Emissions free cooling. Can we do it?

By 2050 there will be almost six BILLION air conditioning units in operation around the world. Current technology is extremely energy hungry and often uses refrigerant gases with very high global warming potential. We can't eliminate air conditioning, because millions of people would literally die. So what are we doing to try to solve a rapidly worsening problem?
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Research Links
IEA - The Future of Cooling
www.iea.org/reports/the-futur...
Transaera
www.transaera.com/
Blue Frontier
bluefrontierac.com/
Zephyr
www.zephinc.com/
Metal Organic Frameworks
www.aiche.org/sites/default/f...
Check out other KZbin Climate Communicators
zentouro: / zentouro
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Kurtis Baute: / scopeofscience
Levi Hildebrand: / the100lh
Simon Clark: / simonoxfphys
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Beckisphere: / @beckisphere
Our Changing Climate : / @ourchangingclimate
Engineering With Rosie / engineeringwithrosie
Ella Gilbert / drgilbz
Planet Proof / @planetproofofficial
Our Eden / @oureden

[@AlRoderick]

The benefit of using a desiccant-based system is that you can dry out the desiccant solution using heat instead of electricity, which means that you can use a source of waste heat or solar thermal which can be generated more efficiently than solar PV, or even in parallel with it. One solution I've seen for incorporating desiccant loop cooling with a refrigerant cycle cooling is to use the waste heat from the refrigerant cycle to dry the desiccant.

[@Yavorh55]

If you have two containers for desiccant you may not even need downtime to dry it - just hot-switch which container is being used and pump waste heat round the other one to dry it out in the meantime

[@nathanielstephenson7932]

​@@Yavorh55something like that might work, but these systems are a bit more involved and interconnected than they are made out to be. I looked over a flow chart of one and there were different concentrations, temperatures, and humidity all over the place. I don't understand the process well enough to say for sure, but by the time this method was put into place it could end up being indistinguishable from having 2 whole units side by side sharing a fan... I'll take another look, but I was tired and didn't have much time when I first glanced, let's hope I just took the wrong conclusion.

[@abcdjhffkuggf]

I want to buy something like that so badly. Where I live the temperature and humidity are both in the eighties year round (30 C for folks outside the US.)

[@inquaanate2393]

This relies on being able to dry out the desiccant in a humid environment aka, not possible.

[@communitycollegegenius9684]

@@inquaanate2393 You are correct. If you could use heat to dry the desiccant then the desiccant to cool your house you would have invented perpetual motion. It is NOT the "heat" that dries stuff, but the cold-side of A/C that is lower in humidity. Dave made an historical error that is important to understanding this problem. Mechanical compression A/C was NOT invented to cool per se, but to dry ink onto newspaper. The first block diagram he showed used a heat-pump to dry the desiccant. This does work right now. But they use the heat-pump as a de-humidifier. The complexity is WAY to much for home cooling.

[@stevesmith-sb2df]

I live near the Gulf of Mexico so removing water vapor from the air is always needed. When the indoor humidity drops below 50% you can be comfortable at a higher air temperature.

[@mikedavison3400]

I live in the Pacific Northwest on the coast. We are lucky in one sense that we need dehumidification only during the cooler months. I hear from people time after time that the damp bothers them far more than the cold here. I’m a big proponent of using a dehumidifier here and the heat it pumps out is considerable which is a win win. Our situation near the coast is a minority one though and these new what I would call hybrid types of technologies will be progress where heat and humidity happen at the same time.

[@MrARock001]

Interesting tidbit of information: the first air conditioners were invented specifically to dehumidify the air in factories where heavy machinery was releasing too much moisture and spoiling products (worker comfort was just a happy coincidence). That's why we all call them air conditioners instead of air coolers.

[@clivemitchell3229]

If there were two stores of salt, one could be dried by solar heating while the other is being used to cool during the day. There's usually a lot of solar heat around when the weather's hot and plenty of uses for electricity at night.

[@misterbum1]

I have been a viewer of your videos for an extended time, and have not supported you. I just changed that by joining your funding mechanism. Thank you for all of the information that you share with all of us around the world, and for your intelligent, civil, and informed presentations that make it possible for those of us with no heads for science to understand the issues you present.

[@JustHaveaThink]

Thank you so much. I really appreciate your support :-)

[@BaronVonSTFU]

I don't know how different this new solid material is from silica, but Munters makes commercial dehumidifier units that already use this same principal . They've existed for years. Walmart and Target here in America use them. They still use tons of regular dx systems though. It also adds complexity to the system and a lot more maintenance. The old units used to use gas heat exchangers that ran all year to dry out the desiccant wheels. The newer ones use a regular compressor that has a vfd on the condenser motor. It uses the heat of a specialized condenser to dry out the saturated wheel. The wheel then spins and is exposed to the unconditioned air to remove more humidity. The wheels last for years and years but they must be cleaned because they get clogged with dirt. We also just run into skill level problems with techs. These units have been around for years but people still don't seem to understand how they work.

[@grahamrutherford8800]

Excellent, I love it when clever people find an innovative way to supercharge existing technology. Bravo!

[@JustHaveaThink]

Glad you like it!

[@SunriseTequila523]

​@@JustHaveaThinkPlease make longer videos, I wait for your weekly video every time and it's a pity that they are just 10 minutes long haha. Plus you have a great reassuring and relaxing voice which is also a huge plus. Keep up the awesome work Dave

[@L0615T1C]

how is your comment 1 day old when the video was released 10 hours ago

[@TheLosamatic]

@@L0615T1Cpatreon

[@grahamrutherford8800]

@@L0615T1C Maybe Patreon supporter preview.

[@justsayen2024]

I've been in this field for 35 years plus and when I have installed air conditioners, immediately the customer feels cooler although when you look at the thermostat it hasn't dropped one degree because the first thing they are conditioner does is take the humidity out of the air and if you live in a place like South Carolina or Florida you know what I'm talking about. Very interesting innovation although it has to be affordable in order to be adopted.

[@sjsomething4936]

Definitely has to be affordable, hopefully even if it costs more up front the long term energy savings would sell it. However, that argument isn’t going so well for EVs which makes me doubtful that it would be any different for AC units. Companies (especially big ones) will always run the lifetime cost numbers and convert if it makes sense, this is not as likely on the individual level. However, even getting companies to convert is a win in terms of total energy consumption, and once companies have adopted the technology it could both drive prices down and possibly change public perception.

[@wobby1516]

Even over the pond we notice the difference between a hot dry day and a same temperature humid day definitely reducing the humidity make thing way more comfortable. 🇬🇧

[@nagualdesign]

​@@wobby1516 That's because we're the same species, believe it or not. 😉

[@jamesvandamme7786]

@@nagualdesign I'm ... not totally convinced.

[@nagualdesign]

@@jamesvandamme7786 😋

[@fredygump5578]

My idea is to use a geothermal loop for cooling and heating. The liquid from the geothermal loop may be enough to condense moisture on it's own, and using the cold side of a heat pump can provide more cooling if needed. In climates that need heating and cooling, this would seem to "store" heat underground in the summer, and then the heat is recovered in the winter. On the surface it seems this might increase the efficiency of geothermal heating while providing efficient cooling.

[@ch94086]

Liquid dessicants have been around for a while, but seems like a good concept. A tank of dessicant is energy storage, as you note. The liquid dessicant systems I've seen use solar heat not night heat pumps to dehydrate. Kind of a different way to use solar heat.

[@Yattayatta]

Love your channel, always realistic takes on new things, no doom and gloom and no over enthusiasm, just the way I like it. Keep up the good work!

[@Tore_Lund]

Just building houses more wisely, could abolish the need for active cooling entirely in most places.

[@ThatOpalGuy]

for now, certainly.

[@BasilBear]

It's going to be very , very long time before everyone is living in a better building.

[@Richard-iq8xb]

It would only do that for the new houses, not existing ones (unless you propose replacing all current houses, which would have a significant impact on emissions). So while better building standards should be introduced, there will still be a need for active cooling.

[@MarinusMakesStuff]

Your plan would then also involve demolishing the old buildings. And as you may know the new rules already make it extremely hard to build new buildings due to emission budgets etc, etc. We are royally doomed.

[@sjsomething4936]

I’m 100% in agreement that construction techniques and technology can make massive improvements, in most areas of the world it would eliminate 90%+ of heating and cooling needs. However, I’m not entirely certain that building more wisely will solve all of the cooling issues in the hottest parts of the world, although people in those places are already very acclimatized to the heat so even a small drop from say 38C / 100F degrees to 32 / 90 would be a real improvement. Combined with efficient air conditioning we could likely save 90% of the energy currently used to control indoor temperatures. As some other posters have noted, building codes need to be updated to permit or better yet enforce more energy efficient buildings, which is an uphill battle. People already pay a lot for homes / housing and the industry itself is highly resistant to change as well as price sensitive. Given the amount of money the construction industry spends on “lobbying” (aka bribing) politicians about policy and how to vote, I suspect change will come about incredibly slowly. At an individual level, it can certainly be done, the house that Matt from the channel Undecided with Matt Ferrell had built was quite remarkable, and hopefully his neighbours see what’s possible and others who watch his channel will consider doing similar. Personally I’m about to embark on upgrading our 115 year old house to have much better insulation etc, but I have to determine how to keep some of the legacy, character aspects of the house such as tremendous imperfect windows with bubbles and swirls yet still have a very energy efficient home. Unfortunately it will be a lot more expensive to retrofit than simply building efficiency in from new, which is another big challenge for existing homes.

[@j_razavi]

Very happy to hear about MOFs being used! One of the most exciting kinds of upcoming tech in my opinion!

[@arthurhamlin6594]

When I heard the phrase "reviewing the archive", I was hoping for updates on companies, products and projects that had been featured on the channel a few years ago to see if they were any closer to success. Hearing about newer entries to the field just feels like kicking the can down the lane as it were.

[@FightingTorque411]

He is still doing what you suggest as well from time to time

[@davidmead6337]

@@FightingTorque411 WE all need to push for unilateral and world wide financial action for energy alternatives, and stop the fossil fuel industry at the same speed, without destroying both the earth and our civilisations.

[@ericpmoss]

Love the video. Reduce > Reuse > Recycle.

[@jimhood1202]

Exciting times. Thanks for keeping it positive Dave.

[@jimadams6159]

Really interesting as always. I think I have said it before but the way you explain each subject you talk about is brilliant, so clear and not condescending.

[@fixeroftheinternet]

Well done Dave. You cover the really important but less glamorous technnologies to get on us on the road less travelled towards a fossil free energy world. Keep.up.the great work!

[@martyschrader]

Spot on about combining technologies. It's the only way.

[@paulohlstein2236]

Thanks for this episode. Was totally unaware of the developments you covered.

[@jaredleemease]

Than you David. 😎

[@mikedodger7898]

Very useful Rob. Thank you.

[@mylesrussell]

Amazing research as always!!😊

[@Yanquetino]

Cool, Dave! Literally.

[@Bassillixx]

I run a dehumidifier, and it's a great provider of distilled water !

[@lizsteilkie]

The only tech guy who does updates. Love it.

[@punditgi]

Just Have a Think does it again! Massive thanks for this highly useful information! 🎉😊

[@leemason4024]

Thanks for another great video!

[@danielabetts]

Excellent video, fantastic explanation! Thank you.

[@erininnes7448]

It's frustrating how much time we spend talking about making heating and cooling "more efficient," and how little we spend talking about changing OUR BUILDINGS, so they don't need to constantly expend energy to heat and cool themselves. Vernacular architectures had this figured out centuries ago.

[@MarkkuS]

Fixing old homes releases mote co2 than it saves..

[@vylbird8014]

People want their giant sun-facing expanse of glass.

[@sailawayteam]

So true.

[@waqasahmed939]

Definitely. Making your house more in line with PassivHaus principles seriously reduces your requirement to have AC in the first place.

[@waqasahmed939]

@@MarkkuS Not really. PassivHaus principles seriously reduce the amount of energy you require year on year

[@jlopat]

love your program

[@roysigurdkarlsbakk3842]

Thanks a lot - this was highly interesting :)

[@OAK-808]

Great. Thanks for all he info.

[@jamessellards7157]

Love this channel

[@TheQsam1]

As always a great video:) love the throwbacks

[@tecsolint]

Brilliant like always !!!

[@beautifulgirl219]

Thanks mate. Cheers. :)

[@badrinair]

Thank you

[@l0I0I0I0]

The company can at times eliminate energy to dry desiccant with the following improvements. If they double the desiccant and dry half during the heat of the day, while using the other half for dehumidifying, solar can dry the desiccant which will be used for the following day thus reducing or at times eliminating energy needed to dry the desiccant. Energy storage can eliminate the need for energy. Low solar days can be offset with what they are currently doing using power to dry it or eliminate with heat storage.

[@andreavaleri0]

Thank you for listening to the comment I posted some time ago. I am confident that I am not only one to have asked that. Thank you ❤

[@Snodgrassdsd1]

Thanks!

[@martincotterill823]

Great video, Dave, and an interesting solution.

[@JustHaveaThink]

Glad you enjoyed it

[@bigfishoutofwater3135]

The ability to control humidity independently of heating and cooling can increase comfort and use less energy but it might have higher equipment costs. For this tech, it would nice to have a humidity set point and be able to control how much supply air bypasses the desiccant. In a hot but dry climate like a desert the extra moisture in the air might actually be a benefit. I do like the idea of using a heat exchanger when you don't want the extra moisture though.

[@emceeboogieboots1608]

This is pretty fascinating! The transformation of the energy markets is a great lever to make these sorts of ideas take hold. Moving some cooling load off peak is a great idea Onya Dave, thanks for keeping your reporting up to date👍

[@johnkelly3886]

I live in Johannesburg (high hot and dry). Evaporative cooling works very well for me. I don't know why so many buildings use large expensive conventional air conditioning systems.

[@incognitotorpedo42]

Humidity is evil. It causes mold and mite problems, can lead to building damage, and makes people uncomfortable. Evaporative coolers are a perfect breeding ground for pathogens, some of which are very dangerous. These are probably the reasons people choose conventional AC in most locations.

[@johnkelly3886]

@@incognitotorpedo42 In the coastal zone humidity is a problem. Up on the Highveld (a high semi-desert interior plateaux) a bit of humidity is very welcome. The only mould problems we have is from leaving food too long in the refrigerator. I do worry about the water in my evaporative cooler. I wash the reservoir with disinfectant and replace the water once a week.

[@Themanincumbent]

You can use most modern air conditioners as heaters aswell as they just reverse the process. In fact I find it strange that air conditioner= bad and air source heat pumps= good when they are both basically the same device. I installed an air conditioner on my house in the uk in a bedroom. On the rare days I use it I can leave the bedroom door open and it cools the whole house. I suffer from allergies and the air conditioner has a de-ioniser which helps keep the air clean( main reason for buying it), so I run just the fan most nights. In autum and spring I can set it to heat to put some heat in the house without having to run the gas boiler. I find it very cheap to run as my electricity consumption over a year has not changed much. I have friends that have adopted solar and heat pumps, and none of them are happy with the outcomes that have here in the uk. In fact a good friend who has had solar for 10 years has just been compensated as the savings were no where near the projections of the installation. While it’s nice to see people consuming lots of energy developing new ideas to get us to consume even more energy, I myself believe you should just consume less in every aspect of your life to reduce your individual impact on the planet. Climate change or whatever we want call it is simply the result of overconsumption of the planets resources and all the ideas I have seen simply move consumption from one resource to another and introduce more inefficiency which results in net increase of resources which will eventually create more problems even if we can’t see those problems yet. If we were smart enough to see how our efforts effect the future then we would not have the problems we have today, which is the rub. Makes you think?

[@veganislandradio9957]

Cheers Dave. Once again an insightful little nugget. Keep them coming please. 💖✌💖✊💖

[@jfjoubertquebec]

Wow! That's great!!

[@floydbertagnolli944]

Yea!!! Another SOLUTIONS video! Well done. 😊

[@user-yx6xk8of8o]

😘Kisses to you my friend I'm glad you have been able to concentrate on Just have a Think.... thanks Jack Conte!

[@stevewaugh2191]

Fantastic.

[@cesardeleon3856]

Gracias

[@arleneallen8809]

Good subject matter and research in your videos. Discovered you on Robert's channel some time ago. I appreciate the knowledgeable background - the exact opposite of the so-called influencers. The more intellectual stimulation, the better. I learn something every time.

[@vicbauwens]

There is an ironic effect going on in temperate climates. I live in Belgium and like many people we have recently installed PV panels, which produce way more electricity than we consume during the summer months, and much less over the winter months. With the value of the surplus electricity injected into the grid being almost zero, I decided to install an AC unit to cool the house with excess energy. Previously we never had an AC unit and strictly speaking we don't need one since we only have a couple of unbearably hot days every year. So yes, AC devours energy, but in our case it's carbon free energy. Am I part of the solution or part of the problem?

[@macmcleod1188]

Well, basically you are creating more heat in the environment than you are removing. To cool your house 5 degrees, you create a house worth of air that is 6 or 7 degrees hotter. I'd look into insulation (tho I'm unclear how dirty making insulation is) and that superwhite paint to reflect the light and heat back into space. And of course use the ac on the unbearably hot days.

[@barrycarter8276]

You do realise that you’ve become part of the sustainability problem. Every Air Conditioner added to the system yours or the Grids is at the expense of minerals and use of FINITE Flammable Fossils (FFF’s) from the mining to the production of the components that form that AirCon, and the more technologically complex it is the more FFF’s is consumed, and if your think the efficiency can take care of that, think again as Jevon’s Paradox: Fuel efficiency gains tend to increase, not decrease, fuel use. And we are looking towards sustainability and not a short term fix, aren’t we🤔

[@christinearmington]

Bravo! 🤩

[@SonnyDarvishzadeh]

​@@barrycarter8276in next couple of years, heatwaves will take significant number of lives. I'm tired of hearing "you become part of the problem by installing AC" while I no alternative solution is proposed. I moved to Germany 6 years ago, the 2 weeks only heatwaves have now become 3 separate heatwaves from 1 week to 2 weeks. Summers in Europe are getting as hot as middle eastern countries. It's very hard to sleep when temperatures are 27c at 4AM with humidity.

[@macmcleod1188]

@SonnyDarvishzadeh we are at the point that a large area of the globe is literally uninhabitable each year now. So in... you will die if power or a/c fails there. At some point, you or your kids will have to leave and move polewards. Yes.. it's unreasonable. But it's just reality.

[@Sum_SpaceX]

We have been using Geo heat pump powered by PV for 13 years now and enjoy both the cooling and heating @ 400% efficiency. The initial expense of installation was really quickly offset by the savings and during the summer has the added benefit of taking the humidity out of the air as well.

[@Lord.Kiltridge]

I have been thinking on exactly this. If the U.S. and Canada weren't chalk full of politicians in the pockets of oil and gas, legislation would have been passed decades ago requiring new home builds be designed to very different standards. I mean homes that are designed from the outset to be _inherently_ cooler without being entirely dependant on energy heavy AC systems.

[@misterbum1]

If wishes were horses.......don't complain, Vote Blue. Democratic party perfect? No. Democratic party the element of our government that passes legislation that helps Americans? Yes. You want change? Make it happen at the polling place and then make sure that those that you voted for listen to you. repulsigans, by their actions, prove that they support authoritarianism, big business, repression of women and civil rights, reductions in free education, health care and individual liberties. You, Lord.Kiltridge, can support our Democracy. Please do so.

[@dennisenright9347]

It's might be less a matter of politicians being owned by the fossil fuel industry than the fact that the overwhelming majority of the income from their use going into the coffers of government. Actually, eliminating fossil fuels would require public acceptance of a tremendous diminishing of government revenues and consequently the size and scope of government. The fact that politically the left supports the eliminating of fossil fuels and the right does not is ironic, because actually doing so would remake the world in the image of Reagan and Thatcher. Politicians don't really want the money they whose spending they control to be reduced.

[@mv80401]

I always thought that building codes in the US came out of a government department but in fact they're derived at by workshop conferences of stakeholders which include industry and the public.

[@sjsomething4936]

@@dennisenright9347there may be some truth to this but my understanding (I’m a layman and not in the industry myself) is that overall the government actually subsidizes O&G more than it gets in taxes.

[@sjsomething4936]

@@mv80401and the industry actually has the majority say in the policies and standards that get passed.

[@peterdollins3610]

Another great explaination of a very promising technology. Thank you for all your work on behalf of me and the public.

[@paulwary]

There's a lot that can be done to raise the efficiency of cooling, including using solar energy to create air flow, phase change energy storage with with sodium sulphate, and the Maisotsenko cycle which allows evaporative cooling down close to the dew point. But these types of systems are more complex, more difficult to maintain and more suited to large systems I think. Maybe the biggest gains you could make is to get people out of houses and into apartment towers, where you can use economies of scale. Good luck with that though!

[@tobiaszb]

That's cool! 😎❄️

[@dragonskunkstudio7582]

I only had 3 days of really hot weather this year, so my AC stayed in the closet this year. This year was beautiful in Montreal.

[@StreetcarHammock]

Good luck this winter, it gets frigid up there

[@dragonskunkstudio7582]

@@StreetcarHammock With any luck we'll have palm trees around town.

[@michealoflaherty1265]

Great video. The Transaera system looks to have a thermal wheel in it to alternately absorb and release moisture. Maybe combine either system with sky cooling and you could have a super low energy cooling system. You could also have one that doesnt work cos its too experimental. 😊😊

[@dennisschott2352]

Here's something that you can research. I don't remember which issue of Popular Mechanics (US) this article was found or even what year ( early 70's), but it was an article about General Motors developing a mechanical non freon air conditioner which they tested. The article went on to say that it was effective and actually increased fuel economy by 10%on the test cars. I remember from the pictures it was a tracked/belted vertical vane assembly that was attached to the front of the engine. It used the airfoil/ vane to expand the air volume to drop the temperature. GM dropped the concept from further development because they said that the airfoil/vanes couldn't stand up to the friction of the vanes contacting the housing. It was always my opinion that they stopped the project because of increased fuel economy. There was no discussion of additional materials testing to improve the friction problem.

[@lady_draguliana784]

A/C is needed for life, here in AZ... I'm ALWAYS interested in this topic!

[@dherrendoerfer]

Desiccant phase change emit just as much energy as hydrocarbon based phase change coolers - there is no cooling without emission. Even the ancient Greeks and Syrians knew that when they used amphores with caulk and salts to dehumidify their homes - use it, heat it in the sun, close it, cool it in the cold of night, take the lid off, and start over. The required energy was moving the containers and lids.

[@GuyIncognito764]

I live off-grid in 2 places. Part of the year on a boat. Part of the year in a small house. Both have PV and batteries. Both have a 5k BTU window AC unit that runs during the days (the house has 2 of em). No generator required. It's sunny when hot. This isn't cooling some 5,000 sqft house, but it's fine. Cheap even. People just need to downscale their expectations.

[@Sailorman6996]

Great ideas that needs to be spread. Save money, energy, the environment and the climate. Win win win

[@combinedstudy6427]

The full form of HVAC is Heating, Ventilation and Air Conditioning. The main difference between HVAC and AC is that HVAC generally refers to the whole heating, cooling, and ventilation system of a building, while AC often refers to cooling systems. In other words, AC is part of an HVAC system.

[@supermikeb]

Great!

[@carlbrenninkmeijer8925]

This is encouraging. What strikes me is that some small start-ups publish their technology. One would expect them to keep it secret... but whatever, it is great that nearly every think able solution is bring tried out.

[@bersheck3076]

The whole system again relies on a heatpump which is again a air conditioner in reverse would seem to defeat the purpose

[@petewright4640]

The Blue Frontier descant AC touts nighttime regeneration as an advantage. As grids go more to renewables, particularly solar which is plentiful and cheap where AC is mostly needed, then it makes more sense for power usage to be during the day, not at night when PV is useless. I've often thought that some of the worry about AC energy use is countered precisely because AC is most needed when the sun is shining and so is a good match for PV.

[@petewright4640]

Slightly disappointed that the solutions aren't a bit more radical than what is still essentially just making conventional AC more efficient. How about other approaches such as having ultra white roofs and heavy insulation combined with harvesting cool air at night and 'storing' the coolness for use in the day.

[@incognitotorpedo42]

@@petewright4640 Because that stuff is very expensive. Upgrading an AC is much easier/cheaper to do.

[@peterolorenshaw]

Something of a sidestep to cooling is cooling down structures by radiating heat to the cold night sky and insulating it during the day. We have concrete Trobe thermal walls on the sunny side of our house and I have toyed with the idea of having opening sort of French doors to open them up to the sky at night. Better really would be a solid masonry or water pond roof that you coudl slide away insulation during the night to let the coldness of space radiatively suck the heat away form the surface so by morning it is ready to start soaking up the heat right through the day, keeping the inside cool. So even in a place with a small diurnal heat range or permanantly overheated, you could have this natural space cooling as long as there wasn't too much cloud cover. Maybe you could have a massive enough structure to hold coolth for a few days of cloudy nights. And this massive structure doesn't have to be high embodied carbon concrete: I am writing this from our adobe (mud brick) earth house that although it has concrete foundations, the fairly massive walls have close to zero embodied carbon being all from the house site - with the only addition being some (carbon negative) chopped straw for crack stopping.

[@d.p.2680]

Desiccant cooling sounds great for off grid application in warmer climates, i want one

[@jmr]

Anyone interested in this topic needs to watch the Tech Ingredients video on "revolutionary cooling" where he builds his own air cooling system using desiccants. There us also a part two "solar powered air conditioning" where he acales it up. This channel should do a crossover or interview or something with them. I think we would get some really great insights.

[@barrycarter8276]

There is no such thing as almost “free cooling”, that’s almost equivalent to saying it’s almost perpetual motion, and as I’ve pointed out in my own comment, these savings in efficiency invariably result in more technology, technology that invariably owes its existence to Flammable Fossils, and efficiency that results in more energy not less being consumed, referring to Jevon’s Paradox: Fuel efficiency gains tend to increase, not decrease, fuel use. And we are looking towards sustainability and not a short term fix, aren’t we🤔

[@jmr]

@@barrycarter8276 You need to condition more with all those split hairs.

[@barrycarter8276]

@@jmr When you resort to attacking the messenger and not the message, you have lost the debate - Addison Whithecomb🤔

[@jmr]

@@barrycarter8276 I was absolutely referring to the message because the message sounds hopeless.

[@barrycarter8276]

@@jmr Well in one respect you are correct the message is hopeless, not my message though, the message that technology in this instance regarding AirCon, technology that leads us to hopelessness leading us further into the Red Queen Race, and ending with a lack of affordable FINITE Flammable Fossils (FFF’s), of sunlight buried over half a billion years but extracted 10 million times faster than sequestered… Daddy when your generation were supposed to be transitioning to rebuildables, sorry daddy renewables, you said it didn’t work because people wouldn’t give up on increasing their lifestyles, and so continued increasing consumption of FFF’s. You’ve told me not to waste energy, switch the lights off, only cook when we need to, rap up to keep warm, and justify why I need driving somewhere because energy is so expensive and hard to get, yet you and mummy daddy consumed energy like there was no tomorrow ignoring that it was FINITE, and so now my future looks bleak. Why daddy did you have me knowing what I’d be facing “The Great Simplification”. I’m really sorry pet it all seemed so good at the time, they told us Conventional and Small Modular Reactors using Fission, and Hi tech Fusion would be so cheap with little radio active toxic waste, but it never materialised except for that waste, I’m so, so, sorry Pet😞🤔

[@incognitotorpedo42]

4-7 hours of cooling per day would be inadequate in much of the world. I hope they're able to improve on that.

[@denisedraper9591]

Seems like you could put two reservoirs in series, so when the first one is nearing capacity, the second one comes into use. And recharge them in parallel.

[@marcofossa5741]

Grazie.

[@JustHaveaThink]

Thanks for your support. Much aprreciated

[@mattmyatt9078]

It would be really interesting to see if we could use a more closed loop system. One that could store the heat removed in the summer and exchange in the colder parts of the year. And the reverse. Great job! Interesting stuff!!!!

[@kaitlyn__L]

I was dubious of drying the air out only to get it damp again, until we got to the heat exchanger moving heat from the dry air into the fully contained colder damper air. Still a bit dubious as to whether the heat pump drying out the desiccant is much savings over the reversed heat pump of a regular air conditioner, but it’s undeniable they’re more efficient at night when the delta between air temp and condenser temp is higher. (This fact can also be used with regular air conditioners to save power if you run them overnight, assuming your home is insulated enough to still be cool when you wake up.)

[@hackmaster124]

I live in the deserts of the southwest US where we get enough sun to easily run A/C units purely with solar power. I'm really into the dual purpose of A/C's to cool and dry the air. Even though we don't have much humidity, the mini split I have captures around 1-2 gallons per day of condensate. I take this and put it through an RO machine to turn it into very good drinking water. This literally gives me all the drinking water I need for the whole summer. So I'm not contributing to plastic waste with bottles, and cooling off the house at the same time. With the unit fully powered by solar, the small amount of refrigerant seems worth it for what the device is giving me. So for me, I'd still want the ability to capture the moisture from the air. Here in the desert, that moisture is even more valuable than the cold air.

[@TheKhaosMagician]

The channel "Nighthawkinlight" has a couple very interesting building white cooling panels painted with nano-particles that passively radiates the sun's energy into space. Potentially all you'd need electricity for to turn it into proper cooling system would be a fan to move the around the underside, which could itself easily be powered by a small solar panel. I haven't done the math, but I would bet if you scaled it up that it would beat the efficiency of refrigeration systems in this video.

[@hyric8927]

Early in the video I see the A/C thermostat set to 18°C and it made me cringe. Hah. Here's a tip: keep a humidimeter in the room and try to keep the humidity in the 50-59% range. When the humidity goes below 50%, raise the thermostat by one degree. Be sure to also have a fan blowing the cool and dry air right at you. Using this strategy, I could keep comfortable up to a room temperature of 28°C as long as the humidity is in range or less. (It's been in the mid to high 30s outside).

[@thamiordragonheart8682]

I feel like one big common problem with most evaporative cooling systems is that they use up water, which is an increasingly scarce resource in many parts of the world, and most of these systems are going to use treated fresh water so they don't have to deal with scale buildup or biofouling in the plumbing. These systems get around the dry environment requirement pretty well, which is great, but they need to not use up precious fresh water. The two ideas I can think of are to make a version that is robust enough to run on seawater and use it near the coast or to design it to capture the water vapor and recondense it at night with dark sky cooling for reuse the next day.

[@guillermoherlt5141]

I would say the problem of the amouht of energy used worldwide is not just the efficiency of the heat pump in general, but also the bad insulation of the rooms/houses.

[@petewright4640]

An important point is that the assertion that conventional AC "waste" energy because they also condense water is misleading because comfort level is related to humidity. In many situations simply dehumidifying the air is all that's needed to make heat tolerable. The dehumidifying aspect of AC means that temp doesn't have to be reduced so much, thereby saving energy!

[@miroslawkaras7710]

Whenever I see that somebody talking about cooling I try to point the methode of air delivery to the room in AC system. The most efficient is displacement methods. The cold air is delivered to the floor instead of mix the whole volume of the air. That can save 40-60% of energy with added benefit of preventing of mix the contaminant and co2 expell from our longs as warmer air rize. No body put out that during Covid epidemic to use this type of system to ventilate occupying rooms.

[@chrisogilvie8133]

A hugely effective, cheap, easy, low energy help (but not a total solution) is to simply paint buildings white. This will reflect most of the heat, and the building will run a whole lot cooler. Test; next hot sunny day put your hand on various cars. The darker coloured ones will be so hot as to burn your hand, the white ones will be just warm to touch. Basic, Simple.

[@ecocodex4431]

5:04 SCOOBY DOOBY DOO!

[@christinavuyk2026]

There’s spooky, was just talking about greener air conditioners yesterday 😄

[@infocat13]

Like the folks at Kensa

[@cakeshoe]

As someone who lives in the hot and humid tropics, I can’t wait for a better and more efficient system

[@punkdigerati]

You can also use solar thermal energy to regenerate dessicant dehumidifiers, the liquid ones are technically easy to pump around but are typically corrosive. This could be part of a desuperheater for the vapor compression part, increasing it's efficiency. Desuperheaters in general should really be used anywhere there's heating and cooling needs, first to mind are restaurants that run both large compressors for refrigeration and have large hot water tanks for dishes.

[@mikedavison3400]

It’s on point that you mention restaurants. I’m in one ~30 years ago and I can hear water pouring down from within a structural roof support (nicely outfitted). I asked what that was as it was not raining. I was told it was the water from the rooftop AC being sent down the drain. Meanwhile natural gas and electricity are being used to create hot water for the dishwashers and the washrooms. I was left shaking my head.

[@falconerd343]

I remember seeing an article in Popular Science years and years ago about the NREL that developed a prototype of a liquid dessicant based, microfluidics device with a semi-permeable membrane to pull water out of the air. (found it! "NREL Improves On Swamp Cooler Tech" from Jun 2010)

[@miroslawkaras7710]

The are some add in for commercial heat pump AC: adiabatic eveporative pre cooling system. Pacifically useful in climat dry or mildly humid. I can save up to 35% on energy.

[@susanshepherd7093]

we use our solar generation to run our ac/heating split unit for most of the year. Very occasionally we use power from our batteries which are charged using off peak electricity.

[@BasilBear]

Thanks Dave, I found that information very interesting. I am utterly hopeless in very warm weather, and have recently given in to my own need for airconditioning at home to enable me to work - it hasn't been needed much this year, but on those few occasions it has been a game-changer for me, albeit with a sense of guilt. To know that there are some _cool_ innovations in the pipeline is most certainly very good news for us all, as I imagine that the need and the demand for air cooling are going to be rising for a very long time to come. Thanks for all your work, Victor

[@JustHaveaThink]

Thanks for your support Victor. Much appreciated :-)

[@Zer0Blizzard]

5:05 I like how it says "SCOOBY DOOBY DOO"

[@carlbrenninkmeijer8925]

it helps to dry the air in a room because we can cool our bodies much better when the air is drier. I have an energy frienfly solution. Inmagine a "window"with instead of glass a Nafion Membrane. This Nafion lets moisture through. The outside is flushed with air that is predried with a molecular sieve. This sieve gets hot, but the ambient air keeps that moderate. When the molecular sieve is saturated, it is heated with focused sun light and the collected moisture is driven off.

[@MrArtist7777]

I've used emissions free cooling, and heating, for years with my heat pump HVAC unit and solar panels and wind turbine.

[@GhostOnTheHalfShell]

I like to term one of the major challenges we face is de-energization. Removing energy use for common tasks. Climate control in buildings is one of them. Millenia old techniques are still known and should be utilized. There are movements in India (see Down to Earth) to revive and modernize de-energized housing. Packed earth construction with passive air conditioning surrounded by permaculture or the earth ships in the US. Consider that even lumber may come under constraint as forests burn (see Canada). We need a deep rethink of how we provide basic necessities like housing, food etc. Because integrated self sufficiency massively cuts our need for energy and a global supply chain.

[@mortimersnead5821]

I catch the condensate from my mini-split and pour it on my landscaping.