Another treat to come home to.

Clever devices, in my control panel days for high humidity climates all we could do was fit a heater to drive out humidity, not the best solution when the ambient temperature is over 30 degrees

Phil Collins

That's what I expected. I think it only increased by about 2C over th e duration of the video, but I was was watching the temp as well as the more obvious humidity change and noticed it change. :)

The module does generate a small amount of heat, but no more than a typical indicator once it's initially dried itself out.

Big Clive

Ok, I just missed it then. I watched it via Patreon, then didn't see a link to the site in the comments here. I did a search for Rohsal, as you'd spelled it in one of the comments, Google asked if I meant Rosahl instead. :) Those things aren't exactly cheap, but I can see uses for them. I used to work for a company that sold Ethernet Switching Boxes and Side of the House Residential Boxes. We were always having problems with humidity and heat, these might have helped with the humidity. I did note that during your test, the humidity went down, but the temp went up slightly. Do you know if that was because the bench light was just heating the box, or does the module generate heat as a side product?

That's the correct site. I did put a link in the video description on YouTube.

Big Clive

You were going to provide a link to their website, but I don't see one. You might have spelled the name wrong also, I did find this site during a search and the modules look like what you were testing. <a href="https://www.micro-dehumidifier.com/products/price-list-rosahl-dehumidifiers/" rel="nofollow noopener" target="_blank">https://www.micro-dehumidifier.com/products/price-list-rosahl-dehumidifiers/</a>

consider recording to mono or mixing to mono when you finalize the video? listening to this video was headache inducing.

kn0tsin

We still have a chunky VCR from the early 1980s with lots of buttons and dials and a wired remote. I'm sure if its belts are replaced that it would still operate. The reason we kept it so long is that it could play worn out tapes that the modern VCRs struggled to play, such as workout VHS tapes that my parents played daily. I don't recall it having a dew lamp. I think the issue with fridges/freezers would be dealing with the heat separation between the inside and outside of the dehumidifier module. For example, even if the module works at -18C, the problem would be frost building up on the outside of the module.

Seán Byrne

This would have been great in the old days for VHS tape players. It was a drag waiting for the dew lamp to go out so the player would run. Anyone else here old enough to remember VHS? These would be good for frost-free refrigerators if they could handle the volume of water vapor. hmmmm

Nani Isobel

You could always flip it around and fill the cabinet with hydrogen. That's when the real fun begins.

I really like the way it works like a peltier, but for transferring humidity instead of heat. Going by the specifications, it looks like energy efficiency could be an issue scaling it up. Assuming the MDL-7 consumes 4W to remove its rated 16g/day capacity, over 24 hours, that would be 96Wh for 16g. This works out at roughly 167ml per kWh. For comparison, my refrigerant based dehumidifier collects about 1.2 litres for each kWh energy usage, operating around 22C 55%. This rate drops the cooler the room gets and similarly at lower humidity levels, but so far never seen it collect less than around 600ml per kWh even during chilly winter days. If they can scale it up and achieve energy efficiency even of let's say 500ml per kWh like what desiccant dehumidifiers typically achieve, it certainly would make a great home dehumidifier without the fan noise or compressor hum on refrigerant units.

Seán Byrne

Never knew these existed until now! I wonder what (other) cool applications they can be used in? THANKS CLIVE YOU ROCK MAN

Michael Thompson

I read in the info from both sites that it splits the hydrogen and oxygen passes them through the membrane then recombines them. They also say that you can reverse the 3V and it will work in reverse, but will greatly reduce the lifetime of the unit, they say if you want to keep the humidity to a certain level use two of them facing opposite directions.

Cleveland Prescott

Rohsal do have water weight ratings on their datasheets based on fairly high humidity.

Big Clive

🤔Hmm.. Would it be possible to set up an experiment to measure how much water this panel would be able to extract under the worst/best possible conditions over a 24h, 48h, 1week period and the power consumption. Also. I wonder what the expected lifetime of this thing is. And also if the working lifetime is different in high humidity vs. medium vs. low humidity.

Bo Holbo Rasmussen

Thank you for showing us these, really cool tech, these would be so useful!

Kevin Bornewasser

No. It doesn't seem to go down below about 30%. (I need to do a longer test.)

Big Clive

One of these would be useful for my car, it's one that is known for leaks and the body control computer has just succumbed to moisture. One of these on the plastic case of the BCU or a larger one on the bulkhead of the car would be a nice easy way to get rid of some of that moisture.

Matt Tester

Cigar Humidor ? with 2 one to dehumidify one to re- humidify. Currently use propylene glycol

Ian James

i wonder if they would be good for my rifle safe

Steven Cox

Filling an electrical cabinet with oxygen sounds like it might have its own risks.

My fathers little a**h**e dog could be interesting on the inside...

Scott Miller

I had that thought but at 3v with such a low current it is not likely to be producing any great volume, I'm thinking that the process might rely on the chemical bond re-forming on the outside for this to work properly. Fascinating item.

The Tinkering Shed

Could you collect the gas off the discharge side and see if is hydrogen rich? Might be a good source of hydrogen

Did it get down to 0?

this looks like it would be good for 3D printer protection .. and keeping your filaments dry

God 420

For the love of god don’t send anything living to Big Clive, HE WILL TAKE IT APART!! :)

Lostngone

Creating an oxygen-rich environment in a sealed case with electronics seems like a bad idea...

George Dorn

That’s incredible! How long until we see these in headlights to stop them steaming up? It would be interesting to see if you can run it from 2x AA batteries and how low they’d last.

evilution

Hm. I think I will have to order some of those. We have a lot of outdoor cctv, alarmsystems etc at work that would definitely benefit from a dehumidifier. Especially since it runs on that low power.