RE: Drinking Water From Air Humidity
>Why doesn't the wind turbine count as a source of energy? Â It absolutely does. My question concerned how much energy per liter compared to other unconventional methods. >It's pretty obvious that when he said "none" he meant no _external_ source of energy. Well, since he was responding to my post, I stayed focused on the question of how much energy it took per liter of water produced...and wanted the reader to draw exactly the conclusion you did.the wind turbine was a source of energy. But, as I said elsewhere, in a remote location, even otherwise inefficient sources of necessities become relatively efficient compared to having stuff hauled zillions of kilometers. I neglected that point because I saw it, thought it reasonable and clear, and had nothing to add. But, I didn't know off the top of my head the relative energy efficiency vs. other techniques of getting fresh water from unconventional sources. So, I asked. Dan M. ___ http://mccmedia.com/mailman/listinfo/brin-l_mccmedia.com
RE: Drinking Water From Air Humidity
> -Original Message- > From: brin-l-boun...@mccmedia.com [mailto:brin-l-boun...@mccmedia.com] On > Behalf Of hkhenson > Sent: Monday, July 13, 2009 12:29 PM > To: brin-l@mccmedia.com > Subject: Re: Drinking Water From Air Humidity > > At 07:05 AM 7/13/2009, Dan M wrote: > > snip > > >Because it clearly won't work well at any time but the pre dawn hours in > >the desert. The collectors have to be cooled below the dew point. Let me > >give a US example. In Las Vegas yesterday, in the heat of the day, the > >temperature was 42C, while the dew point was -1C. Even shaded, it takes > >tremendous power to keep collectors that cold while deliberately being > >exposed to a very hot wind. > > Obviously they would not build them this way. Think about > dehumidifiers. In a damp basement this one will put out 33 l of > water a day on 750 watts > > http://cgi.ebay.com/FRIGIDAIRE-70-PINT-POWER- > DEHUMIDIFIER_W0QQitemZ330340172232QQcmdZViewItemQQptZLH_DefaultDomain_0?ha > sh=item4ce9cf01c8&_trksid=p3286.c0.m14&_trkparms=65%3A7|66%3A2|39%3A1|293% > 3A1|294%3A50 > > Dehumidification: 33.1 Litres/Day > > EEV (L/KW/H): 1.6 OK, would you agree that this is kinda a best case scenario? I've used dehumidifiers in damp basements, and the relative humidity was quite high 80+%. You're right about different deserts, I happened to pick Las Vegas because I've benchmarked the local NWS office, and Las Vegas temps for the last few days is just a few clicks from that bookmark. But, the UAE, for example, would be better offbut not as good as the basement. I also have numbers for the Perth desalinization plant, which quotes 3.2 kwH per 1000 liters. I have the website for them on another computer, but will bring it over if folks have trouble finding it. Now, this could be propaganda, but I have a hard time believing that they could lie about factors of >100 and get away with it. So, it looks like desalinization is much less energy intensive when salt water is available. That's probably why places like the UAE are looking at desalinization instead of condensers. Dan M. ___ http://mccmedia.com/mailman/listinfo/brin-l_mccmedia.com
Re: Drinking Water From Air Humidity
At 07:05 AM 7/13/2009, Dan M wrote: snip Because it clearly won't work well at any time but the pre dawn hours in the desert. The collectors have to be cooled below the dew point. Let me give a US example. In Las Vegas yesterday, in the heat of the day, the temperature was 42C, while the dew point was -1C. Even shaded, it takes tremendous power to keep collectors that cold while deliberately being exposed to a very hot wind. Obviously they would not build them this way. Think about dehumidifiers. In a damp basement this one will put out 33 l of water a day on 750 watts http://cgi.ebay.com/FRIGIDAIRE-70-PINT-POWER-DEHUMIDIFIER_W0QQitemZ330340172232QQcmdZViewItemQQptZLH_DefaultDomain_0?hash=item4ce9cf01c8&_trksid=p3286.c0.m14&_trkparms=65%3A7|66%3A2|39%3A1|293%3A1|294%3A50 Dehumidification: 33.1 Litres/Day EEV (L/KW/H): 1.6 I have not looked into one for years, but they have been built as counter current back to the 50s. The cold air dry air is used to cool the incoming air so the main energy drain is pumping out the heat from condensing the water. You are not going to get much water out of one on a hot dry day in Las Vegas. But there are deserts where the typical humidity is high, it just doesn't rain. Keith ___ http://mccmedia.com/mailman/listinfo/brin-l_mccmedia.com
Re: Drinking Water From Air Humidity
On 14/07/2009, at 12:18 AM, John Williams wrote: On Mon, Jul 13, 2009 at 7:05 AM, Charlie Bell wrote: On 13/07/2009, at 11:39 PM, John Williams wrote: If it takes a lot of energy to condense the water, then you need a large wind-turbine or a lot of solar panels. Depends how much water you need. And how much energy does it take to manufacture the wind-turbines or solar panels? Depends on the answer above. Would it have been more efficient to run a large-scale desalination plant somewhere else (perhaps with nuclear power?) and pipe the water to the needed location? Depends on how far you need to pipe it and to how many people. Those questions were meant to be taken together. Yeah, but splitting up the answer made sense to me... It does not depend on how much water (except for economies of scale) since the comparison is per liter of water produced locally by wind-turbine vs. produced elsewhere by other means. ...plus getting it there. So yes, knowing how much you need is part of it. So, a couple of wind units producing 10l/hr (5001/day, roughly - plenty for drinking and cooking, at least) each of potable water would go a long way towards lowering the cost (energetic and fiscal) of producing drinking water. How do you know they lower the cost? The wind units may cost more, per liter per year, than some other source. Well, I know that the comparisons that I saw at the time suggested that the total cost was less. Sorry, can't remember or find the figures right now. I guess that's a long-winded way of saying - need to look at every case on its own merits, which I guess is probably where you were headed too? More or less. I was just interested in comparing the cost of the wind-turbine or solar-panel system to something more centralized. Yeah, apologies for the lack of hard numbers right now. But I'm sure admitting I can't find them is better than making them up. :-) C. ___ http://mccmedia.com/mailman/listinfo/brin-l_mccmedia.com
Re: Drinking Water From Air Humidity
On Mon, Jul 13, 2009 at 7:05 AM, Charlie Bell wrote: > > On 13/07/2009, at 11:39 PM, John Williams wrote: > >> If it takes a lot of energy to condense the water, then you need a >> large wind-turbine or a lot of solar panels. > > Depends how much water you need. >> >> And how much energy does it take to manufacture the wind-turbines or >> solar panels? > > Depends on the answer above. > >> >> Would it have been more efficient to run a large-scale desalination >> plant somewhere else (perhaps with nuclear power?) and pipe the water >> to the needed location? > > Depends on how far you need to pipe it and to how many people. Those questions were meant to be taken together. It does not depend on how much water (except for economies of scale) since the comparison is per liter of water produced locally by wind-turbine vs. produced elsewhere by other means. > So, a couple of wind units producing 10l/hr (5001/day, roughly - > plenty for drinking and cooking, at least) each of potable water would go a > long way towards lowering the cost (energetic and fiscal) of producing > drinking water. How do you know they lower the cost? The wind units may cost more, per liter per year, than some other source. > I guess that's a long-winded way of saying - need to look at every case on > its own merits, which I guess is probably where you were headed too? More or less. I was just interested in comparing the cost of the wind-turbine or solar-panel system to something more centralized. ___ http://mccmedia.com/mailman/listinfo/brin-l_mccmedia.com
Re: Drinking Water From Air Humidity
On 13/07/2009, at 11:57 PM, dsummersmi...@comcast.net wrote: In other words, I'd bet a case vs. a bottle of beer that it's a lot prettier on paper than in practice as a means of providing, say, Las Vegas, with drinking water. Because turbines supply the energy doesn't mean that its energy efficient. I said it was for remote areas, and produced 10l/hr. Beyond that, the only information I had was what was on the ABC New Inventors website, and the video for that episode is no longer online, and the inventor's website, which is currently not very informative, although it was a lot more so before. Maybe archive.org will help. Anyway, a small self-contained unit (that was small enough to mount on a truck) that'll produce 10l/hr. No, condensation is not going to assist big cities. I apologise, but to me, desert means "not many people live there". I keep forgetting that you yanks build big cities in the middle of them and your response to "this'll provide water in the desert" is "great - we can play golf now" rather than "great, we're not going to die out here...". Different viewpoints entirely. C. ___ http://mccmedia.com/mailman/listinfo/brin-l_mccmedia.com
Re: Drinking Water From Air Humidity
On 13/07/2009, at 11:39 PM, John Williams wrote: If it takes a lot of energy to condense the water, then you need a large wind-turbine or a lot of solar panels. Depends how much water you need. And how much energy does it take to manufacture the wind-turbines or solar panels? Depends on the answer above. Would it have been more efficient to run a large-scale desalination plant somewhere else (perhaps with nuclear power?) and pipe the water to the needed location? Depends on how far you need to pipe it and to how many people. These are not rhetorical questions. I'd be interested in the answers if anyone knows them. Yep. Well, here's the situation at a place I've been - the roadhouse near the entrance to the Shark Bay World Heritage area. There are 6 permanent residents, 3 or 4 transient staff, and on any night there may be 30 or so visitors, mostly in caravans/campervans, a handful in the cabins of which there were 4 iirc. Probably 50 - 60 trucks a day go by. Some showers. A radio transmitter (booster station). Cafe in the roadhouse. This place is about 100 miles in each direction from the next similar roadhouse (doing this from memory, can't be arsed to find my journal). Water is bore water, and drinking water is provided by reverse osmosis powered by diesel generators. So, a couple of wind units producing 10l/hr (5001/day, roughly - plenty for drinking and cooking, at least) each of potable water would go a long way towards lowering the cost (energetic and fiscal) of producing drinking water. And piping water, at present, makes little sense. However, if the main water pipeline is built taking good quality water from the north at Lake Argyll or a similar dam project down to Perth is built, then suddenly branch pipes to towns and maybe along the main highway suddenly makes sense. Likewise, the energy, construction and piping costs of bringing water from a desal plant planned near-ish to Melbourne don't make sense compared to beefing up the water reclamation plant and using recycled water for the power station that currently uses 100 gigalitres a year of potable water (freeing up 100 gigalitres for drinking, which is what the desal plant is going to produce *facehand*), or even piping water across Bass Strait from where there is lots and lots (Tasmania) to where there isn't (Victoria). I guess that's a long-winded way of saying - need to look at every case on its own merits, which I guess is probably where you were headed too? Charlie. ___ http://mccmedia.com/mailman/listinfo/brin-l_mccmedia.com
Re: Drinking Water From Air Humidity
Original Message: - From: Charlie Bell char...@culturelist.org Date: Mon, 13 Jul 2009 19:25:51 +1000 To: brin-l@mccmedia.com Subject: Re: Drinking Water From Air Humidity Charlie wrote: >Read it again properly, and don't treat me like a first grader. I asked how much energy is required and you said none. I read the reply three times, an d at best the answer seemed to sidestep the question.as did every promotional piece on it. Having lived in a hot humid climate, and having gone through a month of humid weather with no rain, I have some feel for how energy intensive this process is in the middle of the day in Houston, where it is extremely humid. Far more humid than more deserts. >It's a WIND TURBINE. I said it was a wind turbine in my original post. Right, and there are wind turbines that passed me on the road capable of generating multiple MW per hour. I was trying to find out if anyone had numbers on the name plate capacity of the turbine vs. the liters per day. Because it clearly won't work well at any time but the pre dawn hours in the desert. The collectors have to be cooled below the dew point. Let me give a US example. In Las Vegas yesterday, in the heat of the day, the temperature was 42C, while the dew point was -1C. Even shaded, it takes tremendous power to keep collectors that cold while deliberately being exposed to a very hot wind. At the coolist hour, the temp was 28C, and the dew point rose to 4 C. At that temperature difference, with a perfect lossless system, roughly 10% of the total cooling has to be added as power. Between the cooling necessary to keep a panel cooling the atmosphere as it blows past it, and the energy emitted by the latent heat of vaporization, there's quite a bit of energy per liter involved. How much involves a lot of specifics. Inherently its the type of problem one usually solves by reading the specificationsbecause I'd have to guess a lot on the efficiency of the unit in only cooling the air it takes water out of and maximizing how much it cools it. For example, if the dew point is 2C and the condensor is 1C, one only takes the water that represents the water capacity of air at 2C vs. 1C out of the atmosphere. So, one would need to pick a lower tempbut how low depends on specifics, and is a days long enegeering problem. But, none of the promos offer specifications. >No external source of energy. Self contained. OK if you want to be >super pedantic you can say wind or light is the external source of >energy, but to me that means energy that has to be transported to site >like fuel or power lines. But, self contained electricity units are very ineffecient and thus expensive. In a sense, self-contained energy production is usually seen by the public as "not counting." But, if we were to compare its efficiency vs. desalinisation in energy/liter, we'd need to know the energy per liter numberssomething that's just not available. In essense, for this to work in the desert, it would have to cool condensors to below freezing to then cool the air below the dew point. And, this system would only work at all decently in the few hours before dawn if the wind was blowing hard. In other words, I'd bet a case vs. a bottle of beer that it's a lot prettier on paper than in practice as a means of providing, say, Las Vegas, with drinking water. Because turbines supply the energy doesn't mean that its energy efficient. Dan M. ___ http://mccmedia.com/mailman/listinfo/brin-l_mccmedia.com mail2web.com - Microsoft® Exchange solutions from a leading provider - http://link.mail2web.com/Business/Exchange ___ http://mccmedia.com/mailman/listinfo/brin-l_mccmedia.com
Re: Drinking Water From Air Humidity
If it takes a lot of energy to condense the water, then you need a large wind-turbine or a lot of solar panels. And how much energy does it take to manufacture the wind-turbines or solar panels? Would it have been more efficient to run a large-scale desalination plant somewhere else (perhaps with nuclear power?) and pipe the water to the needed location? These are not rhetorical questions. I'd be interested in the answers if anyone knows them. ___ http://mccmedia.com/mailman/listinfo/brin-l_mccmedia.com
Re: Drinking Water From Air Humidity
Charlie Bell wrote: > > Maybe I forgot to take into account the brainwashing that happened > when he entered the oil industry, and he can't see the words 'wind" > and "turbine" if they're adjacent to each other. Dan, is this words, > or a blank space: "WIND TURBINE" ? How about this? "RENEWABLE ENERGY"? > What is a "wind turbine"? What is "renewable energy"? Those words make no sense to me either, since energy = oil. Alberto Monteiro ___ http://mccmedia.com/mailman/listinfo/brin-l_mccmedia.com
Re: Drinking Water From Air Humidity
On 13/07/2009, at 4:31 PM, Doug Pensinger wrote: Dan M wrote: > None, once it's out there. IIRC, it's a small wind turbine that cools > collectors in it, and desert air is often humid even if it doesn't > rain much. If the collectors are cooled, there _has to be_ a source of energy that is being used. If not, then we've just found an exception to the 2nd law of thermodynamics. Why doesn't the wind turbine count as a source of energy? It's pretty obvious that when he said "none" he meant no _external_ source of energy. Maybe I forgot to take into account the brainwashing that happened when he entered the oil industry, and he can't see the words 'wind" and "turbine" if they're adjacent to each other. Dan, is this words, or a blank space: "WIND TURBINE" ? How about this? "RENEWABLE ENERGY"? Uh-oh. There's an oil truck pulling up outside. They're coming to the door. A... *message aborted* ___ http://mccmedia.com/mailman/listinfo/brin-l_mccmedia.com
Re: Drinking Water From Air Humidity
On 13/07/2009, at 10:13 AM, Dan M wrote: -Original Message- From: brin-l-boun...@mccmedia.com [mailto:brin-l- boun...@mccmedia.com] On Behalf Of Charlie Bell None, once it's out there. IIRC, it's a small wind turbine that cools collectors in it, and desert air is often humid even if it doesn't rain much. If the collectors are cooled, there _has to be_ a source of energy that is being used. If not, then we've just found an exception to the 2nd law of thermodynamics. Read it again properly, and don't treat me like a first grader. It's a WIND TURBINE. I said it was a wind turbine in my original post. No external source of energy. Self contained. OK if you want to be super pedantic you can say wind or light is the external source of energy, but to me that means energy that has to be transported to site like fuel or power lines. You can work out how powerful the wind turbine component needs to be to condense 10l/hr if that's an exercise you want to do, but the unit, as I said, requires no energy to run once it's installed. Charlie. ___ http://mccmedia.com/mailman/listinfo/brin-l_mccmedia.com
Re: Drinking Water From Air Humidity
Dan M wrote: > > > None, once it's out there. IIRC, it's a small wind turbine that cools > > collectors in it, and desert air is often humid even if it doesn't > > rain much. > > If the collectors are cooled, there _has to be_ a source of energy that is > being used. If not, then we've just found an exception to the 2nd law of > thermodynamics. > Why doesn't the wind turbine count as a source of energy? It's pretty obvious that when he said "none" he meant no _external_ source of energy. Doug ___ http://mccmedia.com/mailman/listinfo/brin-l_mccmedia.com
RE: Drinking Water From Air Humidity
> -Original Message- > From: brin-l-boun...@mccmedia.com [mailto:brin-l-boun...@mccmedia.com] On > Behalf Of Charlie Bell > > None, once it's out there. IIRC, it's a small wind turbine that cools > collectors in it, and desert air is often humid even if it doesn't > rain much. If the collectors are cooled, there _has to be_ a source of energy that is being used. If not, then we've just found an exception to the 2nd law of thermodynamics. A useful statement of the 2nd law for our purposes is that "it is impossible to transfer heat from a cooler reservoir to a warmer one without adding work of some kind. The sites I read said that a wind turbine, solar cells, or thermal solar heaters could be used. All are sources of low entropy energy. Now, one might thing that a solar heater is an exception to the rule, but it isn't. With it, one has three reservoirs. Hot, medium, and cool. The hot is the solar heater water, the medium is the environment and the cool is the collectors. One can simultaneously transmit heat from the hot and cool to the medium, the ratio of which is determined by the laws of thermo. If need be, I can still work out the problem analytically, but it's been a while since I did the actually number crunching. :-) Speaking metaphorically, there has to be a waterwheel of some kind driving the mechanism that pulls things uphill. >Even a cold beer at 3C attracts a lot of condensation. This > is definitely a small scale solution for remote locations. And it took work, probably from an electric motor, to make that beer cold. Now, if you have a cold reservoir available, then the thermo is simple, but I don't think that's what's being talked about. It definitely looks like work is involved. I suppose I could figure it out, but with a wife recovering from a second knee operation, keeping house, and working full time, I probably won't do the problem just for the fun of it. But trust me, some external, low entropy source of energy is needed. A wind turbine would qualify. In essence, all we would need to know is what the output of the wind turbine is, what the water production is, and we'd have our answer. > > It reminded me of your discussion of > > how energy intensive desalination is. > > Yeah, but that's a different process. Fair enough, but I'm guessing you'll find that it takes a lot more energy per liter of water than you might think to pull the water out of the air. > But look at how much water comes > out as a by-product of airconditioning systems... And look at how big my electricity bill is to run it. :-) Dan M. ___ http://mccmedia.com/mailman/listinfo/brin-l_mccmedia.com
Re: Drinking Water From Air Humidity
On 13/07/2009, at 4:26 AM, Dan M wrote: -Original Message- From: brin-l-boun...@mccmedia.com [mailto:brin-l- boun...@mccmedia.com] On Behalf Of Charlie Bell There are several devices to do this, some of them actually on the market. One is a wind turbine arrangement that produces around 10 litres an hour (plenty for drinking purposes for several people!). I looked at reports on this, although I didn't even bothering checking the website you mentioned because you said it was down. One think struck me, although they talk about being great because alternative energy sources can be used, there was no mention of the amount of energy needed per liter of water. None, once it's out there. IIRC, it's a small wind turbine that cools collectors in it, and desert air is often humid even if it doesn't rain much. Even a cold beer at 3C attracts a lot of condensation. This is definitely a small scale solution for remote locations. It reminded me of your discussion of how energy intensive desalination is. Yeah, but that's a different process. But look at how much water comes out as a by-product of airconditioning systems... Charlie. ___ http://mccmedia.com/mailman/listinfo/brin-l_mccmedia.com
RE: Drinking Water From Air Humidity
> -Original Message- > From: brin-l-boun...@mccmedia.com [mailto:brin-l-boun...@mccmedia.com] On > Behalf Of Charlie Bell > > There are several devices to do this, some of them actually on the > market. One is a wind turbine arrangement that produces around 10 > litres an hour (plenty for drinking purposes for several people!). I looked at reports on this, although I didn't even bothering checking the website you mentioned because you said it was down. One think struck me, although they talk about being great because alternative energy sources can be used, there was no mention of the amount of energy needed per liter of water. It reminded me of your discussion of how energy intensive desalination is. It both makes sense and is interesting how dependent so many things are on the availability of energy in low entropy states. Because, if it was just energy we needed, all we would need to do was tap the tremendous energy in the heat of the atmosphere or the oceans. Dan M. ___ http://mccmedia.com/mailman/listinfo/brin-l_mccmedia.com
Re: Drinking Water From Air Humidity
On 7/12/2009 1:53:34 AM, Charlie Bell (char...@culturelist.org) wrote: > On 12/07/2009, at 3:42 PM, Warren Ockrassa wrote: > > > On Jul 11, 2009, at 7:03 PM, Charlie Bell wrote: > > > >> There are several devices to do this, some of them actually on the > >> market. One is a wind turbine arrangement that produces around 10 > >> litres an hour (plenty for drinking purposes for several people!). > > > > Vaporators? My first job was programming binary load lifters. Very > > similar to your vaporators in most respects... > > *chuckle* Uh-huh. > Lol...the first time I saw Star Wars I kept seeing lifts from Dune too. xponent Sand People Maru rob ___ http://mccmedia.com/mailman/listinfo/brin-l_mccmedia.com
Re: Drinking Water From Air Humidity
On 12/07/2009, at 3:42 PM, Warren Ockrassa wrote: On Jul 11, 2009, at 7:03 PM, Charlie Bell wrote: There are several devices to do this, some of them actually on the market. One is a wind turbine arrangement that produces around 10 litres an hour (plenty for drinking purposes for several people!). Vaporators? My first job was programming binary load lifters. Very similar to your vaporators in most respects... *chuckle* Uh-huh. C. ___ http://mccmedia.com/mailman/listinfo/brin-l_mccmedia.com
Re: Drinking Water From Air Humidity
On Jul 11, 2009, at 7:03 PM, Charlie Bell wrote: There are several devices to do this, some of them actually on the market. One is a wind turbine arrangement that produces around 10 litres an hour (plenty for drinking purposes for several people!). Vaporators? My first job was programming binary load lifters. Very similar to your vaporators in most respects... -- Warren Ockrassa | @waxis Blog | http://indigestible.nightwares.com/ Books | http://books.nightwares.com/ Web | http://www.nightwares.com/ ___ http://mccmedia.com/mailman/listinfo/brin-l_mccmedia.com
Re: Drinking Water From Air Humidity
On 16/06/2009, at 2:22 PM, net_democr...@yahoo.com wrote: "In the seminal science fiction book 'Dune,' Frank Herbert envisioned the Fremen collecting water from the air via moisture traps and dew collectors. Science Daily reprints a press release from the Fraunhofer Institute in Stuttgart, where scientists working with colleagues from Logos Innovationen have developed a closed-loop and self-sustaining method, no external power required, for teasing the humidity out of desert air and into potable water." http://www.sciencedaily.com/releases/2009/06/090605091856.htm There are several devices to do this, some of them actually on the market. One is a wind turbine arrangement that produces around 10 litres an hour (plenty for drinking purposes for several people!). http://www.waterunlimited.com.au/ is one, although their website seems to be in between designs right now. C. ___ http://mccmedia.com/mailman/listinfo/brin-l_mccmedia.com
Drinking Water From Air Humidity
"In the seminal science fiction book 'Dune,' Frank Herbert envisioned the Fremen collecting water from the air via moisture traps and dew collectors. Science Daily reprints a press release from the Fraunhofer Institute in Stuttgart, where scientists working with colleagues from Logos Innovationen have developed a closed-loop and self-sustaining method, no external power required, for teasing the humidity out of desert air and into potable water." http://www.sciencedaily.com/releases/2009/06/090605091856.htm ___ http://mccmedia.com/mailman/listinfo/brin-l_mccmedia.com
