A $400 sun-powered absorption refrigerator can hold food at 0°F on sunlight alone — no compressor, no battery, no electricity in the loop. The blueprint was patented in 1923 by two Swedish students at KTH Stockholm. By 1957, Servel of Evansville, Indiana had sold 2.5 million silent absorption fridges in the US; two years later they were gone from store floors. Freon, planned obsolescence, and a Frigidaire ad spend that dwarfed Servel's revenue rewrote what a refrigerator was supposed to look like. This video walks through the ammonia-water cycle physics, the coefficient-of-performance math that makes solar input free at 0.7 efficiency, the three-part DIY rebuild (donor camper fridge, solar collector, chest freezer hull), the two-stage cascade that drops the box to -10°F, and the WHO vaccine cold-chain reliability proof. Keywords: solar fridge, absorption refrigerator, off-grid refrigeration, ammonia water cycle, Servel, thermosiphon, two-stage absorption. As an Amazon Associate I earn from qualifying purchases. The product links below earn this channel a small commission at no extra cost to you. Check out these survival essentials: ❄️ SMAD 1.4 CU.FT. 3-WAY RV PROPANE FRIDGE — The donor unit. Sealed ammonia-water absorption loop ready to convert to solar drive. The exact build the script walks through. https://amzn.to/49hU4Mg 🟠 1/2" COPPER REFRIGERATION TUBING, 20 FT (99.9% C12200) — The thermosiphon riser. ASTM B280 refrigeration-grade walls, the only material that survives forty years on a sealed loop. https://amzn.to/4cXh9Gp 🥶 SMARTSHIELD REFLECTIVE FOAM INSULATION — Wraps the chest hull and absorption unit. Radiant barrier + foam core, the cheap shortcut to polyiso for indoor builds. https://amzn.to/4dfhfYS 🔥 MISOL 10-TUBE EVACUATED SOLAR COLLECTOR — Vacuum-insulated tubes hit 180°F on a clear day, enough to drive the absorption loop's generator coil. https://amzn.to/4wAHoub 🎨 POR-15 HIGH TEMP FLAT BLACK PAINT — Paint your copper pipe and it pulls 95% of incoming sunlight straight into the working fluid. https://amzn.to/4wjL6I8 🎯 BULLSEYE PRECISION BUBBLE LEVEL — The absorption loop stalls if tilted more than three degrees. This $14 disc keeps the unit level on its base. https://amzn.to/4df5O3e 🔌 ANKER SOLIX C1000 POWER STATION — Grid-down backup for a small fan circulating cold air around the chest on cloudy stretches. https://amzn.to/4uDajvD 0:00 - The Buried Blueprint 0:43 - Why "Cold" Doesn't Actually Exist 1:03 - The 20% Power Drain on Your Meter 1:39 - The 1922 Stockholm Patent 2:02 - Inside the Ammonia-Water Loop 3:04 - Why Ammonia Carries 5x The Cooling 4:18 - Coefficient of Performance: 3 vs 0.7 5:01 - The Servel Collapse Begins 6:20 - Freon and Planned Obsolescence 7:55 - The WWII Aircraft Wing Detour 9:00 - Where Absorption Still Lives Today 9:39 - The $400 Salvage Build 10:36 - The Solar Thermosiphon Collector 11:19 - Chest Freezer Hull Conversion 12:10 - Two-Stage Cascade for Sub-Zero 12:52 - The WHO Vaccine Cold Chain Proof 13:30 - Safety Notes (CO + Leveling) 14:31 - Outro: $300 Pipe Under Your Yard Sources: Electrolux, "The flame that freezes" — https://www.electroluxgroup.com/en/the-flame-that-freezes-the-wonderful-box-and-a-revolution-in-fresh-food-storage-28813/ NPS, "Servel Company in WWII" — https://www.nps.gov/articles/000/the-servel-company-in-world-war-ii-the-history-of-refrigeration.htm CPSC 1998 Servel CO warning — https://www.cpsc.gov/Recalls/1998/cpsc-warns-that-old-servel-gas-refrigerators-still-in-use-can-be-deadly UNICEF, "Using the Sun to Keep Vaccines Cool" — https://www.unicef.org/innovation/stories/using-sun-keep-vaccines-cool --- DISCLAIMER --- This video is for educational and informational purposes only. It is not professional electrical, gas-fitting, refrigeration, or safety advice. Ammonia and propane are pressurized, toxic, and flammable; salvaged absorption units must be inspected for leaks before reactivation, and pre-1960 Servel-brand fridges have a documented carbon monoxide leak risk flagged by the US CPSC in 1998. Always verify legal status in your area, follow local code, and consult a licensed gas fitter or refrigeration technician before any rebuild, indoor installation, or modification of a sealed refrigerant loop. The author makes no warranty about accuracy, completeness, or safety of any product, technique, or claim presented. You assume all responsibility for any action you take based on this video. #solarFridge #absorptionRefrigerator #offGridFridge #ammoniaWaterCycle #servelFridge #propaneRefrigerator #diyOffGrid #thermosiphon #vaccineColdChain #survivalEnergy About This Channel Sketchy Survival 101 explores the physics behind survival, off-grid living, and forgotten engineering. Every video is researched using peer-reviewed studies, government data, and verified historical records. Nothing in this video constitutes professional advice. Always consult qualified professionals before attempting any project.
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He doesn't mention that ammonia is very poisonous.😊😂😂😂😂😂😂 Ammonia (\(NH_{3}\), or R717) used in industrial refrigeration is highly toxic and corrosive, posing severe health risks—including fatal lung damage or death—if inhaled in high concentrations. It is not considered a chronic poison but is an acute hazard, with concentrations of 300 parts per million (ppm) or higher immediately dangerous to life and health.
I thoughit was amonia and hydrogen
you say that they last forever but they don't, they have to continually be maintained, whether that be replacing parts or using your own labor to clean the unit. there is always going to be a cost, the frigidaire line was not about replacing it for profit sake but rather less risk, less maintenance, and the first models were meant to outlast while also getting temps down faster. You were spending less money on the electric bill than you would the propane bill while food spoilage was a lot less, which meant less food waste, saving you money 3 ways. It wasn't until the 80s and 90s that the markets decided to switch gears and sell subpar equipment in order to keep customers on rotation.
Why not use this to freeze the water tank that cools the other video with the room chiller?
RV's use these refrigerators still, propane fueled.... I never replaced one, never took time to understand them... Thank you, these were right under my smarty pants nose, and I knew I should learn about them... But was lazy, cool....
the reason we don;t have them now is safety. ammonia leak will kill people. we lose everything because of safety.
A wee bit of embellishment here.
"The Einstein fridge "- The ammonia gas absorption refrigerator that uses heat to cool were around in the 1930s/40s, You had to evacuate the house if you ever smelled ammonia leaking. People who didn't died from the gas leak. That is why they fell out of favor and are only used in commercial/industrial cooling in warehouses. (Used with ammonia detection alarms). "The Crosley Ice Ball" is the antique chest freezer that was used in the South in the 1930s because electricity was not available to all towns or farms in the South. You heat the ball over a flame for a few minutes, and then it cools your chest for about 24 hours. There isn't a cover up. It's just dangerous when the ammonia gas leaks out while you sleep at night.
Actually the compressors from back in the '50s lasted for 30 or 40 years they didn't blow after 10 years like the ones they make today.
I appreciate your attempt to provide some real good information. But, you got sidetracked on selling the idea. Let me tell you what. Not of my phone.
Sketchy video.... Among several things you've done is inflate the death rate of compressors and early model refrigerators. As a former & retired HVACR tech several units 70+ years old are still running to this day. The main problems with them is moving the refrigerator too often, ice picking the coils and those locker door handles that killed several children over the years. Concerning the absorption units. The better way to heat them (though many come with a gas/electric option) would be photovoltaic "solar-powered " panels along with battery & an inverter for house hold voltage . For less than $500.00 one could power the unit indefinitely. Optional too would be the 12 volt heat element type absorption units (that typically run off a campers vehicle 12 volt system) and widely available today. The only drawback is if that configuration is solar powered no batteries are needed but when there's no sun shine propane would be needed.
Interesting, but a little simplistic. I own 2 Servel absorption fridges dating from 1936. They both run and are in use. i"ve done quite a bit of work on them, replacing the cold valve on one and the burner on the other. The carbon monoxide issue you mention is easily handled by proper maintenance of the unit - if the flues are kept clean and the flame properly adjusted, they are no more dangerous than a gas stove. As to your conversion, it is interesting but I expect more involved than you present. The fact that you don't show any photos of an existing conversion makes me suspicious. Wrapping copper tubing around the coil of a existing absorption system may be a little harder than in the line drawing. Worth a try but anyone contemplating a build should be prepared for setbacks. One other correction: Servel was not the only American absorption cycle manufacturer. There were numerous others, including Norge.
The absorption fridge should be refined now using Lithium cells and solar panels to power the heat source.
Quite a bit of misinformation but the general theory holds true. i.e. 11:00 stating that the collector works on "any clear day above 40 degrees", not even true. Doesn't matter based on ambient at all if your insulation is good and the sun is shining.
6:15 This is one of those concepts that sounds almost futuristic, but the way you explained the science behind it makes it surprisingly believable. Using the sun to create long-term cooling instead of just heat is such an interesting shift in thinking. I really like that you focused on the physics and principles instead of just the claim itself. Definitely a video that sparks curiosity and makes people rethink energy and food storage ☀❄👍
Absorption refrigerators do in fact die. The expansion and contraction eventually wears out the copper lines. If you have that fire going and that ammonia leaks the whole thing catches on fire. Next, the reason people get rid of their Dometic and Norcold is because they suck. Norcold has been called "Nevercold" for years and years. Ask anyone with an RV.
So basically you'll need a propane gas tank to "power" it up.. which will cost money.. or if you'll go with the solar option, you'll get heat from the sun. What happens on cloudy days or in the winter when the temperature drops near or lower than freezing point? If you're on solar, what will be the heating catalyst for the fridge to run? Thanks
9:20 ما دامت ثلاجات الإمتصاص لا تزال تصنع من قبل شركة DOMETIC و NORCOLD وستة شركات متخصصة أخرى، فلماذا تنصح في الدقيقة 10:10 بشراء ثلاجة مستعملة؟، لماذا لا أشتري ثلاجة امتصاص جديدة من تلك الشركات الثمانية التي لا تزال تصنعها؟، ولماذا لم تذكر أسماء الشركات الستة المتخصصة الأخرى لتكتمل قائمة الشركات الثمانية التي يمكن من خلالها شراء ثلاجة امتصاص جديدة؟
Does anybody sell these?
Did your grandparents have a silent gas fridge in the kitchen, or had your family already switched to compressors before you were born? For reference, Servel sold 2.5 million absorption fridges in the US between 1927 and 1957. Whirlpool bought the Evansville plant in 1958 and retooled it for compressors within six months.