A green job of the future - hand cleaning solar panels. U.S. Department of Agriculture, CC BY-SA 4.0, via Wikimedia Commons

Claim: Solar Powered Refrigerators would Solve African Food Waste

Essay by Eric Worrall

If only people like International Environment and Resource Policy Post Doc Abay Yimere talked to the engineering department before discussing technology solutions.

Installing solar-powered refrigerators in developing countries is an effective way to reduce hunger and slow climate change

Published: January 20, 2023 12.36am AEDT

Abay Yimere
Postdoctoral Scholar in International Environment and Resource Policy, Tufts University

Food loss and waste are major problems around the world. When food is tossed aside or allowed to spoil, it makes economies less productive and leaves people hungry. 

It also harms Earth’s climate by generating methane, a potent greenhouse gas. Food loss and waste accounts for 4% of global greenhouse gas emissions. If food waste were a country, it would be the third-largest emitter in the world, ahead of India and behind only China and the U.S.

..

Expanding food cold chains to the world’s least-developed countries can have enormous impacts. But it also raises concerns if it’s not done in a way that avoids contributing to climate change.

Existing refrigeration systems release hydrochlorofluorocarbons, or HCFCs, and hydrofluorocarbons, or HFCs, which are extremely potent greenhouse gases. Producing electricity with fossil fuels to power these systems also worsens climate change. For these reasons, exporting traditional cold chains to developing countries is not environmentally and socially sustainable. 

Instead, developing countries need cold chains that run on renewable energy and use alternative refrigerants with lower climate impacts. As a scholar focusing on sustainable development, green growth and climate change, I believe that expanding cold chains in the developing world – particularly sub-Saharan Africa – will not only benefit the environment but also provide important social benefits, such as empowering women.

Read more: https://theconversation.com/installing-solar-powered-refrigerators-in-developing-countries-is-an-effective-way-to-reduce-hunger-and-slow-climate-change-195143

A friend uses solar power to run his fridge – 10KW of solar panels + a battery backup, to run two household fridge freezers and a freezer. Total cost about $10,000 USD of solar panels and battery – for one family of four. Even so, he has to switch over to grid power a few times per year, when a prolonged period of cloudy weather prevents his battery charging.

The cost of the battery alone is a showstopper. Without the battery, my friend’s solar fridges would be close to useless. With the battery, they only let him down sometimes. But how many poor Africans can afford a $10,000 family fridge? Or even a $3000 family fridge?

There is a better solution – an absorption refrigerator.

Absorbtion refrigerators are simple, cheap, 1920s technology, which can be driven by any source of heat – including, but not limited to solar energy. They used to be very common – my grandpa had a kerosene powered cooler chest size portable absorption fridge he kept into the back of his pickup truck, for camping trips.

The following video from 1939 explains how an absorption fridge works.

Absorption fridges don’t need electricity, and have no moving parts, though they can use electricity to supply the heat they need to operate. A fire, normally propane or kerosene, drives a cyclic series of chemical reactions which keeps the interior of the fridge cold.

Such fridges could easily be adapted to use a wood fuelled fire box, they only need a source of heat – it doesn’t matter how the heat is produced. They don’t use CFCs, the cooling cycle uses ammonia, water and hydrogen – so they could be recharged with minimal effort in the field using cheap chemicals.

Such fridges could be assembled by a competent welder from a blueprint. Africa has plenty of skilled machine welders and metal workers, nothing gets thrown away in Africa until it is truly beyond repair. Like I said, there are no moving parts, there are no expensive, difficult to obtain components – just an arrangement of gas tight pipes and radiators.

All skilled African tradesmen would need is the knowhow to assemble the fridge, out of parts they likely already have in their worksheds.

By all means run the absorption fridge on solar power, when sunlight is available – a cheap solar concentrator would be enough, they wouldn’t need expensive solar panels. A molten salt heat reservoir, like the salt in an off peak electric powered wall heater, could possibly be used to keep the refrigerator running at night, or the owner could light up the firebox, and power the fridge from coal or wood after the sun goes down.

Of course, some of the absorption fridges might be adapted by the owners to work on fossil fuel, even if they didn’t start out that way – so maybe that rules them out as a perfect “climate solution”, even if they would be an incredibly cheap and accessible solution to Africa’s cold food storage problem.

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mkelly
January 22, 2023 6:15 am

Most pop up campers have one of these installed. Mine as is typical used the propane. All I needed to do was light it.

Scissor
Reply to  mkelly
January 22, 2023 6:42 am

Interesting technology. It would seem to be a somewhat complex combination of chemical vs physical phase transformations.

Chemically is it driven by acid/base reactions between water and ammonia with heat needed to drive phase flow and decomposition of reaction products?

Hydrogen must be needed to maintain the right physical properties of the mixture to allow fluid circulation.

I wonder whether Peltier coolers could compete on efficiency.

Last edited 16 days ago by Scissor
davidmhoffer
Reply to  Scissor
January 22, 2023 9:38 am

I did a deep dive on Peltier coolers 20 years go, they weren’t even close on the efficiency front. I dought they have changed much, else we would see consumer fridges and freezers switching over to them.

Gregg Eshelman
Reply to  davidmhoffer
January 22, 2023 9:18 pm

Peltier coolers are most efficient when run at about 50% voltage. So instead of using one full tilt at 12 volts, use two of the same module in series so they’re both running at 6 volts. The heat pump effect will be spread out more to make better use of the heat sinks.

With a switch setup to change them to parallel connection a dual Peltier cooler could get even colder, at the cost of higher power use.

I have seen mini fridges in some hotels that use a Peltier. I assume they’ve come down in price to less than the conventional compressor style, and they can have the same interior capacity in a smaller overall size because half to 2/3 of the bottom isn’t taken up by the compressor.

But that may change due to the new 12V DC micro compressors that have been introduced recently, thanks to a US military contract that got canceled.

There are several portable fridge/freezers available using those micro compressors. It will only take a change in packaging to configure them as upright mini fridges. Some of the coolers are made to be used with the lid up or standing on end, but of course they look like a cooler standing on end.

What would really be great is a compact engine exhaust heat to electricity converter. That could eliminate the alternator in a vehicle and generating the electricity from the exhaust heat would put zero load on the engine.

MarkW
Reply to  Gregg Eshelman
January 23, 2023 9:51 pm

I suspect the quietness of the Peltier might be the deciding feature for hotel fridges.

Hasbeen
Reply to  Scissor
January 22, 2023 4:24 pm

I had one of these on my yacht when I was cruising & working in the Pacific Islands. Only small, 1.5 cubic ft, it used very little fuel to run it. One 20Lb gas bottle of propane would run it, & a little 2 burner stove for just over 2 months.

This was very handy, as with a spare gas bottle I could go 4 months between having to visit somewhere civilised enough to refill the bottles.

Tom Johnson
Reply to  Hasbeen
January 22, 2023 6:36 pm

I’ve always considered propane on a boat to be an absolute no-no. It’s heavier than air, so any leak sinks into the bilge, forming an explosive mixture that stays in place until ignited. I also recall that ammonia in refrigerators for home use was discontinued for safety issues.

Hasbeen
Reply to  Tom Johnson
January 22, 2023 8:50 pm

Tom I lived on that yacht for 15 years, sailed 53,000 miles, & for half of that time had a petrol engine. All No Nos of course, but I’m still here to tell that these things work very well, if used by intelligent, careful, practical people, & the equipment was installed properly in the first place.

Gregg Eshelman
Reply to  Tom Johnson
January 22, 2023 9:21 pm

Install a bilge blower to keep air circulating. Boats with inboard engines usually have a blower to ventilate the engine compartment before starting, to remove the possibility of igniting gasoline or other fumes.

Curious George
Reply to  mkelly
January 22, 2023 10:52 am

“fossil fuels to power these systems also worsen climate change”
As always, you can be either practical or progressive.

Peter C.
Reply to  mkelly
January 22, 2023 6:32 pm

Pretty much a standard offering in any Canadian RV, issues I have with them is it requires the RV to be on a fairly level ground because of the way the burner works. Also you can’t use 12 volts for the heater as power requirements are too high.Oh, terribly expensive to replace as they are not repairable.Most people replace with 12v compressor fridges when the propane one dies.

Gregg Eshelman
Reply to  Peter C.
January 22, 2023 9:22 pm

Three way (gas, 12VDC, 110VAC) absorption fridges for RVs have existed for decades, and able to work at significant inclines.

Peter C.
Reply to  Gregg Eshelman
January 23, 2023 1:30 pm

Last one I had in my c class RV , the manual specified no more than 3 degrees fore and aft and 6 degrees maximum side to side. Your mileage may vary but mine would stop working beyond these limits.My 2014 camper fridge manual does not quote specific limits,just says fairly level, whatever that means.

MarkW
Reply to  Peter C.
January 23, 2023 9:53 pm

My grand dad’s camper had a gas fridge, I can remember him breaking out the blocks and level every time we parked.

bj
January 22, 2023 6:15 am

Should Climate Change not be called Climate Control as they want to control the climate?

MarkH
Reply to  bj
January 22, 2023 1:07 pm

They don’t even really want to control the climate. They want to control the people. The climate (or anything else, like COVID) is just a handy excuse.

David Dibbell
January 22, 2023 6:26 am

“Existing refrigeration systems release hydrochlorofluorocarbons, or HCFCs, and hydrofluorocarbons, or HFCs, which are extremely potent greenhouse gases.”

No, refrigeration equipment does NOT “release” the refrigerant. It may escape unintentionally by leakage, but that is all. There are strict measures against intentional release. And what warming has ever been isolated for reliable attribution to these “extremely potent greenhouse gases?” None of it!

As Eric says, “If only people like International Environment and Resource Policy Post Doc Abay Yimere talked to the engineering department before discussing technology solutions.” Good point. But I’m not hopeful for this to start happening.

Last edited 16 days ago by David Dibbell
Scissor
Reply to  David Dibbell
January 22, 2023 7:11 am

Researchers are bestowed favor by grant reviewers if they use words like “potent greenhouse gases.”

You’re right about release and recovery of HCFCs. As I understand a popular narrative among researchers and regulators in this area, HCF23 is formed as a byproduct of some HCF manufacturing in Asia and is just released into the air, which is a cause of concern.

Mason
Reply to  David Dibbell
January 22, 2023 7:24 am

Regarding the statement – he was referring to the cold chain. Unfortunately, he is way off base. Nearly all of the cold chain is using ammonia as the refrigerant. And to scissor, HFC23 is a byproduct HCFC22 manufacture. The days of this being released to the atmosphere are long gone. The early global warming credits were mostly for capturing 23. I attended a Carbon forum in Beijing a decade ago and the bankers and lawyers were talking about building more 22 plants to get the credits for capturing 23. 23 is the primary refrigerant for ultra low refrigeration. Gore’s Chicago Climate Exchange primarily made their millions on 23 capture.

Gregg Eshelman
Reply to  Mason
January 22, 2023 9:24 pm

Yup, some companies got busted for making the gasses just to destroy them and get paid for it.

Editor
Reply to  David Dibbell
January 22, 2023 8:03 am

There are international agreements in place to reduce the use of the most harmful refrigerants. Many household refrigerators are now using simple propane/butane.

Last edited 16 days ago by Kip Hansen
MarkW
Reply to  Kip Hansen
January 23, 2023 9:55 pm

Except the claim that they were harmful had as much science behind it as the global warming nonsense.

Archibald Tuttle
Reply to  David Dibbell
January 22, 2023 8:37 am

I agree that refrigerant is generally not released from self contained refrigeration units and the obligatory hand wringing of the confirmation bias addled researcher is wasted words (albeit, the EPA estimates refrigerant life for heat pumps (split systems that are field connected technology) at only 7 years and, if one worries about this kind of thing, the EPA mandated refrigerant to protect the ozone layer: R410A, does have a very high global warming potential (GWP) and extreme operating pressures compared to other refrigerants that have half the GWP and very little chemical interaction potential with ozone but were banned nonetheless, e.g. R22. Of course competing objective made R410A obsolete from EPAs perspective when it was introduced at their behest! Yet we have built an EPA directed subsidized infrastructure of R410A systems that will be with us for years to come, thanks EPA).

To be fair, I hardly think we could expect third world efforts to place a high degree of focus on refrigerant recovery but this ignores that the refrigerant circuit on such self contained appliances is virtually never serviced anymore. The most significant potential for refrigerant release is physical defrosting (or course most westerners will ask, what is defrosting, so see defrosting note below). The big service headaches are digital controls; they should stick to very simply repeatable control strategies for any refrigerators headed into the bush. But even if I accepted the premise that one should worry about this stuff, this guy does not appear to have grasped that the industry is well ahead of his concerns with over a 3rd of 1000 million refrigerators delivered annually using flammable refrigerants iwth low operating pressures and virtually 0 GWP. The key headwinds are concern about flammability which at first sounds almost insurmountable but given the small charges and extemely minimal risk of discharge this is not a significant issue for the future electric fleet of home refrigerators and you quite likely have one in your own kitchen already without knowing it.

For desseminating refrigeration to the non-grided developing world, ammonia cycle certainly has more potential than solar powered electric although @Eric Worrells recitation of the costs and complications of his friends solar effort imports a first world standard to the conception. As we all know from losing power, well insulated refrigeration doesn’t necessarily need signifcant backup to weather a power outage of less than a day. You just don’t open the fridge or freezer and it is effectively energy storage on its own. @Eric Worrell is not wrong that, ironically, heat could be stored in mass to operate ammonia cycle that used solar concentration during the day. Of course it is also possible to store cold.

But this might be over thinking entry level tech nology. In the west we wouldn’t contemplate harnessing the circadian rhythms of our deglutition and dietetic choice to the vagaries of whether the sun was shining; but if you have no refrigeration, refrigeration that you have to operate carefully where you might occasionally be forced to resort to use or lose it or traditional preservation methods in long solar droughts might still be preferable to none. And the idea of solar refrigeration and minimal storage might dovetail with the notion of individual or microgrids supplying other benefits of electricity to rural 3rd world settings.

Another issue for both ammonia and solar powered conceptions is the western convenience of automated defrosting is pretty much off the table and present western electric refrigerator designs wouldn’t be directly applicable–again favoring off the shelf ammonia cycle. Defrost is currently managed in typical home refrigerators by ditching the original designs that dispersed the evaporator around the cooling cabinet and instead circulating cold through the refrigerator box with a fan and defrosting those coils with resistance electric heat. This pushes the limits of solar adaptability as it creates instant high resistance loads for periods of 15 to 20 minutes. There is no source for defrosting in current designs without electricity, so there are no self-defrosting ammonia cycle refrigerators. (It is remotely conceivable a 4-way valve running the refrigeration cycle backwards could be designed–which is how they defrost the outdoor unit of heat pumps in the winter and why I have to explain to folks why they get cold air out of their heat pump occasionally during heating season). That said, there are efforts to make “cycle defrost” easier to the point of mirroring self defrost: https://www.warehouseappliance.com/blog/ez-defrost-system-for-gas-refrigerators/ that again could be suitable either for ammonia cycle or electric refrigeration designed for operation on the most efficient solar proviso.

But I confirm the bottom line of @Eric Worrall’s post, the researcher, Abay Yimire deosn’t appear to have seriously dealt with these technologies in the field; and while he has ideas that in theory could work, they aren’t tested for cost benefit against ammonia cycle. The aversion to fossil fuel creates a barrier to the benefits he correctly predicts could inure to 3rd world households and especially women in those settings. While he see’s himself as attempting to effect this liberation, limiting himself to solar as the sole source is the kind of presupposition that will in fact slow the very process he hopes to catalyze. And yet it will be people like him from whom the international do-gooders take their lead as to what to preach at, and supply to, the third world.

rhs
January 22, 2023 6:27 am

Once propane and natural gas are banned in the name saving the planet what fuel source will be available?
https://wattsupwiththat.com/2023/01/21/open-thread-47/#comment-3669638
/sarcasm

Steve Case
Reply to  rhs
January 22, 2023 6:42 am

Why the sarcasm tag? Banning natural gas and petroleum derived products such as propane is exactly what the climate crusaders intend to do. Read what they say. You should believe them. A century ago there was a very well known German politician who wrote a book outlining his plan and it wasn’t taken seriously. It should been.

Steve Case
January 22, 2023 6:34 am

Mobile homes aka RVs have propane commonly known as gas refrigerators.

That aside, some of the assertions above:

     It also harms Earth’s climate by generating methane, a potent greenhouse gas.
     Food loss and waste accounts for 4% of global greenhouse gas emissions.
     If food waste were a country, it would be the third-largest emitter in the world,
     ahead of India and behind only China and the U.S.

The continued claims based on the the Global Warming Potential numbers that can be found in the IPCC reports is mathematic slight of hand that produces meaningless large numbers. You are never told (business as usual) how methane and HCFCs will actually increase global temperatures. Less than 0.05°C i.e., essentially zero.

Jeff Alberts
Reply to  Steve Case
January 22, 2023 9:17 am

Isn’t the methane produced by rotting food part of the cycle? IOW, no new methane/carbon is added.

DMacKenzie
January 22, 2023 6:41 am

The Crosley icy-ball was low tech and sorta worked for those off grid….
https://crosleyautoclub.com/IcyBall/crosley_icyball.html

Mike McMillan
Reply to  DMacKenzie
January 22, 2023 7:32 am

Crosley was into everything. When I was a kid, we had a Crosley tv set, and the Kramers down the street had two Crosley sedans rotting away in the back yard. Our fridge was genuine Frigidaire though. Gotta admire folks who come up with off-the-wall solutions and make them work.

Mike McMillan
Reply to  Mike McMillan
January 22, 2023 1:55 pm

The tv chassis had an RCA type socket on the back that was labelled for a color converter.

Joao Martins
January 22, 2023 7:00 am

Something is missing: the reference to the amount and percent of food waste in Africa.

(my very wild and unsupported by facts guess is that most food waste is wasted in the northern hemisphere, where there is plenty of food; where food is scarce, people tend to preserve it and reduce spoilage to a minimum).

That statistic would show if this is a real problem in Africa, or nothing but a fearmongering lobbying text to sell unnecessary but expensive gadgets to Africans.

Sweet Old Bob
Reply to  Joao Martins
January 22, 2023 7:14 am
Editor
Reply to  Joao Martins
January 22, 2023 8:12 am

Joao ==> Yes, I’ve worked with the poor in the Dominican Republic. They do not waste much. They do it by buying today’s food today. They store next to nothing in the home — certainly no perishables. Many home have refrigerators –to use as rodent and insect free cupboards — there is almost never a dependable supply of electricity to keep the unit cold.

Food that the poor there can’t consume and is at risk of spoiling simply gets given to a neighbor or someone even poorer than they.

Denis
January 22, 2023 7:34 am

DItto methane which Happer and Wijngaarden have shown has an undetectably small warming effect.

cilo
January 22, 2023 7:41 am

Methinks some miss the point of the blah-blah postgrad environmentalist blah-blah. What s/he/it is discussing is not technology, food security or happy Africans. What it wants, is “extending the cold chain into Africa”, as if we don’t have fridges. Bro’/ sis/ what-thingey my mate, you can buy an ice cold cola under a tree in the Kaokoveld as easily as the mud building on the outskirts of Dar-es-Salaam.
What there is a shortage of, is the prepacked, over-processed, additive-addled gunk that Nestlé and Cargill is shoving down the cancer-riddled West’s throat. For that, they need an intact cold chain. Of course they will probably still ship the near-expiry gunk, and cause as much of a disaster as upon the Amazon, but the legal proof of an intact cold chain will always win in an ‘independent’ court.
Let’s hope they don’t try follow Baal Gates’ example, and attempt to emulate the coca-cola effect

Editor
Reply to  cilo
January 22, 2023 8:19 am

cilo ==> Great rant — but in the villages and outlying areas with no dependable electrical supply, home refrigeration is very rare — one needs a dependable supply of electrical power.

Thus food is stored in what looks like a refrigerator, but that big white box is not cold.

The butcher in town as a freezer for the meat — because he has a generator to supply his own power. The people in the village pay for that generator in the prices of the meat they buy — but the meat is not spoiled…which is the whole idea.

It is almost never a lack of some technology — it is a simple lack of most everything.

That’s why we call them the profoundly poor.

The starting point is basic electrification.

DMacKenzie
Reply to  Kip Hansen
January 22, 2023 8:36 am

“The starting point is basic electrification.”
Great point, Kip. When I was a little kid, “Rural Electrification”, was under way. My father and grandfather worked for the power company for 2 weeks, paid for power poles, and we ended up with 208 volt single phase power that you could run a couple of 3/4 HP motors on, including the water well pump, washing machine, a welding machine, lots of lighting. In my old age, I now realize that the effect on our family’s standard of living and various forms of “wealth” was immense.

Last edited 16 days ago by DMacKenzie
1saveenergy
Reply to  Kip Hansen
January 22, 2023 10:29 am

“The starting point is basic electrification.”

Hang on … if we start letting the profoundly poor have basic electrification, then they will become richer (eventually caching up with us), so we wont have the rich/poor dividing line( ‘every one is equal’ is one of the tenets of communism), a lot of people wont like that.
In the capitalistic world, to be successful you have to be rich,
and to appear rich you need the profoundly poor.

cilo
Reply to  1saveenergy
January 23, 2023 12:00 am

Here’s a guy that gets it!

cilo
Reply to  Kip Hansen
January 22, 2023 11:51 pm

Yeah, I don’t mind being told I rant, used to it. Besides, it gives me opportunity to rub stuff in people’s faces.
Below find a picture of a third-world ‘butchery’. I shall forego wasting data on uploading their ‘restaurants’.
Generators, while available, are not common, and used only for high-value products, such as beer and coke and breathing apparatus down a muddy hole digging cobalt, as well as ice for those with “white boxes”. Meat is sold the day the animal dies. The hygiene would horrify any libtard into voluminous screaming fits of rage against the patriarchy. It is the customer’s job to get rid if the blowfly eggs and maggots. That is why semitic cultures in the hot desert have divine proscription against pork .
As for that ‘butcher in town’, he be far, far away from where the people eat. Mostly they serve government and corporate employees with electrified homes. No government or mining offices, no lectrix, you carry your water in a plastic bucket, and you buy your food from whomever hold some in his hand for sale. Even if you draw a salary.
Thusly ranted, I bid Kip a happy day further…
P.S. I post this not to prove the backwardness of Africa, I prefer scraping maggots to poisonous nitrite salts from America. Just because we are different does make us less. Dirt does not make you stupid the way artificial sugar does…

MEAT FOR SALE AT ROADSIDE (2).jpg
Last edited 15 days ago by cilo
Editor
January 22, 2023 8:00 am

Eric ==> Many family camps in the Northeast used kerosene and propane powered refrigerators/freezers all through the 20th century. I have owned campers and motor-homes, each of which come with a combination propane-or-electric unit.

China produces these by the millions, available for a few hundred dollars.

The problem for the profoundly poor is not the availability of refrigerators. Even very poor countries have refrigerator repair shops (on the sidewalk) that can solder broken pipes and refill refrigerant. The problem is that there is no power — no electric.

So you can give them a propane or kerosene powered refrigerator and the problem will shift to —- can’t afford the propane or propane not available this week or can’t afford the kerosene.

When we donated refrigerator/freezers to community health clinics, we always donated multi-fuel types — electric or propane usually. These automatically shift to the propane when the electric supply goes off. But this solution still requires having the money to pay for the electric and/or the propane — which must be available.

The profound problems of the poor are almost never technical — they are as simple as the fact that these people have almost nothing at all. Certainly nothing to spare.

Fran
January 22, 2023 8:54 am

Before we got a kerosene fridge, we always had last night’s leftovers for lunch. Milk was boiled and used within 24 h. But I cannot remember why my parents abandoned the fridge – probably needed wick maintenance as I seem to remember it smelled more than hurricane lanterns.

rpercifield
January 22, 2023 9:03 am

Some corrections here:

  1. Cu8rrent refrigerators in most of the world do not currently use CFCs.
  2. The US has switched to to R600a or equivalent per the Montreal Protocols.
  3. Europe has been using these types of refrigerants for years.
  4. Most international compliant refrigerators use non-CFC as well.

The “Absorption Refrigerator Systems” are common in various portable non-AC mains available applications, but are inefficient, and to not meet current IEC and DOE energy requirements. Using a solar array even with a battery storage supplement will require backup for compressor based systems, as another commenter has stated.

There are two ways to improve efficiency, insulation to the outside world, and energy transfer.

The thicker the insulating wall and higher the R value, the more efficient will be the system from a heat transfer need. almost all heat the system must move from a steady state is that which flows through the walls into the compartment.

The better the heat transfer system using forced air to remove heat from the stored products, transfer to the evaporator, and the heat from the condenser will also improve system efficiency.

The actual compressor and pumps can help as well, however there is only so much that can be done to improve this since this mechanical system is already highly optimized in the current state of the art.

Food preservation is a good place to go for many people, however, not everyone’s needs are the same. In China they have very small refrigerators since they shop almost every day. In the US large is the rule in most places, and people shop far less often. The type of food prepared and eaten will determine what effects food preservation will bring. In many places it mat be very little. People who assume what happens in their own lives as being valid in other places are narrow minded and have very little grip upon reality.

Editor
Reply to  rpercifield
January 22, 2023 10:53 am

rpercifield ==> Not sure these are as true as you think:

1) Current refrigerators in most of the world – NEW refrigerators in the Western and Modern World no longer use CFCs. That much is true. There must be millions and millions of legacy refrigerators out there. China has been accused openly of violating the CFCs mandate.

2) In China they have very small refrigerators since they shop almost every day. In general, in the third world, people shop every day because the have no or only small refrigerators. Or, can only afford a small (what we call in the US, an office mini-frig.) A full sized frig in the US the current cost averages about $1900.

No one (well, maybe Eric) has suggested replacing modern high-efficiency non-CFC frigs with “Absorption Refrigerator Systems”. That’s a silly idea and impractical.

Eric isn’t talking about efficiency — just countering the idea of the article the quotes.

Modern EU/UK/US frigs certaintly could be made more efficient — and the first place to start is get rid of the front-opening doors. Every sailor knows the refirgerator is hos biggest energy draw, and if he can, builds in a top-loading frig that doesn’t automatically dump all the precious cold air on the floor every time he opens it. And, uses 8 inches of high R-value solid-smoke foam insulation.

That said, the solution for the poor of the 3rd World is basic electrification — by any means locally possible — 24/7 a/c service — even 50 amps or less per home would serve to start.

HAS
Reply to  Kip Hansen
January 22, 2023 12:05 pm

Both our freezer, and fridge freezer uses drawers – both Japanese made though.

rpercifield
Reply to  Kip Hansen
January 22, 2023 12:22 pm

The US has been using non-CFC refrigerant for several years, and while there is a significant installed base, most communities have a recycling program available to recover the CFC contained in the sealed system. Europe and other parts of the world are even earlier.

I have both been to and designed refrigerators for the China Market, and can indeed tell that your assessment is wrong. They do not use refrigerators the same way we do in the home setting. The larger units have been available, but are seen as useful in China. This is the same for Europe and other parts of the world as well. The larger fridges are not as useful to the average person in may places, since their practices for food prep and consumption are different.

Door opening and closing is not the primary path for heat ingress for a refrigerator system. Air has very little thermal mass and even if you open the door and all the cold air spills out, as it will, that air carries very little thermal energy as to be insignificantly small to the other thermal mass to the system. The data shows that the ambient temp of the room where the fridge and R value of the walls and door are the primary function of efficiency. This is so critical that there are times that vacuum panels are placed into the walls and doors to increase the R Value.

Opening and closing of the doors do affect the frost loading on the evaporator coils since this latent moisture must be removed to reduce the air temp, and that is why in high efficiency units door opening and closing are tracked to optimize defrost cycles.

I do not know whether a significant amount of food would be saved on the African continent by use of refrigeration. My dealing with people who have lived in the more impoverished areas have told me personally other things are much more important than a fridge in the home. A fridge in the medical clinic or one in a central food distribution type of entity, yes, but not in the home quite yet. Spend the money on clean water, and low smoke cooking first in open dung or wood fires.

Jeff Alberts
Reply to  Kip Hansen
January 22, 2023 1:14 pm

What’s a frig? Fridge?

Editor
Reply to  Jeff Alberts
January 23, 2023 11:06 am

Jeff ==> “Fridge” is a short form of a commercial brand name.

MarkW
Reply to  Kip Hansen
January 23, 2023 9:59 pm

Refrigerator is a brand name?

Jeff Alberts
Reply to  Kip Hansen
January 28, 2023 7:14 am

Which one? Frigidaire? That would be “frig”, but it doesn’t work.

Jeff Alberts
January 22, 2023 9:14 am

The cost of the battery alone is a showstopper. Without the battery, my friend’s solar fridges would be close to useless. With the battery, they only let him down sometimes. But how many poor Africans can afford a $10,000 family fridge? Or even a $3000 family fridge?”

No problem. Just give 100 billion bucks to the kletpocrat who runs that country, and voila! No more hunger! Or something.

cilo
Reply to  Jeff Alberts
January 23, 2023 12:08 am

Even more important: Who can afford the security guards to look after those loverley, desire-awakening, lusciously run-awayable batteries?
Tomorrow we find out how easy it is to carry off them pretty sunboards on yer roof…
You do not solve poverty by giving people things, because the ones deserving of those gifts, are usually not the armed gangsters who need it most. Whomever you give it to, it ends up with the gangsters, at any level of society.

Erik Magnuson
January 22, 2023 9:32 am

There are a number of electric/mechanical refrigerators (a opposed to Peltier effect) that will work on a few hundred watt-hours per day, with some running off of 12 or 24VDC. Something like 100 to 150W of solar panels along with a 12V/100A-hr battery would be more than sufficient to supply the fridge in a reasonably sunny climate.

This reminds me of what cell phones have done to improve the economy of many of these areas as it promotes significantly more trade between villages.

Editor
Reply to  Erik Magnuson
January 22, 2023 10:54 am

Erik ==> Give us a link to the supplier please.

old cocky
Reply to  Kip Hansen
January 22, 2023 12:44 pm

Yes, it sounds interesting.

Erik Magnuson
Reply to  Kip Hansen
January 22, 2023 6:47 pm

Kip,

The attached link claims 9.6 A-hrs/day at 12VDC for a 1.8 cu fridge at 32C. The site also claims that a 45W module is adequate.
https://bensdiscountsupply.com/collections/solar-refrigerators/products/sundanzer-dcr50-50-litre-liter-1-8-cubic-foot-solar-dc-12v-24v-chest-refrigerator?variant=31422458790003

I thought the price was lower than what mentioned in the above link, but a reasonable sized storage battery should be able to handle several cloudy days.

Editor
Reply to  Erik Magnuson
January 23, 2023 11:12 am

Erik ==> The Sundanzer looks a lot like a top-loading sailboat refrigerator/freezer. At 1.8 cubic feet, it is very very small. But, maybe better than nothing.

At $1100 a bit pricey.

Most cruisers end up building in a custom made unit, built into the cabinetry of the galley — 8 – 10 inches of insulation, the compressor and condenser coils often in the bilges where is it is cooler. Sometimes the condenser coils are on the outside of the hull so the heat goes into the sea. My refrigeation compressor was under the sink in the head.

All boats made for long-distance cruising and live aboard on the hook

Erik Magnuson
Reply to  Kip Hansen
January 23, 2023 8:38 pm

Yeah, $1,100 is a bit much, but I have a hazy memory of seeing a considerably lower price for that unit in the past. Could be an interesting task to figure out what is the lowest overall cost by buying a cheaper unit and buying a larger solar panel and back-up battery.

A solar powered refrigerator could be the lowest overall cost for an area that’s far away from existing power lines and too low of a population to justify connecting to a grid.

I’ve seen stories of boat refrigerators using aerogels for improved insulation.

John Hultquist
January 22, 2023 9:36 am

Seems to me the proposal to use wood is misdirected. Dried manure, maybe?
Anyway, there is a cultural/capitalistic/rule-of-law aspect that needs to be addressed in the profoundly poor countries.

In the USA, early electrical power was supplied by local folks with money and/or towns with local support. Most town histories will chronicle the development. The local facilities grew and eventually became larger.
Read the history at this link for context:
City-of-Ellensburg-Light-Department-History (civicplus.com)

Rural homes were not electrified until much later.
President Roosevelt created the REA on May 11, 1935 with Executive Order No. 7037, under powers granted by the Emergency Relief Appropriation Act of 1935 [1]. The goal of the REA was to bring electricity to America’s rural areas. While cities had enjoyed electric power for many years, in 1935 “fewer than 11 of every 100 U.S. farms were receiving central station electric service.” The main problem was that the power companies were unwilling and/or unable to string wires over long distances, across farmland and back country, at an affordable price [2].

Editor
Reply to  John Hultquist
January 22, 2023 10:56 am

John ==> My grandfather’s Wisconsin dairy farm didn’t have electricity until after WWII.

John Hultquist
Reply to  Kip Hansen
January 22, 2023 12:48 pm

Indoor water? Outhouse? Sears catalogue?

Editor
Reply to  John Hultquist
January 22, 2023 3:46 pm

John ==> Hand pump, outhouses…..don’t remember the TP.

Old Man
Reply to  Kip Hansen
January 22, 2023 7:42 pm

Yup! Both sets of grandparents, one on a farm and one in a small town.

Erik Magnuson
Reply to  Kip Hansen
January 22, 2023 6:56 pm

Not even a windcharger? According to my uncle, windchargers were quite common in Montana prior to the Rural Electrification program. Gasolene operated farm plants using batteries were common in the Ohio River valley with Delco being one of the major manufacturers.

Prior to WW2, there were quite a variety of appliances that were made to run on 32VDC, which happened to be the same voltage used by most of the RR passengers cars for lighting, ventilation and A/C starting in the mid-30’s.

old cocky
Reply to  Erik Magnuson
January 22, 2023 8:42 pm

run on 32VDC, which happened to be the same voltage used by most of the RR passengers cars

So that’s why they used 32V. That’s another of life’s little mysteries solved.

Michael in Dublin
January 22, 2023 10:17 am

If one looks at the history of Africa over the past 50 years and present state of affairs – reality on the ground – it should be obvious that no sophisticated solution is going to work. What may work is using materials locally available to come up with appropriate solutions that are easy to construct and maintain. I remember seeing a charcoal cooler some sixty years ago. Porous clay vessels can also be adapted and used for cooling. In both cases these work day and night and do not depend on sunshine.

Gregg Eshelman
Reply to  Michael in Dublin
January 22, 2023 9:40 pm

Packing a small fired clay pot in sand inside a large fired clay pot, soaking the sand with water and using transpiration and evaporation through the outer pot cools the inner pot. But then you need a steady supply of water to keep the sand wet.

Tony_G
Reply to  Gregg Eshelman
January 23, 2023 9:29 am

Gregg, how cool is that able to manage for the inner pot?

PCman999
January 22, 2023 11:28 am

Sorry to vere off-topic but wtf:

“A friend uses solar power to run his fridge – 10KW of solar panels + a battery backup, to run two household fridge freezers and a freezer. Total cost about $10,000 USD of solar panels and battery – for one family of four. ”

2 fridges and a freezer for a family of 4?

How about they leave the food in the grocery stores, and only buy it when needed?

My family of four (including 2 hungry carnivores that vigorously identify as boys) does fine with one 36″ wide fridge – is it really worth it buying perishable food that much in bulk?

Tony_G
Reply to  Eric Worrall
January 23, 2023 9:31 am

doesn’t trust supply chains.

Can’t say I blame him.

As for the number of appliances, if you live fairly rural, that doesn’t seem unreasonable. Especially if you also buy meat in bulk (i.e. 1/2 cow – pretty much needs its own freezer)

bluecat57
January 22, 2023 12:25 pm

How about just getting it to oeople who would like to eat it instead of holding it hostage to polits?

Gary Pearse
January 22, 2023 12:47 pm

When I worked for the Geological Survey of Nigeria in the mid 1960s, they had a few of these in their ‘stores’. On a regional airphoto assisted mapping project of several weeks duration to upgrade a UN Project in NW Nigeria (Sokoto province), I took one along.

It was Ramadan (Muslim fast). When I met the chief of the main village, I offered to give him ice from the fridge for his drinking water after sundown. They know ice from hailstones- ‘kungkali’ in Hausa, and villages would collect a ton or two and pile a deep straw cover over it to preserve it for a few days. It was revered as a medicine for scorpion stings, stomach upset, bruises, fever …

On the appointed day, I came back from the field to a black-smoking chimney on the fridge! I had to trim the wick and, although the fridge cooled down a bit, the ice cubes were half melted. When the chief’s man arrived on foot with a gourd, I knew time was of the essence. I poured the ice cubes and its water into a thermos, jumped into the landrover with the chief’s man and drove quickly to the chief who poured the water with the last wafers of ice into his bowl and drank it blissfully.

In my experience, there is little food wasted in Africa South of the Sahara. The ignorance of ‘Sustainability Scholars’ plumbs great depths. There is a very long list of things poor Africans need before we get to solar panel operated fridges! One is refrigerators you plug in to cheap dispatchable fossil fueled power.

old cocky
January 22, 2023 12:55 pm

How about the good old Coolgardie Safe?

They aren’t especially effective, but low tech and low cost.

Another question is “what needs to be refrigerated?” Grain-based diets supplemented by vegetables when you can grow them and meat when you have some to spare are rather common.
Food waste in poor countries tends to involve rats and insects eating the grain because secure storage is quite difficult.

old cocky
Reply to  Eric Worrall
January 22, 2023 7:52 pm

Evaporative cooling doesn’t work well if the relative humidity is high.
It’s not bad in a drier climate, but refrigeration is better.

garboard
January 22, 2023 1:10 pm

hundreds of liveaboard cruisers have reasonably cheap solar/ battery refrigeration . mostly considerably smaller than typical home reefers . nothing very new here

Hivemind
January 22, 2023 1:20 pm

I think you miss the point, which is that if it works, greenies don’t want it.

Drake
January 22, 2023 3:19 pm

I have a propane powered reefer in my 5th wheel, primary power is 120v ac.

I have recently been looking into upgrading my battery system with an inverter etc. to be able to dry camp with use of the microwave and TV/satellite etc. At this point I would keep the reefer on propane while camping, at least until I can verify battery usage.

No solar panels yet since the batteries will charge from my tow vehicle while traveling and from shore power while in a RV park.

I will be able to add solar in the future, an actual not BAD use of solar. At this point I don’t want to put holes in my roof. I intend to have a portable fossil fuel powered generator for when there is a NEED for power.

I am hoping to be able to camp for 3 to 5 days on batteries alone. I don’t think my water supply will last 5 days in general anyway. I really love my wife but she sure can go through the water.

Gregg Eshelman
Reply to  Drake
January 22, 2023 9:48 pm

The 9,000 to 12,000 BTU mini split heat pumps that run on 110-115 volts AC have become popular to install in RVs and semi tractors. They’re small, rugged enough to withstand road travel, and far more efficient than rooftop air conditioners. In RV use they’re usually paired with solar panels and Lithium Iron Phosphate batteries. In a semi tractor they use an Auxiliary Power Unit which is a fancy diesel powered generator that produces 12VDC, 115VAC, heats the cab and often air conditioning, all separate from the heat, AC, and electricity from the truck engine.

So save $ and just get a 115VAC/12VDC generator and a small mini split heat pump.

Colin
January 22, 2023 4:32 pm

As a member of a Rotary club I was given a presentation by a group looking for funding for solar power for classrooms. When questioned they admitted there was an issue with batteries being unable to last in some countries in Africa due to the heat. And as a result needed to be either cooled or replaced frequently. And cooled how you might ask? Well…either by electricity generated by some of the solar panels or by diesel generators. We asked “WHAT”?

Gregg Eshelman
Reply to  Colin
January 22, 2023 9:50 pm

Dig an underground room for the batteries to keep them cool. Even in the equatorial zone a few feet down is much cooler.

stinkerp
January 22, 2023 5:43 pm

To be clear, a refrigerator and freezer don’t require 10 KW of solar panels. They require a fraction of it, around 600 to 1600 watts for both, depending on age and efficiency. Your friend has 10 KW of solar panels to power his entire home, with battery backup. 10 KW will easily power an average sized American home if you have a way to store the unused electricity. Thus the batteries, which add thousands to the cost. Over the 25 year life of the solar panels, the cost of the electricity generated is probably less than what the utility company would charge over that time if he gets a decent mount of sunshine. But the batteries increase the overall cost a lot and they have to be replaced every 5 to 10 years.

Freezers can go for hours without power, even overnight, because they are insulated, unless you open the door a lot. So theoretically a small array of four 350 watt PV panels, costing a total of $1,300 (and a power inverter costing about the same) can indeed power a modern, efficient refrigerator and freezer—and then some—when the sun shines. For 25 years or so. And more cheaply than most utilities. BUT. You need batteries for when the sun doesn’t shine for more than a day. A car battery can run a refrigerator for 5 hours or more. Two or three would probably be adequate for most periods without sunshine if you live in a sunny place.

Last edited 15 days ago by stinkerp
John Hultquist
Reply to  stinkerp
January 22, 2023 5:53 pm

I fill plastic bottles with water and keep food-free volume in the freezer occupied by ice.
The water is pure, so can be thawed and used if required.
And, of course, don’t open the door except if necessary.

Gregg Eshelman
Reply to  Eric Worrall
January 22, 2023 9:59 pm

Lithium iron phosphate batteries are much better than any lead acid, nickel cadmium, nickel metal hydride, or lithium ion type.

They can be discharged to near zero and charged (and held) at 100% without fear of damage, unlike those others.

A 200 amp-hour lead acid battery has about 100 amp-hours usable capacity before the voltage drops too much and there’s risk of damage. A 100 amp-hour Li-Fe-Po4 battery thus has the same usable capacity as a 200 amp-hour lead acid, and weighs a heck of a lot less.

Li-Fe-Po4 can also withstand more full charge/discharge cycles than the others.

But there’s a challenger to that, from out of the past, like 130 years in the past. Zinc-Bromine. An Australian company is manufacturing Zinc-Bromine batteries that work like other conventional types so it can be a direct replacement. They claim a life of at least 5000 cycles.

Another Australian company has put a lot of R&D into Zinc-Bromine redox flow batteries, intending them for use as base load backup for wind and solar, while being much safer than lithium based batteries.

Last edited 15 days ago by Gregg Eshelman
old cocky
Reply to  stinkerp
January 22, 2023 8:03 pm

A modern 450 litre refrigerator/freezer uses around 1 kWh / day. A 320 litre refrigerator uses around 600 Wh / day, as we found recently.

Our old chest freezers up the bush could handle a couple of days without power, so the much better insulated modern units should do even better.

Hasbeen
Reply to  stinkerp
January 22, 2023 10:30 pm

Insulation is the main requirement to low cost refrigeration, & to a unit holding it’s cool for long periods. I had to build in a 20 cubic Ft top opening unit into a 48ft launch we used for outer great barrier reef fishing charters to hold caught fish. It was planned to be a eutectic fridge/freezer. A top shipwright who had built similar things into ocean racers advised me how to do it.

He said to use a 4″ laminate of urethane foam made of 4 sheets of one inch foam, with alfoil between each layer. A laborious job which uses lots of contact cement. However the result was extraordinary.

We had a group of charters come up before we had time to do the piping, so stacked the thing with 18 blocks of ice, a bit under quarter full. We hoped this would last a few days & planned on flying more ice out to the boat by sea plane, along with the change of charterers. We didn’t have to. The skipper assured us they had been very careful of the ice, but I’ll bet anything it was used to chill many cans of beer as well as food, & the entire catch.

There was still a fair bit of the original ice left when the boat got back in after 12 days. We dropped all plans for compressors on the main engine, & all the pipe work, & used the thing as an ice chest for the next few years I was involved with the boat.

Gregg Eshelman
January 22, 2023 9:07 pm

Most recreational vehicle refrigerators use this system because of the simplicity. It’s easy to have three way power so they can run on gas, 12 volts DC or 110 volts AC. Gas uses a small flame while both electric modes use a small resistance heater.

Ther has also been a revolution in micro sized compressed gas cycle refrigeration. A few years ago the US military put out a contract for a very small refrigeration compressor. But then whomever ordered it canceled the order. I assume the project it was for got cut.

So the companies who put the time and money into developing the new compressors put them into production for the civilian and industrial market.

That’s where all those portable 12V refrigerator/freezers that use a tiny compressor instead of inefficient Peltier modules came from.

The compressors are so small that Adam Savage used one to build a refrigerated cooling unit he could fit in the backpack of a spacesuit costume he’s making, and it’s efficient enough to keep a person cool for hours using a lithium-ion battery.

Bill Parsons
January 22, 2023 9:11 pm

Refrigerators? Before they have reliable electricity?

Even a discussion of work-around engineering seems quaint but impractical.

The cart of consumer goods will follow the horse needed to pull it. For electricity that means fuel, generators, long delivery infrastructure and “last mile” hook ups. That technology will govern what Africa looks like in the future. Estimates online suggest that around 40% of the people in Africa have no access to electricity.

They are now where China was in the first half of the 1900’s, dreaming about the “big” (important) consumer items: a bike, a watch and a manual sewing machine (70’s in China). A decade later the “big” list had grown to five: a refrigerator, sewing machine, bicycle, TV and a washing machine.

China was electrified by the 1950s, by which time U.S. citizens had most of these things, but it took them 30 more years after their infrastructure was in place to actually be in a position to buy such goods. Now, with 100% electrification, Chinese urbanites rival our own for their wealth and consumer spending. They own cars, second apartments, take vacations in Vietnam (when Xi lets them out of their houses), and spend leisure hours on WeChat.

Cart before the horse.

Gregg Eshelman
January 22, 2023 10:09 pm

There’s a California couple who recently relocated to North Idaho. They had a successful shop doing custom work on off road vehicles, did some AirBnB rental, flipped a few houses (did one on a TV show), built and sold a shipping container house, and various other stuff, much of it they covered on their Ambition Strikes YouTube channel.

At their Idaho property it would have cost $20,000 just to bring a power line to the place. Then there would have been the costs of connecting it up plus the never ending electricity bill.

They opted to spend $50,000 on a large solar array and battery bank, big enough to power arc welders and a CNC plasma cutting table.

They recently found out just how long their system would last in constant overcast conditions. Two weeks before it shut down. But they’d planned for that with a military surplus diesel generator. In five hours the generator had their battery bank recharged, while also running whatever they were using in their house.

heme212
January 23, 2023 2:22 am

It also harms Earth’s climate by generating methane, a potent greenhouse gas. Food loss and waste accounts for 4% of global greenhouse gas emissions

yeah sure. and cows consume thousands of gallons of water. same garbage thinking. i suppose it’s a good thing rotting vegetation on the forest floor doesn’t generate CO2 or methane.

zzebowa
January 23, 2023 4:13 am

Believe me, where people are starving, there is no food waste. Zero. There are no left overs. You dont need fridges.

dragondm
January 23, 2023 10:20 pm

Many RV’s and boats have absorption fridges. The Amish also love them, they can build them in their own communities and run them off biogas. I live in a small RV, and I used one for years until the coils blew. (they rely on gravity to cycle, thus are a bit sensitive to being tilted. An occasional issue in an RV, not so much in a stationary application)

I’m currently using a 12v electric fridge, running (mostly) off solar, no less. that chews up about 300Wh of power a day. You’d need at least a 150w of solar panels and about 2.4kwh of battery to run that reasonably , You *could* build that DIY for $600-700, but you would be swapping batteries every year or two. I have 3 times that in solar and twice the battery, with batteries that will last years, and I feel comfortable leaving it run for a few days if I’m not in the RV, but my system cost $2700, and I *still* had to run the generator several times last week because it was unusually cloudy all week. Solar is very nice for the right applications, but you do have to understand it’s limitations.

Also, to correct a minor bit of incorrect info above: The mechanism of absorption fridges isn’t chemical. It’s pretty much just physical phase change. To understand how they work, imagine cooling a room with a swamp cooler. You blow air over a wet pad, the water evaporates, and cools the room. Except, now the room is humid, so you put a bunch of that desiccant crystal stuff in the corner to suck up the excess humidity. When the desiccant is saturated, you take it outside and heat it up to drive off the water. Being frugal, you put something on the pot you are heating the desiccant in to re-condense the water being driven off back into a liquid. Then you bring the re-charged desiccant back to your room, and pour the water back in your swamp cooler. Ta-DA!, you have a closed cycle. This is exactly what an absorption fridge does, except they use liquid ammonia because it freezes at a much lower temperature, so you can run a freezer. (the water in such a fridge is actually the “desiccant” for ammonia. Which is handy, since it’s a liquid, and you can circulate it past the the heat source by natural convection, without moving parts, like pumps. )

alexbuch
January 26, 2023 1:15 am

Don’t tell this any fridge making company.
They will hire a killer.

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