I agree with Robotguy; There's a need for refrigerated storage of medical items and for air-conditioning of medical facilities in certain circumstances, if not for personal comfort, as well as for food storage and preservation.

Somewhere I have a document on creating a solar-powered batch freezer, which uses ammonia as a refrigerant in a solar collector, then after sufficient energy is collected, the pressurized ammonia is dumped via an expansion orifice inside an insulated box, creating a batch of ice by expansion of the ammonia. This is just like a regular air-conditioner, except running in intermittent cycles instead of continuously.
The ice is then moved to an icebox to refrigerate vaccines or seeds or whatever.
This system requires attention daily to operate, but could be a valuable system for remote areas, and once installed doesn't have many moving parts or upkeep.
I'll see if I can dig up the document when I get home.

I've thought that a sufficiently sized system could produce ice for a superinsulated ice-house, with a daily batch of ice being made and dumped down a chute (for example) into the ice-house to keep foods in cold storage.
Other refrigerants could be used, such as propane.
There are lots of options.

For food preservation, instead of refrigeration, I'd like to see small-scale electron-beam food irradiators become available. As opposed to gamma-ray irradiators, which use radioactive materials to bombard foods with sterilizing gamma rays, electron-beam systems use a high-energy beam of electrons (similar to what's inside a CRT tv or monitor) to sterilize food and medical materials with much safer electron radiation. There's also X-ray irradiation, which has greater penetration.

A system the size of a home oven could protect food for an entire village, when combined with airtight containers like glass jars with sealing lids. Such a system could make meats and dairy products almost shelf-stable for consumers who don't have access to electrically operated (and polluting with CFCs) normal refrigerators.
I'd heard about electron beam sterilizers coming onto the market, but I think they were talking about large-scale systems for food processing facilities. Has anyone heard of smaller-scale "appliance" irradiators? If not, maybe we could design such a beast.
Blah blah safety blah blah. Yeah, yeah, I hear you already.... "radiation" can be dangerous. So is standing in the sun. Done right it would be a great boon to mankind. Let's do it right.

the link brings up an empty page.

As a northerner, I have difficulty agreeing with the assertion above this reply. This is partially because of an understanding of passive cooling techniques used for thousands of years, but more because I have difficulty accepting the basic premise.

If am omission is glaring, then its non-existence, once established, should be apparent to everyone, from Africa to the Arctic. In a modern and wealthy society we can afford to demand comfort. However, millions of people die daily and have little interest in anything they cannot eat.

It is my opinion that as this community develops there will be information outside the core GVCS that deals with air conditioning and refrigeration, but I do not believe this information belongs on the core list. One of the essentials for being on the list is: "Essential contribution to an infrastructure for living and working." Granted, comfort is important, but both air conditioning and refrigeration are, in my opinion, non-essential modern conveniences. Moreover, it is important to consider the energy demands of such devices. Are they consistent with our ideals?

While I do slightly question the presence of a Bakery Oven and Dairy Milker, I am familiar with both milking and baking and know the amazing impact these devices have upon time and production volume.

I think it is important to maintain a clear vision of our mission.

@Daniel - Thank you for your input, I will have to make a point to be more careful with my usage of English; though, unless my math is wrong, 730,000,000 does not exceed the current world population.

According to Wikipedia, the number of starvation related deaths is difficult to come by, but malnutrition affects a mere 14% of the world.

Also, thank you for clarifying the point I was attempting to make. While I feel they should not be part of the core system, developing information on them is not bad.

I think I may not have clearly expressed that my response was not calculated to say that the modern methods of food storage and living space climate control that has become normative in modern America is not important. Rather, I was arguing that a complex, active model of each is not important enough to make the core list.

I do think that the Bakery Oven would be useful for more than just wheat bread.

To a person with a high fever caused by Malaria or Dengue, air conditioning is beautiful. In the most poverty-stricken areas of the world, if they have an electricity supply then it is because they have a medical clinic (and nothing like what we would call a medical clinic in the developed world) with a refrigerator for preserving medicines.

Producing your own food supply is wonderful but food needs to be preserved - in many cases refrigerated or frozen. If you really want to create a global village construction set, something to help people lift themselves out of grinding poverty and bring them into modern civilization, then we have to look at these things that are simply taken for granted in the West.

How about incorporating a modular reversible heat pump in the GVCS? It could be used to heat and cool houses and greenhouses, to refrigerate food and medicine, for geothermal energy and many other applications. SHPEGS have pretty much designed an open-source one already - see http://www.shpegs.org/ammonia.html

in my opinion the personal fabrication machines, Liberator, lifetrac+attachments should take priority over all other machines in GVCS. Some of the machines could probably even be omitted.

@eBell, I will chime in with agreement too. I think it is easy to get caught up with the "we could do anything" idea and forget that we are trying to build a foundation for a new way of doing things-- not trying to make a space colony.

>> To design and build a extra-low energy consumption refrigeration is one of the top projects in my "to do list".
You may be interested in this - http://openfarmtech.org/wiki/Refrigeration#Converting_a_freezer_to_a_high-efficiency_fridge

It's a very simple conversion that turns a chest freezer (about $200) into a fridge that uses only 150 Watt-hours a day, compared to 1000 Watt-hours a day for a normal fridge. You need to buy a thermostat to do the conversion, which is $150 at most.

Also, put the fridge in the coldest possible place, so it'll use less energy. Maybe bury it.

I will definitively try to hack a freezer termostat someday, but I need first to find a realy cheap chest freezer to experiment with. A new chest freezer here starts at about US$ 400,00.

But, In fact, I'm following another track. I'm experimenting with and trying to improve the Zeer pot:

http://en.wikipedia.org/wiki/Pot-in-pot_refrigerator

http://www.practicalaction.org/food-production/zeerpots


I get a 10 degree(celsius) drop in temperature with the original design. I'm trying to figure out how to combine the evaporative cooling with forced convection, geothermal cooling and better insulation to get a bigger drop.

Check out "indirect" or multi-stage evaporative cooling: http://jbarrownews.blogspot.com/2007/09/introduction-to-indirect-evaporative.html. You are limited to the wet bulb temperature, though. So you can cool a cabinet that a refrigerator sits in, but will likely need a supplementary cooler for some foods to not spoil.