Widespread use of refrigerators is a hallmark of modern society, allowing people to store food and enjoy ice and cold beverages. However, a typical refrigerator uses gasses that are not always good for the environment. Now the Berkeley National Lab says they can change that using ioncaloric cooling, a new technique that uses salt as a refrigerant.
The new technique involves using ions to drive a solid-to-liquid phase change which is endothermic. Unlike some similar proposals, the resulting liquid material would be easy to pump through a heat exchanger. In simple terms, it is the same process as salting a road to change the melting point of ice. In this case, an iodine-sodium salt and an organic solvent combine. Passing current through the material moves ions which changes the material’s melting point. When it melts, it absorbs heat. When it resolidifies, it releases heat.
Continue reading “Salty Refrigeration Is Friendly To The Environment” →
Every week, the Hackaday tip line is bombarded with offers from manufacturers who want to send us their latest and greatest device to review. The vast majority of these are ignored, simply because they don’t make sense for the sort of content we run here. For example, there’s a company out there that seems Hell-bent on sending us a folding electronic guitar for some reason.
At first, that’s what happened when CoolingStyle recently reached out to us about their Cooler Max. The email claimed it was the “World’s First AC Cooler System For Gaming Desktop”, which featured a “powerful compressor which can bring great cooling performance”, and was capable of automatically bringing your computer’s temperature down to as low as 10℃ (50°F). The single promotional shot in the email showed a rather chunky box hooked up to a gaming rig with a pair of flexible hoses, but no technical information was provided. We passed the email around the (virtual) water cooler a bit, and the consensus was that the fancy box probably contained little more than a pair of Peltier cooling modules and some RGB LEDs.
The story very nearly ended there, but there was something about the email that I couldn’t shake. If it was just using Peltier modules, then why was the box so large? What about that “powerful compressor” they mentioned? Could they be playing some cute word games, and were actually talking about a centrifugal fan? Maybe…
It bothered me enough that after a few days I got back to CoolingStyle and said we’d accept a unit to look at. I figured no matter what ended up being inside the box, it would make for an interesting story. Plus it would give me an excuse to put together another entry for my Teardowns column, a once regular feature which sadly has been neglected since I took on the title of Managing Editor.
There was only one problem…I’m no PC gamer. Once in a while I’ll boot up Kerbal Space Program, but even then, my rockets are getting rendered on integrated video. I don’t even know anyone with a gaming computer powerful enough to bolt an air conditioner to the side of the thing. But I’ve got plenty of experience pulling weird stuff apart to figure out how it works, so let’s start with that.
Continue reading “Teardown: Cooler Max Liquid Cooling System” →
One of the big stories last week was the announcement of results from clinical trials that suggest a new COVID-19 vaccine developed through the joint effort of the American and German companies Pfizer and BioNTech is strongly effective in providing immunity from the virus. In the midst of what is for many countries the second spike of the global pandemic this news has been received with elation as well as becoming the subject of much political manoeuvring.
While we currently have two vaccine candidates with very positive testing results, one of the most interesting things for us is the need to keep doses of the Pfizer/BioNTech vaccine extremely cold until they are administered. Let’s dig into details of the refrigeration problem at hand.
Continue reading “The Special Fridges Behind The COVID-19 Vaccine, Why It’s Surprisingly Difficult To Be That Cool” →
When you’re a kid, one of the surest signs of summer is hearing the happy sound of the ice cream truck crawling through the neighborhood. You don’t worry about how that magical truck is keeping the ice cream cold, only that it rolls down your street, and that the stars align and your parents give you money for a giant ice cream-cookie sandwich with the edge rolled in tiny chocolate chips.
In the early days of mobile refrigeration, ice cream trucks and other food delivery vehicles relied first on ice, and then dry ice to keep perishables cold. Someone eventually invented an electric cooling system, but those had to be recharged periodically at power stations. There was also a short-lived mechanical system, but it was highly susceptible to road vibrations.
Until Frederick McKinley Jones came along, mobile refrigeration was fledgling, and sources of perishable food were extremely localized and limited. In the early 1940s, Frederick patented the first practical automated refrigeration system for trucks, and it revolutionized the shipping and storage of food and medicine.
Continue reading “Fresh Food Year Round? You Can Thank Frederick McKinley Jones” →
Many people with Multiple Sclerosis have sensitivity to heat. When the core body temperature of an MS sufferer rises, symptoms get worse, leading to fatigue, weakness, pain, and numbness. For his entry to the Hackaday Prize, [extremerockets] is finding a solution. He’s developing a wearable, personal cooling device that keeps the wearer at a comfortable temperature.
The device is based on a wearable shirt outfitted with small tubes filled with a cooling gel. This setup is extremely similar to the inner garments worn by astronauts on spacewalks, and is the smallest and most efficient way to keep a person’s core body temperature down.
Unlike a lot of projects dealing with heating and cooling, [extremerockets] isn’t working with Peltiers or thermoelectric modules; they’re terribly inefficient and not the right engineering choice for something that’s going to be battery-powered. Instead, [extremerockets] is building a miniature refrigeration unit, complete with a real refrigeration cycle. There are compressors, valves, and heat exchanges in this build, demonstrating that [extremerockets] has at least some idea what he’s doing. It’s a great project, and one we can’t wait to see a working prototype of.
[Ed] from Ed’s Systems, aka [Aussie50] took some time to demo his high pressure Frankenstein air compressor he stitched together from two refrigeration compressors. The two Danfoss SC15 compressors can produce upwards of 400psi and can run all day at the 300 psi range without overheating. The dual units may get up to pressure quickly considering the small accumulator “tank”, but high CFM isn’t the goal with this build. [Ed] uses the system to massacre some LCD panels with lead, ball bearings, and other high speed projectiles shot from a modified sandblasting gun. Just a bit of air at 400 psi is all you need for this terminator toy.
Don’t think the destruction is wasteful either; [Ed] strives to repair, rebuild, reuse, repurpose and a few other R’s before carefully separating and sorting all the bits for recycling. This modification included lots of salvaged hardware from older teardowns such as high pressure hoses, connectors, accumulator and pressure cutoff switches.
At first it seems strange to see something engineered for R22 refrigerant working so well compressing air. Morphing refrigeration systems into air compressor service is something [Ed] has been doing for a long time. In older videos, “fail and succeed”, [Ed] shows the ins and outs of building silent air compressors using higher capacity storage tanks. Being no stranger to all variations of domestic and commercial refrigeration systems, [Ed] keeps home built air compressors running safe and problem free for years.
Don’t think this is the only afterlife for old refrigeration compressors, we’ve seen them suck too. You’ll get a few more tidbits, and can watch [Ed’s] video overview of his home built compressor after the break.
Continue reading “High Pressure Air Compressor Using A Pair Of Refrigeration Compressors” →