pizza ovens can typically get much hotter than that. Most of us won’t have the resources to put a commercial grade wood-fired brick oven in our homes, but the next best thing is this portable pizza oven from [Andrew W].

The build starts with some sheet metal to form the outer and inner covers for the oven. [Andrew] has found with some testing that a curved shape seems to produce the best results, so the sheet metal goes through rollers to get its shape before being welded together. With the oven’s rough shape completed, he fabricates two different burners. One sits at the back of the oven with its own diffuser to keep the oven as hot as possible and the other sits underneath a cordierite stone to heat from the bottom. Both are fed gas from custom copper plumbing and when it fires up it reaches temperatures hot enough that it can cook a pizza in just a few minutes. With some foldable legs the oven also ends up being fairly portable, and its small size means that it can heat up faster than a conventional oven too.

This is [Andrew]’s third prototype oven, and it seems like he has the recipe perfected. In fact, we featured one of his previous versions almost two years ago and are excited to see the progress he’s made in this build. The only downside to having something like this would be the potential health implications of always being able to make delicious pizzas, but that is a risk we’d be willing to take.

Continue reading “Portable Pizza Oven Has Temperature Level Over 900” →

Carbon Sequestration As A Service Doesn’t Quite Add Up

October 15, 2021 by Lewin Day 128 Comments

Burning fossil fuels releases carbon dioxide into the atmosphere. While most attempts to reduce greenhouse-gas emissions focus on reducing the amount of CO₂ output, there are other alternatives. Carbon capture and sequestration has been an active area of research for quite some time. Being able to take carbon dioxide straight out of the air and store it in a stable manner would allow us to reduce levels in the atmosphere and could make a big difference when it comes to climate change.

A recent project by a company called Climeworks is claiming to be doing just that, and are running it as a subscription service. The company has just opened up its latest plant in Iceland, and hopes to literally suck greenhouses gases out of the air. Today, we’ll examine whether or not this technology is a viable tool in the fight against climate change.

Continue reading “Carbon Sequestration As A Service Doesn’t Quite Add Up” →

Building A Stump Grinder From The Ground Up

July 27, 2021 by Bryan Cockfield 7 Comments

Felling a tree properly is a skill that takes some practice to master, especially without causing any injuries or property damage. Getting the tree cut down though is sometimes only half of the battle, as the stump and roots need to be addressed as well. Unless you have a few years to wait for them to naturally decompose you might want to employ a stump grinder, and unless you want to spend a chunk of money on a stump grinding service or buy your own, you might want to do what [Workshop from Scratch] did and build your own.

This stump grinder isn’t anything to scoff at, either, and might even fool some into thinking it’s a consumer grade tool from a big box store. Far from it though, as almost everything down to the frame is custom machined specifically for this build. The only thing that isn’t built from scratch, including the cutting wheel, is the beefy 15 horsepower motor. Once it gets going it is able to carve stumps down to the ground in no time thanks especially to some gear reductions in the drive line from the motor to the cutting head.

Before anyone mentions safety, it looks like [Workshop from Scratch] has made some upgrades since his last project which was a gas-powered metal cutting chainsaw. Since then it looks like he has upgraded the sheet metal to something a little thicker, even though a stump grinder has arguably lower risk due to the slower speed of the cutting wheel and also to the fact that the cutting medium is wood and not metal. There are also brakes and an emergency shutoff switch. It sure seems like a fine addition to his collection of completely custom tools.

Continue reading “Building A Stump Grinder From The Ground Up” →

Joker Monitor Keeps An Eye On Hazardous Gas Levels

July 23, 2021 by Lewin Day 12 Comments

The Joker is a popular character in the Batman franchise, and at times uses poisonous gases as part of his criminal repertoire. That inspired this fun project by [kutluhan_aktar], which aims to monitor the level of harmful gases in the air.

The project doesn’t use just one gas sensor, but several! It packs the MQ-2, MQ-3, MQ-4, MQ-6, and MQ-9. This gives it sensitivity to a huge variety of combustible gases, as well as detecting carbon monoxide. The sensors are read by an Arduino Nano, which displays results on an RGB LED as well as an attached IPS screen.

Readings from each sensor can be selected by using an infrared remote. In order to best work as a safety device, however, it could be more useful to have the Arduino automatically cycle through each sensor, checking them periodically and raising an alarm in the event of a high reading.

The whole project is built on a custom PCB which is artfully constructed with an image of the Joker himself. It helps to make the project a bit more of a display piece, and speaks to the aesthetic skills of its creator.

It’s a fun build, and one that could be mighty capable with a few software tweaks. With that said, if you’re working in a space with real hazards from combustible gases, it may be worth investing in some properly rated safety equipment rather than relying on an Arduino project.

Incidentally, if you’d like to improve the results from using such gas sensors, we’ve looked at that in the past. Video after the break.

Continue reading “Joker Monitor Keeps An Eye On Hazardous Gas Levels” →