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A new air-conditioning system manages without nasty gases
- haspoken 5y agohttps://archive.is/y4OwA https://archive.is/y4OwA
- KaiserPro 5y agoYou can use propane for the refrigerant. The halflife in the atmosphere is pretty short. Its cheap, non toxic and fairly well understood. In the EU/UK it also has the advantage of not needing a license to install yourself. Obviously this new technology is important, but its not here now.
- throwaway0a5e 5y agoRational people turn into tantrum throwing toddlers and absolutely go crazy if you suggest using a flammable hydrocarbon as a refrigerant (never-mind that many refrigerants are already flammable hydrocarbons or nasty in indoor spaces to the point where propane isn't worse).
- Animats 5y agoBefore freons, ammonia was used. Getting rid of ammonia refrigerants was considered a big step forward.
- cartoonworld 5y agoIn large commercial applications ammonia is still commonly used. Getting this crazy crap out of our homes and stuff is indeed a big step forward, though
- kenmacd 5y agoidk. I'd be happy to run ammonia at home. When I looked years ago no one make small enough compressors though.
- userbinator 5y agoAmmonia was never used in home refrigeration, except in absorption units (where it is still used today); the other toxic one that was widely used is SO2 (sulphur dioxide).
- KaiserPro 5y agoto be fair I was a bit sceptical about it when I first put it in. Its pure, rather than having the tell-tale smell. So I was a bit worried about silent leaks. However as you point out, some other refrigerants are pretty flammable, or otherwise generally a bit shit for your health. Also, in my unit, there is something like 66grams, although I suspect 10 grams of that was bled off to purge the lines of air. So if there was a slow leak, its unlikely to persist for long, or cause an explosion.
- Gibbon1 5y agoEvaporated I think 66grams of propane is about 1cuft of gas. which doesn't seem to me to be that scary. A perfect air to fuel ratio would require mixing 16 cuft of air. And flammable range is narrow. Comparison, your kitchen is probably 1000 cuft. So I think you are right, slow leak isn't much of a hazard.
- ashtonkem 5y agoA typical natural gas range probably releases more than 66g of unburnt hydrocarbons into your home.
- userbinator 5y agoNatural gas is basically methane, which is around 16g/mol. 1mol of gas at STP is 22.4L, so 66g of methane is around 90L. A typical gas range has a flow rate of a few cubic meters per hour, or a few liters per minute. So just to get 66g of unburnt gas released, you'd need to leave a burner un-ignited for most of an hour, or considerably longer if it was burning.
- KaiserPro 5y agothis is true, but it stinks, so you know its doing it. If there was no added smell, I could easily leak 66 grams into the house without knowing.
- tgsovlerkhgsel 5y ago66 grams of propane are 35.1 liters. The lower explosive limit is 2.1%. So if the content leaks out slowly enough to mix with at least 2 cubic meters of air, it's going to be fine. However, if it leaks a bit more quickly, I can totally see it creating an explosive mixture in the space behind your fridge (or inside), to be ignited when the compressor/light switch trigger next. I can see why people aren't super happy with the prospect. A stoichiometric mixture forming inside your fridge and blowing up when you open it would definitely ruin your day.
- userbinator 5y agoPeople remember things like this: https://en.wikipedia.org/wiki/Cocoanut_Grove_fire https://en.wikipedia.org/wiki/Cocoanut_Grove_fire edit: please READ the article before you think of downvoting.
- ashtonkem 5y ago... which had absolutely nothing to do with refrigerants.
- nzgrover 5y agoThis one did: https://en.wikipedia.org/wiki/Tamahere_coolstore_fire https://en.wikipedia.org/wiki/Tamahere_coolstore_fire
- userbinator 5y agoI know the article is lengthy, but did you even try to search for refrigerant or freon in it? The air-conditioning also used flammable gas, because Freon was in short supply
- deleted 5y ago[deleted]
- ashtonkem 5y agoWhich wasn't determined to be a source or contributor to the fire. > The Boston Fire Department investigated possible causes of ignition, the rapid spread of the fire and the catastrophic loss of life. Its report reached no conclusion as to the initial cause of ignition, but attributed the rapid, gaseous spread of the fire to a buildup of carbon monoxide gas due to oxygen-deprived combustion in the enclosed space above the false ceiling of the Melody Lounge. The gas exuded from enclosed spaces as its temperature rose and ignited rapidly as it mixed with oxygen above the entryway, up the stairway to the main floor and along ceilings. The fire accelerated as the stairway created a thermal draft, and the high-temperature gas fire ignited pyroxylin (leatherette) wall and ceiling covering in the foyer, which in turn exuded flammable gas. Yes, they used flammable gas in the AC, no that was not determined to be a source or contributing factor to the fire.
- s0rce 5y agoThey sell them in appliance stores now, most people wouldn't even know, it's called R290. My fridge used it, sadly it died and was replaced with a conventional refrigerant model.
- blibble 5y agothey seem concerned about labeling it as propane the one I bought had "R290 ECO-FRIENDLY REFRIGERANT" all over the box, with the chemical name nowhere to be found (of course I immediately wanted to know what R290 was and googled it...)
- mannykannot 5y agoNot to mention that gaseous hydrocarbons are widely used within homes, and not in hermetically-sealed devices either, as would be the case when used in a heat pump.
- epistasis 5y agoWhat, you mean this methane spewing stove that causes really bad air quality, and is no more responsive than an induction stove and far less powerful than an induction stove? "Cooking with gas" is great marketing, but not so great in reality unless it's an outdoor wok.
- xeromal 5y agoCan't say I have a good reason why, but I HATE cooking with an induction stove. Just not interested in learning how to manage heat. OOGA OOGA, I do understand fire.
- kube-system 5y agor1234yf is already in wide use. It a little bit expensive, but it does not pose the global warming concerns of HFCs, doesn't deplete ozone like CFCs, and isn't as flammable as hydrocarbons. https://en.wikipedia.org/wiki/2%2C3%2C3%2C3-Tetrafluoropropene https://en.wikipedia.org/wiki/2%2C3%2C3%2C3-Tetrafluoroprope...
- marcus0x62 5y agoR1234YF is ridiculously expensive compared to R134A, like 10 times the price. (For reference - I can buy a 10 pound cylinder of R1234-YF on eBay for $500. A 30 lb cylinder of R134A is $150 - $200.) It is also takes more expensive equipment and a significantly longer amount of time to charge a R1234-YF system. All around, it is a terrible refrigerant for an end-user.
- userbinator 5y ago152a is another cheap alternative, and can even be bought without any license, at least in the US - it's the gas in "gas dusters". While 134a operates at a higher pressure than 12, 152a is a close match and works well as a replacement for old R12 systems.
- tdeck 5y agoHere's a guy who recharged an old fridge with propane: http://www.sparkbangbuzz.com/els/refrig2-el.htm http://www.sparkbangbuzz.com/els/refrig2-el.htm
- s0rce 5y agoMy old fridge used propane from the manufacturer, sadly it only lasted a few years and repair was more expensive than another one. The new one uses a more conventional refrigerant.
- userbinator 5y agoNote the buildup of frost on the return tube all the way to the pump. That's a clear sign that you've massively overcharged it! I agree with his position about environmentalists, but I think he should at least learn a bit more about the science first. YouTube can help: https://www.youtube.com/watch?v=lLauVofEDzY https://www.youtube.com/watch?v=lLauVofEDzY (All the refrigerant should boil off in the evaporator, and the return out of the cabinet should contain only room-temperature vapor. Frosting all the way back to the compressor wastes power cooling what doesn't need to be cooled, and can damage the compressor with liquid refrigerant.)
- throw0101a 5y ago> You can use propane for the refrigerant. Used in medical/scientific freezers that go down to -80C: * https://www.thermofisher.com/ca/en/home/life-science/lab-equipment/cold-storage/lab-freezers/ult-freezers/models.html https://www.thermofisher.com/ca/en/home/life-science/lab-equ... A combination of R290 (propane) and R170 (ethane) + R290 mix.
- throwawayboise 5y agoA mix of propane and iso-butane can be used (perhaps illegally, depending on where you are) as a replacement for old R12 refrigerant.
- frosted-flakes 5y agoConfusingly labelled as R12a and sold under brands such as RedTek. This is the only type of refrigerant available to unlicensed consumers in Canada, and it is widely available in stores everywhere. R134a is not sold in stores here. The US is the opposite—R134a is available to DIYers everywhere, but R12a is banned because it is flammable.
- jeroenhd 5y agoMost portable air conditioners I've seen use "R290" (propane) as a coolant, both from expensive brands and budget brands. I'd say propane is very popular in that industry, it's not just an option. Of course, there are some risks to using propane (which is why these devices come with warnings not to store them in small rooms) but I suspect many people will already be using propane cooling somewhere without even knowing.
- fettucini 5y agoKaiserPro says >"You can use propane for the refrigerant. The half-life in the atmosphere is pretty short. Its cheap, non toxic and fairly well understood."< Also pretty fucking explosive. Propane, when released, flows to the ground and seeks the lowest level. Unlike natural gas (which rises), propane settles in valleys, nooks and crannies and waits for a spark. www.bing.com/search?q=propane+refrigerant+explosion Propane has been tested and, in the past, rejected as a refrigerant for these reasons. Once again, the fools of industry make another attempt to roll back nature to save a few dollars. We won't see the end of this until a few Whole Foods Stores and convenience stores explode with large number of deaths, whereupon the U.S. gummint will step in and say that they didn't mean it all along, that propane should never be used as a refrigerant and that industry is to blame. I'm not stepping into another Whole Foods Store until well after this entire R-290 refrigeration scheme blows over (or better said, blows up): https://bpnews.com/feature-articles/propane-refrigerant-whats-not-love https://bpnews.com/feature-articles/propane-refrigerant-what... Is R-290 (refrigerant composed of CO2 and propane) flammable/explosive?: https://www.bing.com/search?q=r-290+flammable https://www.bing.com/search?q=r-290+flammable
- matmatmatmat 5y agoWish they had mentioned the efficiency and how it compares to existing options. Anyone know?
- Animats 5y agoNo idea. Nitinol heat engines are available in toy-size.[1] There used to be interest in shape-memory alloys as robot actuators, but they're slow and need too much power. It takes too much heat to generate mechanical motion. Does that mean it has high heat pumping capability, since refrigeration is the inverse of a heat engine? I don't know. [1] https://www.imagesco.com/articles/nitinol/09.html https://www.imagesco.com/articles/nitinol/09.html
- laurencerowe 5y ago> Tony Ennis, Exergyn’s chairman, reckons this method of cooling is not only more environmentally friendly than an HFC set-up, but will also be less expensive to buy and 30-40% cheaper to run. Not absolutely clear, but the cheaper running cost implies it uses less electricity than existing options.
- Waterluvian 5y agoSay there’s a hypothetical AC that works very well and requires no environmentally problematic materials and lasts forever, Does the simple act of moving heat from inside to outside do any measurable, meaningful harm to nature?
- throw0101a 5y ago> Does the simple act of moving heat from inside to outside do any measurable, meaningful harm to nature? It would still take energy to run. How is/would that energy produced?
- Cthulhu_ 5y ago> Does the simple act of moving heat from inside to outside do any measurable, meaningful harm to nature? No, the heat moved is trivial compared to the heat coming in from the sun. That said, urban design (concrete, asphalt, etc) that absorbs a lot of extra heat will have a noticeable effect, definitely on a local level. Cities with a lot of green are a few degrees cooler as well, in part because of shade (the heat is captured higher up), in part because of evaporation.
- BayAreaEscapee 5y agoNo air conditioner is going to be 100% efficient. You're still going to consume a fraction of the heat energy being transferred from indoors to outdoors. Unless your home is powered by 100% green energy, you're still indirectly adding carbon to the atmosphere.
- Scipio_Afri 5y agoEven if its 100% green energy - which don't get me wrong is orders of magnitude better for warming of the planet - it still contributes to warming of the earth. You're taking some wavelengths of light that would normally be absorbed by say plant matter (thus using that energy to pull CO2 out of the atmosphere) over an area and/or some wavelengths simply reflected out to space without being absorbed by the solar panels (which definitely are designed to absorb as many wavelengths as possible). Then energy conversion from DC to AC and to transmissions lines to where its used all have losses which is energy dissipated in heat form. So the conversion process there can cause heating as well. Certainly better than combustion which creates heat AND creates gasses which trap that and other radiation as heat.
- kensai 5y agoA similar amazing technology has been recently shown at a Fraunhofer Institute in Germany. And the magnetocaloric approach sounds even more promising! https://www.ipm.fraunhofer.de/en/press-publications/press-releases/electrocaloric-heatpumps-refrigerant-free.html https://www.ipm.fraunhofer.de/en/press-publications/press-re... https://www.youtube.com/watch?v=6tKtc0cHrUg https://www.youtube.com/watch?v=6tKtc0cHrUg
- TomatoDash 5y agoBoth the Economist's text and the Fraunhofer press release focus mostly on the benefit of not using certain refrigerants. But for in home AC use noise reduction might be a much stronger selling point. Especially in Europe where it is common with so called portable indoor AC units that put the noisy compressor inside the room you want to cool down.
- MrStonedOne 5y agorubber band fridge: https://www.youtube.com/watch?v=lfmrvxB154w https://www.youtube.com/watch?v=lfmrvxB154w same concept, less refined.
- b0rsuk 5y agoThe Revenge of the Circulating Fan https://www.lowtechmagazine.com/2014/09/circulating-fans-air-conditioning.html https://www.lowtechmagazine.com/2014/09/circulating-fans-air...
- mlwiese 5y agoYou can use CO2 as a refrigerant. Non flammable and enables heat pumps to be practical at lower temperatures. Lots of products on the market. See https://r744.com https://r744.com
- tgsovlerkhgsel 5y agoI assume using it results in a less efficient system though, right?
- namibj 5y agoRuns at high pressure, can be quite efficient though, iirc.
- GuB-42 5y agoI don't know about efficiency but the pressure is much higher, making the system much more expensive.
- userbinator 5y agoPeople experimented with CO2 refrigerant around the end of the 19th century, when refrigeration had just been invented and most other refrigerants hadn't been invented yet; it was called "carbonic acid" and required much heavier machinery due to the high pressures. (Typically over 1000PSI for CO2, compared to 100-200PSI for HC, CFC, and HCFC.)
- nanomonkey 5y agoStirling engines can be run in reverse to act as a heat pump. In fact, I have a two 25 liter coolers that utilize Stirling engines, they run silently and cycle between using 5 and 33 watts, averaging about 11 watts once the components the contents have settled on the 4 C set point. Curious if anyone has looked into utilizing larger ones for cooling buildings.
- tgsovlerkhgsel 5y agoWikipedia: "At typical refrigeration temperatures, Stirling coolers are generally not economically competitive with the less expensive mainstream Rankine cooling systems, because they are less energy-efficient."
- nippoo 5y agoR32 (difluoromethane) or R290 (propane) both have ozone depletion potential (ODP) of 0 and are in common use with new refrigeration units. This technology looks interesting due to its simplicity and could potentially be cheaper than existing phase-change systems which are prone to leaking and need maintenance. But refrigerants which don't directly harm the ozone layer are already here...
- jjeaff 5y agoAnd propane has close enough properties to r21 that it can be used as a drop in replacement. Of course, HVAC guys flip their lid at the thought of it. Because they want to get that sweet markup on the extremely expensive, discontinued r21 or a pricey alternative.