Energy Efficient Fridge Hack

August 27, 2009 by James Munns 39 Comments

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We’ve already covered a pipe bomb mini-fridge this week, but inventor [Tom Chalko] provides us with today’s fridge hack. He noticed that chest-style (laying down, see above) freezers were more energy efficient when compared to normal stand up refrigerators at the same size, despite the colder temperatures involved. This is largely due to the fact that these chest-style freezers keep cold air in like water in a bowl, even if the lid is open. He has written a very thorough report on his findings (pdf), as well as a detailed walk through of the manageable task of converting a chest-style freezer into a chest-style fridge. In the end, his fridge only used 103 Wh of electricity on the first day to reach and maintain between 4° and 7° C (39° to 45° F), and he noted that 30% of that was just getting it up to temperature. After that, the fridge only turned on for roughly 90 seconds an hour, making it a very quiet fridge as well.

Single Can Mini Fridge

August 25, 2009 by Jakob Griffith 16 Comments

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What looks like a potential WMD, requires a huge power supply, and has several fans and wires dangling off the sides? Why a mini fridge of course! Your cubical buddy at work may have a Perfect Coffee Mug, or a USB powered fridge but it wont be as large of a caliber as [CaptPikel’s]. Little information about it is out thus far, but an Instructable is promised. We do however know that it uses 3 peltier coolers (assumed to be 60watt each) and can cool down to 46F while being underpowered! If only it held just a few more cans.

Brew Fridge Thermostat

March 22, 2009 by Eliot 32 Comments

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Reader [Will R] sent in a thermostat mod for his brew fridge. His friends had found a perfectly fine bar refrigerator and wanted to repurpose it for brewing beer. A previous batch of microbrew had been mangled by the Australian heat so they wanted something that could maintain the perfect temperature. The fridge’s built-in thermostat wouldn’t rise above 5 degrees so they had to build their own. [Will] used a 10K NTC thermistor to measure the temperature. It’s connected to an ATtiny25 microcontroller that does the comparison and determines whether to turn on the compressor. He referenced SparkFun’s relay tutorial for the switching side. Although he didn’t etch a board for this project, the design file is included along with all the code on the project site.

Robotic Beer Launching Fridge

February 26, 2007 by Eliot 13 Comments

This robotic beer launching fridge is one of those ultimate projects that you are guaranteed to see posted all over the internet today. Robots, beer, the possibility of maiming innocent bystanders… what’s not to love? I’d be lying if I said my mechanical engineering friends and I weren’t contemplating this at many points during college. Kudos to John W. Cornwell of Duke for actually pulling it off. The mini-fridge has three servos: one to elevate beer from the 10 can magazine, one to rotate the turntable, and one for cocking. Spring power is used to catapult the beer across the room. The brains of the system is an ATMega8535 and 3 intelligent H-bridges. It’s controlled by an adapted key-less entry system. It looks like they’ve wisely placed it pointing away from the tv, but I don’t know if referring to your apartment as the “man-pit” is nearly as smart. Check out some of John’s other projects: the Mentos booby-trap and the touch activated paintball gun.

[via Dirk]