Hacked Heating Instruments for the DIY Biology Lab

[Justin] from The Thought Emporium takes on a common molecular biology problem with these homebrew heating instruments for the DIY biology lab.

The action at the molecular biology bench boils down to a few simple tasks: suck stuff, spit stuff, cool stuff, and heat stuff. Pipettes take care of the sucking and spitting, while ice buckets and refrigerators do the cooling. The heating, however, can be problematic; vessels of various sizes need to be accommodated at different, carefully controlled temperatures. It’s not uncommon to see dozens of different incubators, heat blocks, heat plates, and even walk-in environmental chambers in the …read more

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Lily Power Pods Make the Seebeck Effect Look Good

The Seebeck effect (part of the broader thermoelectric effect) is how a difference in temperature can be directly converted into a voltage, and it is the operating principle behind things like thermocouples and Peltier junctions. Harnessing this effect in an effort to wrangle a useful electrical current out of the environment has led to some interesting ideas, like the Lily Power Pods by [Josh Starnes].

What’s interesting about this particular design is that the artistic angle crosses over with functionality. Electrically speaking, the pods have one side of the thermoelectric generator heated by the sun while the other is cooled …read more

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Big Power, Little Power, Tiny Power, Zap!

Our Hackaday Prize Challenges are evaluated by a panel of judges who examine every entry to see how they fare against judging criteria. With prize money at stake, it makes sense we want to make sure it is done right. But we also have our Hackaday Prize achievements, with less at stake leading to a more free-wheeling way to recognize projects that catch our eye. Most of the achievements center around fun topics that aren’t related to any particular challenge, but it’s a little different for the Infinite Improbability achievement. This achievement was unlocked by any project that impressed with …read more

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A Flashlight Powered by Your Hot Little Hands

We are smack-dab in the middle of our Energy Harvesting Challenge, and [wasimashu] might have this one in the palm of his hand. Imagine a compact flashlight that doesn’t need batteries or bulbs. You’d buy a 10-pack and stash them everywhere, right? If there’s nothing that will leak or break or expire in your lifetime, why not have a bunch of them around?

Infinity uses nothing but body heat to power a single white LED. It only needs a five-degree temperature difference between the air and your hand to work, so it should be good in pretty much any environment. …read more

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Thermoelectric Fan Harvests Wood Stove Heat Junkyard Style

Anyone who heats with a wood stove knows that the experience is completely different from typical central heating. It’s not for everyone, though, and it’s certainly not without its trade-offs. One of the chief complaints is getting heat away from the stove and into other areas of the house, and many owners turn on an electric fan to circulate the heated air.

That’s hardly in the green nature of wood heating, though, and fans can be noisy. So something like this heat-powered stove-top fan can come in handy. Such fans, which use Peltier devices to power a small electric motor, …read more

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Thermoelectric Generator Shines Where the Sun Doesn’t

For off-grid renewable electricity, solar seems to make sense. Just throw some PV panels on the roof and you’re all set to stick it to the man, right? But the dirty little secret of the king of clean energy is that very few places on the planet get the sort of sunshine needed to make residential PV panels worth their installation cost in the short term, and the long-term value proposition isn’t very good either.

The drearier places on the planet might benefit from this high-power thermoelectric generator (TEG) developed and tested by [TegwynTwmffat] for use on a wood burning  …read more

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Thermoelectric Paint Opens Prospect Of Easier Energy Harvesting

We will all be used to the thermoelectric effect in our electronic devices. The property of a junction of dissimilar conductors to either generate electricity from a difference in temperature (the Seebeck effect), or heating or cooling the junction (the Peltier effect). Every time we use a thermocouple or one of those mini beer fridges, we’re taking advantage of it.

Practical commercial thermoelectric arrays take the form of a grid of semiconductor junctions wired in series, with a cold side and a hot side. For a Peltier array the cold side drops in temperature and the hot side rises in …read more

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Thermoelectric Dry Ice Generator Does Not Work (Yet)

[Pabr] is trying to make dry ice the hard way by building a thermoelectric dry ice generator. The project is a well planned round trip through thermodynamics and cryogenics with a hard landing on the icy grounds of trial and error.

While dry ice can be obtained with simpler methods, for example by venting gaseous CO2 from fire extinguishers and collecting the forming CO2 flakes, [pabr’s] method is indeed attractive as a more compact solid-state solution. The setup uses a four stage Peltier element, which uses four Peltier stages to achieve a high temperature differential. With sufficient cooling on the …read more

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