Just when you thought ice cube-creation technology had peaked, a team of engineering students from San Jose State University has come up an ice maker that has zero carbon footprint. It’s more than an eco-party trick — consider it an electricity-free alternative to refrigeration and air conditioning, which is critical if you happen to be somewhere off of the electrical grid, like in the developing world or in a disaster zone.
It works like this: the solar icemaker uses a refrigerant liquid that evaporates when exposed to the sun. The vapor travels through pipes that come into contact an absorbent material, which cools when the sun goes down. Once the slow-cooling absorbent hits 104°F, the refrigerant turns back into a liquid and its temperature drops like a rock to below freezing because of pressure differences. Put some water next to the evaporator’s exterior and, presto, ice.
A typical icemaker uses electricity to run a compressor to do this work, but the solar icemaker just uses solar energy, with no moving parts. And the systems are sealed, so barring a leak, they'll never need replenishing. The icemaker makes about 14 pounds of ice per day — more than enough for the margaritas at your end-of-summer barbecue. The students' prototype isn't available yet, but maybe next summer….
editor@dvice.com
By MacBeth at 5:44 PM ON 08/27/08
Wasn't Harrison Ford in a movie about that called Mosquito Coast?
By savychris at 5:30 PM ON 08/28/08
What is the coolant being used?!?
Sounds like it could be useful for other projects as well.
Thanks!
Chris
By jrhee at 5:32 PM ON 08/28/08
That movie was the inspiration for our project! In the movie, Harrison Ford uses fire (instead of the sun) for the heat source. -Prof. J. Rhee, SJSU
By Chris@wellplanet.org at 9:40 PM ON 08/28/08
just wanted to let you know that i have posted this information on my site as well as a link to this information. this is great stuff.
By Pall.e at 11:08 AM ON 08/29/08
I once read about a project to use freezers to desalinate water. I wonder if this would useful in places like Sahara Africa to purify salt-water. I know it has it's downsides, but just a thought.
By cawwot at 2:31 PM ON 08/29/08
Very nice work, I look forward to hearing more about this in the future.
By baltee at 3:31 PM ON 08/29/08
The technology for doing this has been around for years, along with the instructions for diy'ng it. Great to see it being brought out again it the light, so to speak... :) Hopefully they're using a coolant other than the typical ammonia.
Cheers
By LUMINOUS at 4:46 PM ON 08/29/08
This is just another re-invention of the wheel. Companies such as Energy Concepts of Annapolis, MD, had their solar ice makers under endurance test for years at Sandia National Labs. I took some pictures of it at the lab in 2006. The machine was made in 1994.
By tallpaul420 at 4:15 PM ON 08/30/08
This is a nice start but I have been pushing this technology to deaf ears. The DOE knew of this technology a decade ago but they didn't like it. Now there is a US grant for this technology but most of the money went to solar thermal panels. Our company is relocating to the EU for production. Too bad USA, you're going to lag the pack again...
By Peltier at 12:06 AM ON 09/01/08
Too bad its to big (and prolly heavy too) for my car's roof. I'll stick to a Peltier fridge with PV panels or via an inverter for now.
By Moose at 10:24 PM ON 09/01/08
Agreed, they aren't the first. CSIRO in Australia developed a solar freezer back in the 1980's (IIRC). I believe that it didn't work like conventional fridges / freezers either.
By backwash at 11:20 AM ON 09/02/08
There was a professor from MIT that was doing this using zeolite mineral as the absorbent and water as the refrigerant. Try Google zeolite refrigerator.
By ivywarlord at 2:01 PM ON 09/15/08
This device rocks. Great work you guys!
By kevin at 1:25 AM ON 10/02/08
Wow. I was working out some figures on a cycle that was exactly like this, but it used propane for the heat source instead of a solar reflector. Finally something where solar polar makes a bit of sense. Nice work!
By Paul Noyelles at 7:26 AM ON 10/13/08
The S.T.E.V.E.N. Foundation did this 12 years ago (I have a PDF copy of it) and it had me searching the internet for more info on this concept. I saw the need for a small unit to make ice to keep medical supplies cool at remote loactions when I was a UN Peacekeeper in East Timor. My hope is for a corporate sponsor to help produce these so 3rd world countries can have them where no electricity is available for such things as keeping medicine cold and safe. Good luck with continued development.
By Hope at 9:21 PM ON 10/21/08
Come on guys, where are the specs...or are you just going to be another bunch of lame bread heads...spread your knowledge before you die
By Popa at 12:39 AM ON 10/22/08
The PDF mentioned above is located at http://www.solarhaven.org/AmmoniaAbsorptionIcemaker.pdf This is a 1996 document that shows pictures and basic but not detailed plans.
By jeanlan02 at 12:04 PM ON 10/24/08
In 1979, in Ouagadougou, I dreamed to build up solar refrigerators for my projects. Unfortunately, lacking information and technology I had to put that idea on the ice until now. As a former UNDP s/m , I am very excited seing that what I needed 30 years ago is now available. Thanks to Paul and to Popa for the information regarding the "PDF Doc". I will have a look at the website suggested by Popa for the plans. I am collecting simple technologies (appropriate technologies, as they are called) to apply in my sustainable development projects, as I am still working in the UN programmes occasionally.