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New Air Conditioner Process Cuts Energy Use 50-90%
necro81 writes "The US National Renewable Energy Laboratory has announced that it has developed a new method for air conditioning that reduces energy use by 50-90%. The DEVap system (Desiccant-Enhanced eVaporative air conditioner) cools air using evaporative cooling, which is not new, but combines the process with a liquid dessicant for pulling the water vapor out of the cooled air stream. The liquid dessicant, a very strong aqueous solution of lithium chloride or sodium chloride, is separated from the air stream by a permeable hydrophobic membrane. Heat is later used to evaporate water vapor back out — heat that can come from a variety of sources such as solar or natural gas. The dessicants are, compared to typical refrigerants like HCFCs, relatively benign on the environment."
It's cheaper than using trained hydrophobes. Or are they used to create the membrane?
Nae king! Nae laird! Nae yurrupiean pressedent! We willna be fooled again!
So when will we be able to buy one of these? I know my wife is going to be asking for an AC in the house this summer, and I'm sure that the people in places like AZ, NM, and TX will be clamoring to lower their electric bill.
Additionally, will the dessicants (or the filter) have a recycle lifespan, or will it be more like a traditional household AC, using a 'simple' radiator device?
~/ssh slashdot.org ssh: connect to host slashdot.org port 22: too many beers
Heat is later used to evaporate water vapor back out — heat that can come from a variety of sources such as solar or natural gas.
or the servers that are being cooled?
Swamp coolers use a LOT of water. Is this better than them in terms of water use? If not, it's just trading one environmental ill for another. The places that have water to spare also have humidity high enough that even this system might not do so well with its evaporative cooling, and the places where evaporative cooling works best don't have the water to spare.
For starters, Americans should start insulating their houses better. That would cut the energy costs even more.
And otherr refridgerants like R-134a can also form deadly compounts when the degrade, but since they are in a closed system they can be used. I don't think the researchers anticipated tha eventuality that somone would open up one of thier units and drink the liquid inside.
quis custodiet ipsos custodes
Your suggestion is hardly a solution for the vast majority of people who cannot renovate their home to meet standards. Apartment superintendents, landlords, and hell even members of your community can throw a wrench in your plans. Even if theres no opposition, renovation still requires licenses, permits and other red tape. $DEITY forbid you live in a "historic" area. Air conditioning is a technological advancement just as any other. Take advantage of it and move along.
It does say these dessicants are relatively benign compared to the presently used refrigerants.
But you are spot on with the rest of your post, proper insulation and appropriate construction techniques would go a long way in limiting the energy consumption of buildings.
In the mean time we here in N/W Europe we can only hope for weather warm enough to switch off the heating.
"The likes of Facebook and WhatsApp are free to those whose privacy is of zero value."
Sheesh, RTFA, already. They mention the coolerado and explain exactly why this new idea has the potential to do better.
Or, maybe,
As TFA states, desiccant cooling has been known since at least Carrier's work at the turn of the 20th Century. The trick has always been to make a practical desiccant cooling system.
but it doesn't matter, its still years away from practical
NREL has patented the DEVap concept, and Kozubal expects that over the next couple of years he will be working on making the device smaller and simpler and perfecting the heat transfer to make DEVap more cost effective.
I lost interest at this point. Wake me up when biochemists and medical doctors get a chance to run test case groups about the adverse effects of lithium in their localized atmosphere, typically inhaled into the lungs and later causing one's sense of reality to become skewed.
Well what about the Sodium Chloride option. People have lived near oceans without adverse effects.
Few people have heard of the true inventor of both air conditioning and the artificial ice machine, Dr. John Gorrie, of Apalachicola, Florida, who received the first patent (number 8080) for a machine to make ice, on May 6, 1851. While it was reduced to practice (he used it to cool the rooms of his fever patients, and gave iced drinks to his guests at parties -- a fantastic novelty in 1850s Florida) he was unable to make a financial success of the venture. His machine was the first to make use of the refrigeration method of air conditioning.
I lost interest at this point. Wake me up when biochemists and medical doctors get a chance to run test case groups about the adverse effects of lithium in their localized atmosphere, typically inhaled into the lungs and later causing one's sense of reality to become skewed.
In order to get lithium chloride vapor in the atmosphere, one would have to raise the temperature to about 1600 Kelvin at normal atmospheric pressure. Under those conditions, I propose blind panic as a suitable coping strategy.
I don't think the researchers anticipated tha eventuality that somone would open up one of thier units and drink the liquid inside.
So if they don't do stuff like that, then whats the point of having grad students?
Monstar L
If you're building new, modern building codes result in a more insulated space. In my opinion modern codes -- even those in CA or the "stretch in MA or the base points in LEED -- aren't aggressive enough, but they're far better than existing conditions in most buildings. Of course, the same opportunities exist for major remodeling or work on the exterior.
Sometimes, though, the mechanical unit needs to be replaced, and quickly. In those cases, would you prefer that this new AC not exist (assuming they work out any chemical safety issues)? For spaces which are currently being used, the interruptions caused by upgrading the building envelope may be intolerable, a non-starter. In those cases, would you rather this new AC not exist?
You're absolutely right -- improving the insulation and air-sealing of our building stock would have a remarkable impact on our energy use. Still, this new AC system, if it works as advertised, can be applied to buildings for which an insulation and air-sealing upgrade simply isn't in the cards in the near term.
Adding another tool to the belt isn't a bad thing, as long as we continue to use the right tool for the job. Building codes will help ensure that we do.
Support a few technologists in Washington.
This is not really a closed system though - the hydrophobic membrane can not be 100% efficient. OTOH, you can get a salt water inhalation solutions at a pharmacy, to help with drying up eyes and nose - some salty water in the air may be a positive thing. (still, not the optimal solution for server rooms etc).
45 5F E1 04 22 CA 29 C4 93 3F 95 05 2B 79 2A B2
Botijo: http://en.wikipedia.org/wiki/Botijo
Heat from air evaporates water to cool air; heat from natural gas evaporates water from desiccant. Where does all this heat come out?
That's all well and good, but I'd rather see efficiency advances in solid state cooling (quieter, more reliable, often smaller...)
Why OpalCalc is the best Windows calc
I keep my house at 78 in the summer, I have ceiling fans in all the rooms I frequently use in the day. Throw in nine foot ceilings and it is very comfortable; especially when compared to the 90+ high humidity days we have in Georgia. Last year my highest bill in the summer was $140. This is four thousand square feet of home. Granted the other electrical costs are pretty low because of CFLs everywhere, a LED based projection tv - we only have one tv, and Macs/Pcs that sleep often.
That compares to some friends of mine who burn through $300 or more per month in the summer to keep the same or smaller homes; sometimes half the size; at ridiculously low temperatures, like 72. Throw in lights on everywhere it seems if not a TV or two both running and it becomes easy to see that insulation alone won't help. Most laws in recent years require much higher R value for homes but behavioral changes must also take place. People need to want to conserve. Children especially need to learn conservation in schools in ways that does not lead to being combative at home.
Encourage good behavior by allowing people to opt into reduced rates for sensible living. This means power meters than not only record usage but can record how its used, as in knowing what temperatures you set and such. Some regions already offer reduced power costs if you elect to lose power during certain periods to reduce the load on the whole system but it doesn't help when the behavior of those who use power inefficiently.
* Winners compare their achievements to their goals, losers compare theirs to that of others.
Cause Coolerado uses Flash and TFA HTML5?
It must be hard to spell the word "desiccant" correctly, especially after you have just copied the correct name (Desiccant-Enhanced eVaporative air conditioner) from TFA.
Escher was the first MC and Giger invented the HR department.
We are getting a new AC system in our DC in a few weeks and this sounds pretty much exactly like the things they do.
Can someone enlighten me, please?
Is that we'll all have this in 3-5 years!
Adsorption coolers (http://en.wikipedia.org/wiki/Absorption_refrigerator) are far better as they use water as a coolant and heat energy from solar panels. In fact, they consume only electrical energy for the controlling electronics...
Well what about the Sodium Chloride option. People have lived near oceans without adverse effects.
Well, to give you the required car analogy, salty air makes cars rust faster.
I eated a pack of silica gel.
Confucius say, "Find worm in apple - bad. Find half a worm - worse."
A desert is an ocean with its life undergound, and a perfect disguise above.
Or is it the other way round?
Confucius say, "Find worm in apple - bad. Find half a worm - worse."
My home stays 70 degrees at 50-55% RH year round. My power bill runs about 150-175 a month. My gas bills runs about 65-75 a month from late Oct to late Feb. Here in the next year or two, I will go ahead and have either a couple of cooling wells drilled or DIY a trench system for a geothermal HP. I am still using a 10 SEER HP and 90% propane converted furnace. But then again, I spent good money and a lot of effort installing insulation when building, and making an optimal duct system, along with using ERVs. I spent close to 9 grand 4 years ago when building, on HVAC/insulation. The average home owner would pay around 15 to 20K for the same set up. Owning an HVAC/R company does pay off at times.
You're making it out to be much more expensive than it actually is. If you really have 1930's construction, then insulating your home would be relatively easy and cheap. Between each pair of studs in your wall (and, possibly, ceiling if you have no attic) a hole is drilled and the gap is filled with a ground newspapers and phone books. Then you repair the holes. It has quite good insulating properties and is relatively cheap. The 1930's status of your construction actually helps, since you won't have firebreaks to drill under. (Newer construction has a row of vertical studs, called a firebreak, halfway up the wall the prevent fires from spreading as quickly.)
People will just run it longer, or leave their windows and doors open all the time, to make up for the energy savings
You're right. There's no point in doing anything, ever. We should all just die. Also, you hate your parents, right? Because they wouldn't get you the bigger iPod?
Don't disappoint your bird dog. Go to the range.
Chemist who works with LiCl reporting in (Specifically LiCl enhanced potentiometric buffers).
I won't be using it in my house for a simple reason: If that "membrane" gets punctured you're going to have one hell of a cleanup cost. I won't even go into the aerosolized effects. Check out any SDS.
That's boiling, yes. But LiCl in water can easily aerosolize. Think Nebulizer treatments on a household scale.
You need to do more research. You can put R-400 in the walls and it won't help, because you are dealing with a building that has windows and occupants.
In most places, solar heat gain is a major component that A/C has to deal with. Humidity in the makeup air is also a large problem for A/C to handle.
Humans inject heat and water vapor into the building through cooking, respiration, appliances, and opening doors.
Humans also need fresh air, and you can't -- legally or practically -- build an air-tight building without makeup air.... which introduces more humidity and heat into the building envelope.
I built my house 2 years ago and used all closed-cell spray foam (isocyanate) making all walls, floor, and roof, water-tight and air-tight. 133 mm of foam gives me R-37 in the walls, and more gives me R-60 in the floor and ceiling. All ducting is in conditioned space. All external walls have thermal breaks (offset studs). I have an ultra-efficient water-jacketed earth-coupled geothermal heat pump. The solar gain in the summer still rapes my house with heat gain. The makeup air I have to have because the house is so damn air-tight, uses a high capacity heat exchanger, but still is a water-vapor sieve pumping water vapor into the conditioned space that the A/C has to then remove.
So do a little more research before you spout off with drivel.
Do you perhaps mean a row of horizontal studs?
The preferred solution is to not have a problem.
I don't think people run air conditioning just to burn a set amount of energy. They run it to feel comfortable and if an advancement helps them reach that point more efficiently, all the better. There will be some edge cases (people who might otherwise not have turned on the air conditioning because they were only a little warm and it costs a lot to run), but overall if savings really are anywhere near 50-90% this should more than compensate for those cases. As other people have pointed out, there are bigger issues here than people just running the AC a little longer.
Has the potential to do better in hot and humid climates (and might do better in hot and dry climates, although it might be more expensive)
Who pissed in your cornflakes this morning?
An important change for education.
As a fellow mechanical engineer, I would have preferred you considered more practical matters, along with cost-benefit and time value of money considerations before you shot your mouth off. Either that, or not mention you're a Mechanical Engineer.
Other responders have covered these things adequately, so I won't repeat them.
Alcohol, Tobacco and Firearms should be the name of a store, not a government agency.
If there is a possibility of creating a passive system over and active system, I would go with the passive system.
Part of the problem is that buildings aren't always designed with their geography or climate in mind. One solution I have seen for passive cooling of a building is a Wind Catcher ( http://en.wikipedia.org/wiki/Windcatcher ). Also, depending on geography you could add natural plants to help provide shade. None of this sounds as sexy as a high-tech AC unit, but it is probably much more cost effective and lower maintenance.
I am not sure what solutions there are for existing buildings, but I would be interested in hearing about some.
Jumpstart the tartan drive.
Your argument is bogus. R30 fiberglass bats are 9 1/2 inches thick. Are you saying to frame the walls with 2x10s. You know the cost of dimensional lumber increases geometrically with dimension, right. Or do you stagger frame with 2x6s...basically build each wall twice and double your labor costs?
What about existing structures? Because the US market has enough backlog of existing structures. Do you build another layer of insulation INSIDE the house and lose a foot of floorspace near each exterior wall..and then pay to reframe, drywall, move out electrical outlets, etc? Or do you reframe the exterior of the house and then cover and weatherize your new outside envelope?
In either case, what about windows and doors? You do know that heat will gladly take a parallel path. Third-year ME heat transfer class...remember the resistor analogy? You can make the walls R300 and the heat will still get in (out) through "holes in the bucket." Have you priced super high R glazing options? Do you want a 8" thick front door? Even in the walls themselves, you have to worry about thermal bridging through the wood studs...all these would be problems even with some crazy aerogel insulation that is R50/inch.
The building standard is what it is for a reason. It is an engineering trade-off between cost and performance. R30 in the ceiling and either 2x6 walls with R18 or 2x4 walls with R11-12...and maybe a dense insulation board on the outside before siding is installed. Double pane insulated glass windows. Now those trade-offs were in considered with energy and HVAC hardware costs at a certainly level. And more insulation is good but only to the point. The insulation costs goes well beyond the price of the insulation bat, and a point exists where adding more makes no financial sense. If you *insist* on having windows and doors, it doesn't make engineering sense anymore either. Your recommendation is well past that and smacks of niavete. Build or remodel a house or two (especially using your OWN MONEY) and then get back to me. A home built to your bogus specifications would cost four or five times more. I doubt you could find someone to build it for you.
If you want to look into green houses, then look into earth bearmed homes, rammed earth homes...building underground, using lots and lots of earth as thermal insulation and thermal mass. Folks have been doing this since the 70s and there are books that give some good overviews. I'd like to see the building codes revised to make it easier to build some of these different "hippie" houses.
And in sunny climates, I think the best ROI would be a 100x100 white canvas tarp and support structure to shade your entire house. I'm surprised no one does that. That would effectively remove the direct radiation load from the cooling...which is significant...just ask your barefeet after a walk across sunlit asphalt.
I'd rather have an air-con that works at 50% efficiency 95% of the time than one that works at 95% efficiency 50% of the time.
Given how long we've had to get regular aircons working, and how badly we seem to FAIL it, I think it'd be a great idea for everyone else to try out this wonderful new technology. Maybe get back to me in 20 years or so to tell me how it worked out for you.
If you were blocking sigs, you wouldn't have to read this.
To pose a question, why not just stick R60 everywhere? although your windows are not going to be R60 even if they are new. You are also probably far better off installing a ground source heat pump and putting 95% eff. reheat on it(for really cold days) than you are to tack the AC on as an afterthought. Then again, Air is a pretty bad heat transfer medium anyways, maybe in floor radiant heat would be a better idea. Salt water, or mineral oil would be good choices fro the fluid as they have a large thermal mass.
There are also a large number of homes that were built over 100 years go, and are in historical districts that have codes on the type of construction allowed. so how do you propose to upgrade those houses in place to >R30
All of the above was encrypted with a Quad ROT-13 method. Unauthorized decryption is in violation of the DMCA.
He might be justifiably terrified of blowing ground-up paper at high speed onto degrading fabric-insulated, ungrounded 120v wiring, no matter how much boric acid is mixed in. Shorted neutrals are fucking scary. Not sure what he means about the plumbing, though, unless he's waiting for his homeowner's insurance to replace his immenently failing pipes.
All these stories about things to come out, how about a story once where you hear your local hardware store now HAS this new air conditioner ready for you to buy, and save 50, to 90 percent energy....then I will be interested...seriously , this has got to stop!
Breaking news> A scientist came up with a new idea last week to help with global warming,
has it written down on paper...more news at eleven....
The answer just like with power station cooling towers or large aircon installations is DON'T GET THE STUFF IN YOUR LUNGS because there is very likely to be other nasty stuff there as well. Modern society uses a vast array of poisonous materials and instead of waiting for "biochemists and medical doctors" to declare everything safe the adult thing to do is put some form of barrier in place to keep the nasty stuff out of people's bodies.
Fact: The most efficient air conditioning system is hiring one of the millions of out of work Americans to walk around and fan you 24 hours a day. Even the Amish would buy into it.
hello world
What I noticed was the lack of any mention of the cost of desiccant, or how to reuse it. A sealed AC unit may have 13 pounds of hydrocarbons, but, unless something goes horribly wrong, all these chemicals are tightly contained. An AC system can also reuse these CFCs indefinitely, while the desiccants have a finite water absorption amount.
How does it compare with efficiency of propane cooling? For the foreseeable future propane will continue to be created by oil industry, regardless of the idealism of some environmentalists, so it will continue to be used in homes for heating. For cost-saving purposes, propane fridges and freezers are being used quite often in remote areas - they are also extremely efficient. I am curious how the two systems compare in efficiency.
As for the canvas tarp, have you run any wind load calculations on such a structure? That's why. Large trees on the south/west side of the house achieve much the same effect. Radiant barriers inside the attic in conjunction with good venting also have their advocates.
Remember, separate your grad student: Females under the desk, males on the dissection table.
MMO Quests are like orgasms:
You may solo them, I prefer them in a group.
But in areas where you need Air Conditioning (i.e. cooling + humidity reduction) in a humid climate it is useless (i.e. Gulf Coast, deep south, Florida). And this area is where the bulk of energy use is used for (indoor) climate control.
So why don't researchers work on a solution for the 80% that could use it instead of the 20% where it doesn't matter ?
Maybe we need to move their labs out of AZ, CO, and CA down to TX and FL and only allow them to use their own inventions to cool the lab.
A better way is self expanding foam, it will even insulate homes that have the crappy 1st gen fiberglass batting. it just requires COMPETENT installers so they dont put in too much and burst the walls.
I did an entire 2100 sq ft home for less than $2200.00 that included adding an extra 18 inches of fiberglass batting to the attic. My heating bills dropped from $210 to $80 a month in the winter with a 25 year old 55% efficient furnace. this summer that get's replaced with a 90% efficient furnace.
Do not look at laser with remaining good eye.
For me the basic rule for chemicals is, that if I don’t know if it’s good or bad, then it’s bad until proven good.
And lithium chloride definitely is more in the bad area than in the good one.
I’m not going to get in a room with that stuff, until all effects and all cross-reactions are studied and proven to be OK by trustworthy sources.
Any sufficiently advanced intelligence is indistinguishable from stupidity.
It only costs $2000.00 to add a air makeup unit that is an air/air heat exhanger on it. that is almost nothing in the cost of a new home ,yet MOST homes are not built with one because homeowners are not educated enough to make sane decisions on their home design.
Do not look at laser with remaining good eye.
Your straw man arguments fail to make us fall for it.
We did not talk about lithium chloride vapor to get into the atmosphere, but only lithium. We did also not talk about it having to be vapor. “Dust” suffices.
Any sufficiently advanced intelligence is indistinguishable from stupidity.
What about the solvent? I hear they're using dihydrogen monoxide! http://www.dhmo.org/facts.html
Confucius say, "Find worm in apple - bad. Find half a worm - worse."
"Honey, we are out of Gatorade, and by the way, did you get my prescription filled?"
"No, just tap into the air conditioner line, it's okay if we are hot for a day or two."
Knowledge is how to play a game, intelligence is how to win, wisdom is knowing what game to play.
I lost interest at this point. Wake me up when biochemists and medical doctors get a chance to run test case groups about the adverse effects of lithium in their localized atmosphere, typically inhaled into the lungs and later causing one's sense of reality to become skewed.
Isn't this where the reavers came from? Lithium chloride in the atmosphere to calm the population, caused 99% of the people to give up and die, and sent 0.1% into a psychotic rage?
Oh, right. That was a science fiction movie. I always get those confused with reality.
John
Instructable, my York is on it's last legs!!
Si vis pacem, para bellum! For evil to succeed good men need only do nothing!
This is a perfect example of how any approach to reducing the carbon should be handled.
Instead of brow beating everyone into paying more for less and prattling on about the environment and how we are all going to die, just make a device that accomplishes what you want while making it cheaper for the consumer.
Reduce Carbon, impact "global warming"...sorry, "climate change", pay more = boring, politically charged, scam written all over it.
Reduce cooling costs 50%-90% = Where can I buy one NOW!?!
This is what you call a win-win.
When Fascism comes to America, it will call itself Anti-Fascism, and tell you to give up your guns.
ok, here's easy technology to get your domestic AC to consume about 50% less. All you need to do is continuously spray your radiator with water. This can be recycled via a tub sitting under your AC.
All the benefits of both technologies and you chill all the way to the bank :)
Dont make a better sig, you insensitive clod!
I don't believe NaCl is nearly as effective as a desiccant as CaCl or LiCl is, especially once in an aqueous liquid solution. (NaCl still has some desiccant properties but not much at this point, while I believe CaCl is still a strong desiccant at this point.)
retrorocket.o not found, launch anyway?
That's just silly. One property of salts it that they don't go airborne easily; it's thermodynamically unfavorable. Do coastside houses look like submarines? I think not.
not for sale yet. It is . . . vaporware.
Do you perhaps mean a row of horizontal studs?
Do you perhaps mean joists?
Or, wait until the siding needs to be replaced and put a shell of insulation around the outside of the house, and a wrap (i.e. Tyvek) if still necessary. Obviously this won't work if you have brick, or anything other than siding. You can insulate the walls from the inside, but there will probably still be gaps and holes everywhere. You can leave your scary 1930's wiring and plumbing in place. It would probably make sense to wait until the roof needs major repair to upgrade it, since you'll already be paying to have it removed. Or just throw some insulation up wherever you can easily for a partial solution.
Lithium chloride is already commonly used in absoprtion refrigeration and in dessicant systems. It has not proved a health problem.
One problem it does have: If the heat balance gets slightly off, the equipment "rocks up", that is, you end up with pipes full of solid lithium chloride. If this system were to be deployed widely to residential and other non-technical customers I could see it happening fairly often. Have fun with that.
TFA didn't really describe the refrigeration cycle being used, but it sounds like the only innovation is the hydrophobic membrane used in the heat exchanger. My guess is that the dessicant removes moisture, which raises the temperature of the air but lowers the wet bulb, and a direct and/or indirect evaporative cooler then reduces the tempeature to reasonable levels. This is nothing new, but is somewhat unusual because it's much easier to buy an off-the-shelf refrigeration system that is cheaper to buy and install and needs comparitively little maintenance.
TFA was isleading in some ways.
For one, they muddle the difference between evaporative cooling and dessicant drying. Evaporative cooling adds moisture to the air, exchanging sensible heat for latent heat, reducing the temperature but not significantly changing the overall heat content of the air. Dessicant dehumidification absorbs water out of the airstream which relases heat, raising the temperature of the air in exchange for reducing the latent heat of the air. These are two totally different processes, they can't both happen "all in one step".
For another, the dessicant cycle requires heat and the evaporative cycle requires water. Neither of those is free, and, pretty charts not withstanding, TFA offers no explanation of how this system saves money, energy, or.the environment. (not saying it doesn't, just that the same natural thrmodynamic limits apply to both mechanical cycles and this cycle, and TFA dioesn't explain how this works better than a good mechanical refrigeration cycle)
Also, any new A/C system is not going to have CFCs or HCFCs, those aren't allowed in new systems any more. (the new refrigerants still have some global warming potentials, though)
Yes, I am doing wind load study. It is all about the shape. Check out the tensile roof at the Denver airport...and that is designed for wind load and snow load. It is certainly possible to build such a thing.
My pet design projects is an earth-bermed house with a very large "courtyard" that is covered with a tensile roof, likely two layers with a sandwich of R30 between and southfacing opening covered with greenhouse glazing. So, in the summer, the white canvas will reduce the radiative load, the R30 and the thermal mass of the ground will moderate the temperature year round...maybe 40-50s in winter...70-80s in the summer. Then only space condition the earth-bermed rooms around the periphery. I can design it and make sure it works...I can add a few "earth tubes" if I need additional temperature moderation. And with steel wire and proper shaping, I can make sure it holds up. The big task will be getting a building inspector to sign off on it. Of course, I've already convinced my wife that should could garden year-round (in PA) if I built it. So maybe the hard work *is* done.
You need to chill out. Maybe you should take some lithium.
Gamingmuseum.com: Give your 3D accelerator a rest.
I live in a beach house. My toaster rusts. Everything I have rusts.
I deal with this by buying less expensive stuff and budgeting for replacements.
This would not be acceptable for my office.
I used to have a cool sig, back when I cared
Do you perhaps mean a row of horizontal studs?
Do you perhaps mean joists?
Neither. The horizontal pieces between the studs are called firebreaks. They are there solely to slow fire down and help prevent it from spreading between building floors vertically through the wall stud space. They don't serve much mechanical structural purpose, but they do also help prevent vertical cold air flow inside the walls which helps the insulation (fiberglass insulation doesn't stop airflow, it just filters out the dust).
The 1920s portion of my house does not have any firebreaks in two of the exterior walls, as it's built using so-called "balloon framing" which used long vertical studs that run continuously from the rim beam on top of the foundation all the way to the attic. Because of this, cold air can flow down the walls from the attic in winter. I've injected firestop foam into strategic parts of the wall to stop this, as I found some parts of the interior wall surface were below freezing last winter.
Putting moderation advice in your
"NREL has patented the DEVap concept ... Eventually, NREL will license the technology to industry"
I thought that inventions that we all paid for with our taxes were public domain. How is it that this government lab will be licensing this technology?
Clearly, before starting any insulation project you have to upgrade any knob-and-tube wiring. Even if it's in good condition, it requires air flow to stay cool.
Gamingmuseum.com: Give your 3D accelerator a rest.
This is another typical over statement. They calculated the efficiency without including the energy that is required to reverse the desiccant used thus the calculation is misleading at best and really just a lie. This seems to be a trend that started with "zero emissions" cars that had the electricity magically appear.
Believe it when you see calculations based on a closed loop system as I am betting that the efficiency advantage will tumble a LONG way.
That's hardly "throw a tarp over a typical single-family home" from your original post. Of course it's possible to build tensile structures, but the cost for a retrofit like you originally described is completely prohibitive from an ROI standpoint.
I hear you, but the thing is, you don't really want to encourage people who don't know what they're doing to be dinking with their electrical and plumbing (especially both at the same time!) Not only is there the risk of a house fire/flood their insurance won't cover, but running afoul of the building inspector (in jurisdictions where homeowners aren't supposed to touch the machanicals), or needing to call a pro to fix a botched DIY job is expensive.
Also, while any schmo can patch 2" holes with a joint knife and a bucket of compound, rehanging and taping full sheets of drywall requires a lot more competence, upper body strength, and access to a pickup truck or larger.
Based on your recommendations, I am going to abandon my precision engineered abode and live in a cave.
Be reasonable. Drywall may be messy, but it's not exactly an engineered science. Anybody who isn't an invalid can do it.
You're salary will be $5000 - $200,000 per year. Would you like the job?
FTA:
"NREL has patented the DEVap concept, and Kozubal expects that over the next couple of years he will be working on making the device smaller and simpler and perfecting the heat transfer to make DEVap more cost effective.
Eventually, NREL will license the technology to industry, "We're never going to be in the air conditioner manufacturing business", said Ron Judkoff, Principle Program Manager for Building Energy Research at NREL. "But we'd like to work with manufacturers to bring DEVap to market and create a more efficient and environmentally benign air conditioning product." "
Anyone else bothered that a publicly funded organization now owns a patent to this 'new' technology?
From the article: "highly concentrated aqueous salt solutions of lithium chloride or calcium chloride"
From the summary: "very strong aqueous solution of lithium chloride or sodium chloride"
Dumbed down too much.
Sometimes they fool you by walking upright.
As anyone who lives in a coastal area knows, the salty sea air will rust steel severely. Cars, cooking gear, electronics are all vulnerable and short-lived in such areas. So it is a necessity that they do a good job of preventing any salts from becoming airborne.
R30 fiberglass bats are 9 1/2 inches thick
True, but fiberglass is far from the best insulator we have. Today I'd argue spray foam is the better choice in most cases. Natural vapor barrier and no air leaks.
Aerogel insulation would be neat, but isn't yet commercially practical. Then again... R-50 per inch (10x foam).
Fiberglass, loose-fill: R2.5-3.7/inch, Batts: R3.1-4.3
Foams: R3.6-7
When I get around to building my own house, it's going to be a low energy cost one, but even I'll admit that I'll be sacrificing a few rooms worth of floorspace to get it...
I don't read AC A human right
I disagree. Nothing said it has to be permanent. The "tarp" solution could be nothing more than a large scale version of the Sunsetter. Just reel it in when the weather sets in. The ROI for that could be quite good, especially if roof and wall insulation is not easy to improve.
Even if the runoff water from this AC unit isn't filled with toxins, then AC units have life spans, which means pretty much every unit they ship is going to end up in a land fill or dump somewhere. So, sure, this is about making cold air and saving energy, (if the press release is truthful), but it's ALSO a clever scheme for invisibly distributing a rarefied psychoactive substance used in anti-depressant medications into ground water.
And everybody sure loves air conditioning! We're talking millions of gallons of this stuff over a few years.
Combined with the billion or so cell phone and laptop batteries which are currently and ever-so-quietly leaching lithium into the environment, I do pause to wonder why the government is so eager to exacerbate this situation.
-FL
C'mon guys, this isn't rocket science. Keep it modular and keep it off-the-shelf, right?
First stage, convert a regular evaporative cooler to pump the dessicant solution instead of water. It just needs to be highly corrosive-resistant. Now your incoming 100F air at 40% RH is now like 120F at 10% humidity or something like that. Hotter, but drier.
Next, you need a heat exchanger to pull some of that energy out without adding humidity. Adobe Air makes a modular product to do this. Or, you can skip this piece and get a two-stage evap such as the OASys. Or just insert a Coolerado here.
Finally, to really get cool temperatures, we need to add water back in. If you inserted a two-stage unit above, you're done. Otherwise just use a regular-ole evaporative cooler here.
Since we actually want to make this feasible without vast quantities of free energy, we will recharge the dessicant in a more sustainable manner. Obtain two empty swimming pools. The first pool is for the dry dessicant, the 2nd pool for the wet dessicant. After the cooling season, use a small solar concentrating array to recharge the dessicant pool. It'll take all winter but that's fine.
The makeup air I have to have because the house is so damn air-tight, uses a high capacity heat exchanger, but still is a water-vapor sieve pumping water vapor into the conditioned space
There now exist air-air heat exchangers that also balance humidity -- they are expensive, though from my research, they work quite well. A light-colored roof (and walls) can help a lot too.
Putting a radiant barrier in your attic (even if you need to add venting too) way cheaper, more neighbor/inspector friendly, and better for you home's value with close enough performance to the overengineered eyesore you're proposing.
Note that this doesn't mean I have anything but respect/admiration for the berm/tent design you're building; it just seems a little nuts as a retrofit for a typical suburban USian house.
I built my house 2 years ago and used all closed-cell spray foam (isocyanate) making all walls, floor, and roof, water-tight and air-tight. 133 mm of foam gives me R-37 in the walls, and more gives me R-60 in the floor and ceiling. All ducting is in conditioned space. All external walls have thermal breaks (offset studs). I have an ultra-efficient water-jacketed earth-coupled geothermal heat pump. The solar gain in the summer still rapes my house with heat gain.
Plant some shade trees? I realize that decent size trees aren't that cheap, but if solar gain is your major problem, then perhaps it may have even saved money.
I don't understand - what is the name of your horse?
It is not the doing of things that is difficult. What is difficult is getting in the right mood to do them. ~~ Brancusi
The idea of using a salt-based desiccant and heating it to release the water has been around for a long time. The liquid aspect of that desiccant, and the permeable membrane seem to be the new ideas, here.
As long as it pumps out cold air, and lowers the cost a bit. I live in New Orleans, and my AC pretty much runs on full from end of March through about the first of November. You have to....
I've already resigned myself to sign over half my paycheck this time of year to Entergy. Any help on that greatly appreciated.
Man, I look at those old pictures of people in the days before AC living in NOLA and wonder how the hell they did anything down here? I mean, first, they are all dressed from head to toe on hot summer days, most work was still outdoors...how did they do it without dying of heatstroke and smelling horrible all the time?
Light travels faster than sound. This is why some people appear bright until you hear them speak.........
I'm not sure I've actually heard of any large-scale commercial recycling efforts (other than, I think, Toyota recycles the batteries for their hybrids), but shouldn't lithium (from batteries, electronics, and evaporative air coolers) be recylable? It's not like the lithium is destroyed by use - it simply ends up in different compounds, right?
Why not just recycle it?
First, we find a new technology that will make a HUGE impact.
Second, we find ways to introduce it piecemeal over a 5 year period... such as find ways to make said new technology less efficient... Once we figure that out,
Then and only then can we begin production working our way up to 50% over the 5 year term.
After that, we look for a new technology to compete and confuse the consumer while we ramp up to 90% efficiency.
So, you see you're not getting a new Air conditioner that will use 50%-90% less energy in the next year or so... You MIGHT get one that one next year that uses 10-15% less energy if your lucky...
It'll also cost you 20%-30% more.
Wasn't there a Mel Gibson movie? One where he's an eclectic inventor who comes up with a refrigerator and moves to Central America with his family? I don't remember the entire plot but I think something happens and then the refrigerator winds up polluting the river.
Yeah, I know, not a memorable Mel Gibson flick... but it did follow an Apocalyptic ending, which is the genre for most of his films.
Harrison's Postulate - "For every action there is an equal and opposite criticism"
Calcium chloride is interesting: put a pan of it in a humid room and it dissolves in the water it absorbs. But it also gets hot when it does so, which would seem to defeat the purpose. I wonder how they get around that problem.
> The dessicants are, compared to typical refrigerants like HCFCs, relatively
> benign on the environment
Correction. The dessicants are relatively benign on the super-high level atmosphere compared to HCFCs, which are nigh infinitely safe to biology.
How do the dessicants fare when they leak out into someone's house?
(-1: Post disagrees with my already-settled worldview) is not a valid mod option.
I have a house with a similar system (just purchased).
My first house had an 80's correctly sized boiler with natural gas. It was a 1200 sq ft row home.
It cost me more to heat than my new home (both built 1928), with foam blown in and real attic insulation. The new home had a fifties, very oversized, oil boiler. The new home is 1400 sq ft, and both had similar windows (old windows with storm added). At the time gas vs oil was similar per/BTU.
Wow, sent an e-mail as suggested when clicking on "use classic" banner, and got a fast response that addressed my msg
They're using a dessicant to pull water out of the air thereby reducing the humidity. It sounds more like an adsorbtion chiller but using liquid rather than solid dessicants. They've been around for donkeys years but are expensive.
Deleted
Epic typo.
It cost me more to heat the old home, with far less exterior wall (row home), than the new one.
Jeez I can be stupid.
Wow, sent an e-mail as suggested when clicking on "use classic" banner, and got a fast response that addressed my msg
Seriously, geo-thermal HVAC is the RIGHT way to go.
I prefer the "u" in honour as it seems to be missing these days.
No, I do not.
The GP said "a row of vertical studs" when referring to firebreaks, which are short pieces of stud-material that run parallel to the floor, halfway up, inside the wall. The intent is to stop/slow fire from spreading quickly up inside the wall.
Those are clearly not vertical. They are horizontal. Hence my post.
Joists are horizontal boards that support floors (and perhaps roofs, I'm not sure about that.)
The preferred solution is to not have a problem.
Ah, you're right. I admit, I read your post quickly, and assumed (incorrectly) that you were trying to communicate that he ought to put insulation between the joists (as well as between the studs), and were using the term "horizontal studs". My mistake, sorry about that.
Fucking AC faggot. Since when does a refrigerant come into contact with a heating element in an HVAC system? Protip jackass and the faggot who modded my post flamebait, is that it doesn't. Talk about something you know and not some BS pulled from a wiki that is not relevant to the discussion. When you get your NC H-1,2 and 3's and are a fully licensed contractor capable of doing any HVAC/R in the state from ice machines to 200 ton plus chillers, then come and talk about HVAC/R. Until then shut the fuck up. I refrain from making many comments about tech stuff, since I am not a tech geek. I read, and ask questions, figuring that let the folks who know what they are talking about do the opinionating. I do know HVAC/R faggot, so as I said. STFU.
My god, you're right! Quick! We must dispose of all table salt! It's made of highly reactive sodium and extremely toxic chlorine!
What's that? The ocean is contaminated with trillions of tons of sodium chloride? Heaven help us, we're doomed!
In case you aren't getting it, I'm making fun of you. In case you didn't catch exactly how stupid I think you are, I'm guessing borderline retarded. At the very least you couldn't possibly have scored more than a 10 on the chemistry portion of your SAT.
One of the magical properties of nature is that when two parent atoms combine, they form a molecule that is in no way, shape, or form similar to either atom in its elemental state. To take a very related and familiar example (which I also used while mocking you) - the soft, silvery, and highly reactive metal sodium (it literally explodes on contact with water) and the incredibly toxic gas chlorine (a small breath of which can kill you) combine to form a very hard, non-reactive, non-toxic rock commonly known as white salt. Salts are very stable, and very non-reactive. They do separate out into ions in solution, but neither the sodium nor the chlorine are able leave the solution without pairing with its partner element, they are far, far too reactive - as soon as it is about to happen, the sodium will grab a loose chlorine ion or vice-versa. As ions they have interesting properties, like facilitating electron transfers (that's what makes salt water both conductive and allows it to oxidize iron).
Another neat property of atoms, especially those with either one or two valence electrons or six or seven valence electrons, is that they must always be bonded to other atoms (themselves, other atoms, it doesn't matter, they MUST be bonded). This is handy, because it keeps solid objects - a table, for example - from simply crumbling away into its individual atoms, like carbon. So while it seems that the Li and the CL have separated in the salt solution, in fact they remain bonded - there is no way to pull out the lithium from the solution without getting the Chlorine with it, and together they are non-toxic. It also happens to be significantly more difficult to form a lithium molecule, since it requires a half dozen lithium atoms, than it is to form lithium chloride, which requires only one lithium and one chlorine atom. The net effect is that lithium never, ever forms into lithium molecules if chlorine is anywhere nearby. Since they are in solution together, chlorine is available in perfectly balanced quantities.
Your straw man arguments fail to make us fall for it.
We did not talk about lithium chloride vapor to get into the atmosphere, but only lithium. We did also not talk about it having to be vapor. “Dust” suffices.
The only way to get lithium into the atmosphere from a lithium-chloride solution is as lithium chloride. It's not physically possible without some serious, serious heat and a lot of electricity.
Want to know how it's done? First, you have to melt the salt. Not an easy task - lithium chloride melts at 1200 degrees Fahrenheit. Once melted, all you have to do is pass a large electric current through it and the gas separates out, leaving solid lithium! Easy! Oh wait...
Now, what natural conditions in your neighborhood are heating things up to 1200 degrees and passing an electric current through them, I wonder? I can't think of any, and if you can, tell me, so I can stay the hell away. Anyway, find one, and dump the desiccant on it, and you'll have something to be concerned about. Otherwise it is not physically or chemically possible.
Now, who was it with the straw-man argument again?
Security is mostly a superstition... Avoiding danger is no safer in the long run than outright exposure. - Helen Keller