New Heating Technology Uses Seawater and Carbon Dioxide (csmonitor.com) 155
Kenneth Stephen writes: While some enterprises have used sea-water for cooling, others are starting to use this for heating. and thereby cut back greatly on the carbon footprint of large facilities. What makes this technique even more fascinating is that a key component of this technology is carbon dioxide — the greenhouse gas that has climate watchers so worried.
An Alaska aquarium recently announced "the first installation of CO2 refrigerant heat pumps to replace oil or electrical boilers in a conventional heating system in the United States" after 7 years of development, and predicts they'll now save up to $15,000 each month on their heating bill.
Good news (Score:1)
Well, that's good news.
Re: Good news (Score:5, Insightful)
> thousands of times more than the negligible amount mankind has ever produced
nice try.
the yearly production of CO2 by humans is MUCH higher than the yearly CO2 production by volcanoes.
from first link I found :
-->volcanoes release a total of about 200M ton of CO2 annually.
-->global fossil fuel CO2 emissions (2003) = 26B ton CO2
Distraction (Score:5, Insightful)
The Key takeaway here is saving $15k a month on heating bills.
If the savings are representative or what can be achieved elsewhere, the economics and payback period work out, then it's a Win-Win.
The surest way to bring someone over to your Environmentalists side is to show people they can save lots of money. Haranguing them about the CO2 and driving up energy costs...not so much.
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How do I convince the city to let me have a couple small roof top wind turbines? Apparently I can have an attic ventilator but if I connect a generator to it suddenly it harms the wild life and is unsightly therefore not allowed.
Re:Distraction (Score:4, Insightful)
It's ALWAYS better to ask forgiveness than permission.
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About the time I was ready to grid-tie they would say you can't have that remove it and I would be out a bunch of money.
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Pay off the inspector. It's the american way. Kinda seriously.
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Implement the grid-tie as a portable system which plugs in instead of a fixed installation.
I know of a case in Los Angeles County where they were building a mountain top transmitting location and when they went to install the transmitters, the county told them they needed separate permits for each fixed installation and that it would take months to process the paperwork. So the solution was to put all of the equipment racks on rollers and add extension cords and outlets so they could be plugged in for powe
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I said "people"
To paraphrase Agent K:
"People are smart. People in Government are dumb, stupid animals bereft of common sense and imagination."
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Well I'm sure it doesn't make anymore noise than the 9ft tall windmill lawn art that does squat but spin, there are half a dozen in my neighborhood and with an average wind speed of 14.5 mph they spin a lot. I would need to remove a bunch of trees and spend about 8 times as much to get the same out of solar so much that I would make back my investment a couple years after I had to replace them.
How does the thermodynamics work? (Score:2)
I've never fully understood how the thermodynamics works out when you run the heat pump in the counterituidive direction.
Normally one uses a heat pump to take heat from a hot object and transport it to a cold object. this is intuitively obvious. the heat pump is, logically, just like a fan accelerating the transport of what was going to happen eventually anyhow.
I also can see how these can work past that logical point when you are using it as an airconditioner. It creates a cold object in the room, colde
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The heat pump is better than resistive heating by the amount of outside heat it can pump in. It's just a matter of turning the air conditioner around. It exhausts the heat from the energy it uses into the room, which is the equivalent of resistive heating, and moves heat from the colder outside to the warmer inside. It isn't going to work very well if it gets really cold outside (say 0F/-20C/253K), because it's difficult to make the outside spot colder than the outside, and at that point it's basically
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People who have internalized so much right-wing propaganda that they've become totally delusional are very confident in their beliefs, because Conservatism has become a cult. They consider science and news "Liberal" and embrace superstition and propaganda. They're probably hopeless, but you're doing good work in correcting the propaganda when they regurgitate it outside their bubble.
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There are at the moment over 30 volcanoes erupting world-wide spewing millions of tons of CO2 into the atmosphere, thousands of times more than the negligible amount mankind has ever produced starting with the very first fires of cave-men
Even without knowing exactly how much CO2 the volcanoes produce you can already see that this is not right. Volcanoes have been producing CO2 since the beginning of the Earth, yet the CO2 concentration in the atmosphere only started to go up since the industrial age. Also, when you look at the graph of CO2 concentration, you see a nice smooth rise, and no sudden peaks during years of massive eruptions.
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Which graph [wikipedia.org], has no peaks? See that graph where CO2 levels keep dipping down toward 180ppm 4 separate times; if it had dipped to 150ppm, life on Earth would have ended. Perhaps these graphs [google.com] that show CO2 levels as high as 17 1/2 times higher than today maybe; are those the ones that only show "the CO2 concentration in the atmosphere only started to go up since the industrial age"?
Of course if volcanoes were only the massive eruptions that make the TV news and Hollywood disaster movies, you would have a poin
Re: Good news (Score:5, Informative)
Which graph [wikipedia.org], has no peaks?
This one: http://www.esrl.noaa.gov/gmd/w... [noaa.gov] I do want to clarify my earlier statement. Obviously, CO2 has varied in a lot in the past, but looking at your Vostok graph, it has been relatively slow moving for the last half million years, never crossing 300 ppm. Since the industrial age, we've crossed 300 ppm, quickly followed by breaking the 400 ppm level, even though volcanic activity isn't remarkable.
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That graph is only about 60 years long, the "Industrial Age" is generally assumed to have been from 1850 to present; that graph doesn't even go back before AGW was theoretically possible, 1950.
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fine;
That graph is only about 60 years long, the "Industrial Age" is generally assumed to have been from 1730 to present; that graph doesn't even go back before AGW was theoretically possible, 1950.
I stand corrected, I was giving undue credit. Even though when Industrial age is spoken of in a climatological context, it refers to 1850 when the major climatological datasets begin.
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You seem to make numbers up... but luckily real numbers exist. The American geophysical union (which includes many of the world's foremost experts on volcanoes) actually calculated how much CO2 volcanoes produce in an average year, the answer is about 0.25% of what coal power plants put out in an average year (and that's only a fraction of industrial CO2 emissions - remember cars for example).
Volcanic CO2 emissions average a quarter of a percent of coal powerplant CO2 emissions. We outdo volcanoes all the d
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I really didn't read "at the moment" as being an accumulated number.
Dangerous (Score:1, Funny)
Carbon dioxide is a trace gas in the atmosphere. If too much of this is done, we'll run out of carbon dioxide. That will kill plants and make the Earth a very cold place. This seems like a bad idea to me.
Re: Dangerous (Score:5, Informative)
CO2 is just the refrigerant. It is not consumed by the heating cycle. CO2 has been used for cooling in many places, this is the first I've heart of using it in a heat pump for heating though.
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You can think of a heat pump as a reversible refrigerator. In cooling mode, it works just like a refrigerator: the compressor compresses gas, lets it radiate heat of compression outside, then pumps it inside to evaporate.
The remarkable thing is that you can turn the process around to heat the inside instead of the outside. You compress the gas outside to make it hot, then pump it inside to release that heat. A carefully-designed valve causes it to go from liquid to gas, or reverse, depending on where you wa
Re: Dangerous (Score:3, Insightful)
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Carbon dioxide is a trace gas in the atmosphere. If too much of this is done, we'll run out of carbon dioxide. That will kill plants and make the Earth a very cold place. This seems like a bad idea to me.
We could take out 100 ppm of CO2 and return back to pre-industrial levels. That's 780 gigaton of CO2 (even more when you consider that the oceans will release some too). As a comparison, we only have about 200 gigaton of proven oil reserves left. So, tell me, what should we be more careful of ? But you needn't worry at all, because the required CO2 isn't going to be removed from the atmosphere. They'll just make some new.
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Maybe if we could complete the cycle, convert CO2 back to long chain hydrocarbons, we'd be good indefinitely.
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It's not an example of switching "from fossil fuels toward innovative clean energy". It's an example of switching from an inefficient heating technology (electrical resistance heating) to a more efficient heating technology (refrigeration). Presumably the energy source is still fossil fuels because they likely want to heat the place on days and nights when the wind isn't blowing (not much solar at 60N in December).
It's also an example of wildly inaccurate reporting. But you can find wildly inaccurate rep
Re:Dangerous (Score:4, Informative)
Presumably the energy source is still fossil fuels because they likely want to heat the place on days and nights when the wind isn't blowing (not much solar at 60N in December).
The energy source is the difference between the temperature of the seawater (the heat source) and that of some other heat sink (probably the Alaskan air). Heat is collected from the ocean via a titanium heat exchanger, transferred to a glycol-water mix (i.e. antifreeze-laden water), and moved to a refrigerator operating as a heat engine - which then drives a heat pump to heat air warmer than either the ocean or the heat-sink air (or whatever).
The "news" is that they modified the heat engine to use liquid/gas carbon dioxide as a replacement for its original working fluid - R-134a (the pricey modern refrigerant that replaced the R-12 "freon" of ozone-hole fame).
Re:Dangerous (Score:4, Informative)
You still need energy to drive the compressor. Maybe that's what he means?
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You still need energy to drive the compressor. Maybe that's what he means?
As described it's a heat engine. It gets the energy from extracting heat from ocean water and dumping it somewhere else at a different temperature. This provides energy, which "drives the compressor" or the equivalent.
It's like the ammonia-cycle refrigerator as used in travel trailers, which uses heat from a flame (or an electric heater) to boil ammonia out of water at high pressure, cools it with a radiator, and uses this energy to
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The savings cited are over using e
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However, these new-fangled transcritical CO2 heat pumps tend to have a higher coefficient of performance than older ones based on ammonia or other HCFC-based working fluids. So, while you still need to supply (fossil fuel-based electrical) energy to get the thing to run, you need less of it with this machine. So, I call that progress and won't harangue them for an attention-grabb
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anybody building this without that grant is looking at about 4 years to recover their costs.
No! Almost no one would recover their costs that quickly, if at all. They key point is that this is in Alaska where nearly everything is extremely expensive. Nearly anywhere else, it would be insane to use fuel oil for heat. Instead, you would use cheap natural gas, or co-generated steam from a coal boiler, or a conventional heat pump.
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I assumed when they said 'used' it was consumed or converted in some manner as well. Not the case.
Used means "utilized" more often than "consumed" (though it can be both, or either). You picked a very odd way to take the original statement, almost as if you wanted it to be wrong.
They didn't really go into much more detail but assuming no maintenance anybody building this without that grant is looking at about 4 years to recover their costs.
The cost to the ASLC was $118,360. Saving $15k per month, it has an ROI under 1 year. Why are you trying to make a good thing look as bad as possible?
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The cost to the ASLC was $118,360. Saving $15k per month, it has an ROI under 1 year.
They state the savings may be as much as 15K in a month, but that is likely only during the mid winter months, there may be little or no savings in other months. Also, the savings are over old oil-fired boilers, and they don't seem to account for the added electrical bill they will see, so I'd say they are being purposefully optimistic with those savings statements (its PR after all). They may have saved more moving to a natural gas system if that was an option.
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The capital for that would have been higher, to make a personal gas-fired power plant.
Actually, gas retrofit of an oil boiler would be very cheap. You make a good point about gas availability, but that is the only factor that would make it a less desirable option from a cost standpoint. Shipping LP would even be a lot cheaper than oil fired.
The savings are clearly comparing the new cost against what they used to pay, not some other option.
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Generating 4kW cooling from 1kW electricity is common for domestic air conditioners. That you are dumb doesn't mean it violates thermodynamics. Learn what a heat pump is and how it works before stupidly correcting others.
KW is not energy or work. KW over time is. You don't get more work out of a system than you put in to it, it would violate the basic laws of physics. You should have paid attention in class.
100% efficiency is the highest energy efficiency achievable, it is the ideal and even this system will not approach 100% efficiency.
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Oh, and for correcting others incorrectly, you should probably use the terms correctly. It's not Kelvin-Watts.
You don't get more work out of a system than you put in to it, it would violate the basic laws of physics. You should have paid attention in class.
You should have paid attention in class. "System" is undefined, and you are assuming (incorectly) what it is. You are pretty danmed stupid for correcting people so incorrectly. The only one here that has no idea of what they are talking about is you. But I'm sure you will come
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Then how would you describe a system that got 4 kW of cooling from 1 kW of power? 4 kW of heating from 1 kW of power?
You should try to explain how you can, and then the basis for it. Theoretically, a system could output at 4KW for 1 hour if it had stored the equivalent energy of 1KW over 4 hours input. That would be 100% efficient, but you don't more out than you put in. If that were possible, all our energy problems would be solved.
But I assume when you say '4KW cooling from 1KW electrical' you don't really understand what you mean, and are mixing terms from two different aspects of a design. You can run a 4 KW motor
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But I assume when you say '4KW cooling from 1KW electrical' you don't really understand what you mean, and are mixing terms from two different aspects of a design.
So you are too stupid to understand, and too stupid to Google, and thus conclude I'm stupid for saying something you don't understand. That's brilliant. You must be the smartest person in the world.
Try reading these two links and let us know how that goes for you. Presumably, if you have an issue with Wikipedia, you can edit it be
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Ok, enough. You don't have an engineering or physical sciences background, that is clear.
I have an engineering degree. Do you?
You skim google searches and assume you understand what you are reading.
You don't skim anything and declare that makes you smarter than people who have researched topics.
You use terms that make no sense like "a Kw of cooling", which any engineer will tell you makes no sense.
Don't use quotes unless you are actually quoting. "a Kw of cooling" was never said by me. For one, I know that kilo is a lower case "k", something you've apparently never figured out. And a Kw isn't a unit of anything. So if you are going to quote someone, actually quote them. And even if you meant "kW" (which, given you've never managed to successfully write it correct
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COP is not efficiency, it a measure that reflects efficiency. Read this, from the same wiki source you linked to;
While the COP is partly a measure of the efficiency of a heat pump, it is also a measure of the conditions under which it is operating
and if you click on the link for thermal efficiency and look under COP you will find;
The reason for not using the term 'efficiency' is that the coefficient of performance can often be greater than 100%
Efficiency cannot be greater than 100%, hence the reason they included that statement. You can find similar statement elsewhere if you look for them.
But I now think I see where you are confused. Efficiency measures the energy put into and then taken out of the
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Efficiency cannot be greater than 100%, hence the reason they included that statement. You can find similar statement elsewhere if you look for them.
Not because it isn't true, but because pedantic assholes who can't understand complex thoughts whine endlessly about it.
But I now think I see where you are confused. Efficiency measures the energy put into and then taken out of the system,
I'm not confused. You are wrong on that, like everything else. Define the system. For a homeowner, the "system" is their home. They put in 1 kW electricity and get out 4 kW of heat. That's 400% efficiency. But that violates thermodynamics!
No, you pedantic idiot. Thermodynamics has one (And only one) system. The Universe. I hope you've heard of that system. It's where you keep al
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BTW, Kelvin*Watts is not a unit. It is two units multiplied. There is no such standalone engi
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Efficiency is max at 100%,
So if I can run a resistive heater and get 1kW of heat from 1 kW of electricity, one would call that 100% efficient.
Are you with me so far?
Then, you replace that with a heat pump and you input 1 kW of electricity and get 4 kW of heat, what would you call that?
You get more out than you put in.
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In the heat pump case you cited, electrical energy is used to move heat. We don't know the efficiency because we don't know how much heat energy was put into the system. If the efficiency was 100%, then the movement of "4 kW" (again, wrong unit but wtf) of heat energy would
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The difference is,
I didn't ask the difference. I asked how to describe it.
Since you claim EE (doubtful, given your lack of grasp of the topic, but likely given your pedantry and assertion of expertise in something you don't know anything about), I'll put it in EE terms.
Define "broadband". Read the FCC's definition of broadband. Go on, do both of those and get back to us.
If you ignore the heat energy put into the system from outside, it appears you are creating heat with the electrical energy.
The only person ignoring the energy put into the system from the outside is you. You are asserting that I'm wrong because when you do it wrong, it's wr
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If not, then you are just lying to come up with more non sequiturs to hide the fact that you now realize you are 400% wrong.
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So, if I said KwH, then you'd have agreed that they are 400% efficient? If not, then you are just lying to come up with more non sequiturs to hide the fact that you now realize you are 400% wrong.
No, because I completely explained, using kilowat-hours, the reasons why. I did it multiple times, but you simply don't get it. And, btw, for someone who gets on my case for capitalizing the unit improperly, I see you are not so consistent in that regard either. Welcome to the club.
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The ASLC will continue to save money and emissions using the more than $1-million setup; the aquarium estimates tens of thousands of dollars in energy savings annually and a carbon output cut of 1.24 million pounds per year.
That make breakeven, not including the cost of money, in multiple decades.
Re:Dangerous (Score:4, Insightful)
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And yet, I've been involved in numerous construction projects where a payback of more than 3 years would not even be considered. My boss once explained it to me that they have a fixed budget, don't have any capital available to go above that, and are taking a risk that has a non-negligible chance of going bankrupt within 3 years, anyway.
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Four years to recoup a capital investment is beyond fantastic. Even double that, as will be more likely when everything is figured in, is really good.
That's not going to happen in 4 years, using supercritical CO2 as a working fluid is difficult and the aquarium is going to be an engineering guinea pig. We'll learn a lot of things refine the process, slowly it'll get closer to being ready for prime time, and just when we really know how and when to do it; everybody will be gun-shy of it.
The other possibility is the Eco-nazis will decide the extra cold being dumped in the ocean is pollution and all the whackos will get all NIMBY about it.
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Rather than assuming no maintenance, you could assume the maintenance is included in the cost of operations.
Gonna need more details, doc... (Score:3, Insightful)
Especially this bit about compressing the CO2 to over 2,000 psi to heat it. I assume this process is powered by fairy dust, unicorn farts, politicians speaking honestly, or some other such magical limitless power source? This is Slashdot - give me the physics, not the fluff piece.
Re: Gonna need more details, doc... (Score:4, Informative)
Article is dumb.
The real news is buried. Google "transcritical CO2" to get the real story.
Requires cold water to work (Score:2)
Sounds like it makes sense in Alaska where the water is presumably already cold during the winter. http://www.industrialheatpumps... [industrialheatpumps.nl]
Re: Gonna need more details, doc... (Score:2)
I appreciate your heartfelt rant but this article has nothing to do with fossil fuels. It's about substituting a different refrigerant in a heat pump system to make it cheaper.
You might want to save that rant for a more appropriate thread.
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Its exactly how a fridge works.
when the compressor in your fridge compresses the coolant it gets warm, and then goes to the radiator on the back to cool down. Then when it is allowed to expand again inside the fridge it gets cold.
Nothing new about this technology at all. Same science that is behind fridges and airconditioners the world over.
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Except the part where CO2 needs 2000psi to achieve the phase transitions, would be a bitch if you lost pressure and the pipes filled with sublimated CO2.
I suppose if you can afford the high pressure pumps, pipes and fittings, then the thermal efficiency of the cycle starts to pay off.
Re: Gonna need more details, doc... (Score:1)
Eh, the pressure isn't that big a deal, and the German automakers are getting into it too, after they decided to pass on using R-1234yf.
That it is non-flammable and non-toxic adds to the benefits, especially in car accidents.
Re:Gonna need more details, doc... (Score:5, Informative)
The pressure really isn't that big of a deal. 2000PSIG sounds high, but industrially speaking that's not terribly impressive. To put it into perspective, CO2 storage cylinders are often 1800 PSIG.
Compressed natural gas as a vehicle fuel is 4000PSIG Max. Compressed hydrogen storage is 5000-10000PSIG.
More importantly, it's not the max pressure that's the important metric but the differential pressure. You wouldn't be compressing it from atmospheric pressure - the MINIMUM pressure in the system is going to be somewhere around 400PSIG.
Of course, this prompts an important question: Where the hell did "2000 PSI" come from? Existing commercial trans-critical CO2 refrigeration operates at ~1300PSIG, so either the designers of this system have determined there's a good reason to go all the way up to 2000 or there's some journalist math/sensationalism going on here... 2000 PSIG is typically the relief valve setting, so maybe that's the confusion.
=Smidge=
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Some people are pretty comfortable throwing around 3000psi SCUBA tanks, too - but their "high pressure" hoses run closer to 150psi, IIRC - the regulator is right on top of the tank. It's all very do-able, but a pretty steep departure from freon based stuff and the pressures it needs.
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Hell, aren't scuba tanks 3000 psi?
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At 2,000 psi, there are no phase transitions between liquid and gas.
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pressure + seawater + CO2 + hydrogen ==> NaCl + CH3CH2OH ?
Scientists just invented a foolproof method for creating moonshine. Yay, climate change!
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Looking through it, It's basically a new variation on a heat pump that's capable of higher efficiency at a higher temperature differential.
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This is a pond-loop geothermal system with CO2 as the coolant. Compared to resistance heating the water it's going to be much more efficient, and - in Alaska especially - it's going to be more efficient than an air-based system as you won't be working against sub 20F temps for a good portion of the year. But the power to run the system is all electric, which means it's coming from traditional sources (and by traditional I mean both fossil based and renewable sources).
The article, however is clearly powered
Isn't this a huge mini split? (Score:4, Insightful)
Feel free to point out if I'm wrong.. But, isn't this just like a huge mini split? Using CO2 instead of um.. Freon, or whatever they put in them these days?
Stick a huge finned thing out in the ocean, cycle some refrigerant around it, transfer heat from one side to the other? Requires electricity and it's not like.. you're *consuming* CO2 and removing it magically?
The article seemed to describe exactly what the mini-split in my living room does, only on a much higher scale, and with C02 as the transport medium instead of some other rare gas?
yes. (Score:2)
I'm not sure why it's such a big deal. While CO2 heat pumps are new-ish, they aren't groundbreaking.
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But compressing gas to almost 2000psi has me wondering what kind of compressor they using?
Most likely a variant on the scroll compressor, https://en.wikipedia.org/wiki/Scroll_compressor [wikipedia.org]...
Toxicity? (Score:2)
My first thought was "CO2 as a refrigerant - its kind of toxic isn't it? I wouldn't want to be around if a pipe broke."
Then I thought "Ammonia is also used as a commercial refrigerant, and that is also toxic. Which is worse?"
I haven't found any good answer online. Nobody seems to want to talk about toxic concentrations of ammonia in air, just in blood. Then there are all sorts of other complications - what quantities and pressures would be used for comparable CO2 and NH3 refrigeration plants? Does the lower
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Interestingly this last link refers to CO2's 'low toxicity'.
Well, CO2 isn't really that toxic. You'll die if you breath in pure CO2 anyway though. But that's because you'll suffocate since it is heavier than air and therefore remain in your lungs and prevents any new oxygen-rich air from entering.
It will also fill up closed spaces like basements and you'll basically drown in it.
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It's really hard to tell how toxic CO2 is. Healthy adults can tolerate a lot of it in environments like submarines. It looks like the values for Lethal Concetration (90,000ppm), Recommended Exposure Limit (5000ppm), etc are more WAGs than anything definitive. Some people react to CO2 at lower values than the REL (as low as 2000 ppm IIRC) but they don't curl up on the floor and die or anything like that. It'd probably be useful to know the lowest level that the most susceptible individuals can tolerate c
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"It reacts reversibly with water (in your blood) to produce carbonic acid"
Apparently not. CO2 in the blood is transferred as bicarbonate HCO3- not carbonate CO3--. The transfer is between CO2 and bicarbonate is done by red blood cells in the lungs. i.e. Atmospheric CO2 doesn't interface dirrectly to and dissolve in blood (at least not to any great extent)?
Not that it's clear that there's no problem. For one thing there's the issue of where the O and H in the bicarbonate come from. If it's from water, t
Re:Toxicity? (Score:4, Informative)
CO2 levels [inspectapedia.com] need to be above/around 50k ppm, or 5%, before it starts becoming a real danger. You'll know something is up long before that, around 1-2%.
Ammonia, [wikipedia.org] on the other hand, is considered lethal at 500 ppm, or 0.05%
I'm going to go with 'CO2 is at least 1/100th as toxic as Ammonia'. The CO2 displacing the O2 is a bigger concern, but still 'solvable' by getting out of the room.
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With death by CO2, it'll probably be fairly unpleasant, because your body's breathing regulation is governed largely by the concentration of CO2 in the blood. If there is too much CO2 in the ambient air, the CO2 in your blood can't be expelled through the lungs, and eventually you'll become acidotic and die. If you are lucky, you'll lose consciou
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The one saving grace is that ammonia smells quite distinctively, and at levels well below serious risk, so you'll at least know that there's a problem. CO2 is odorless, so you may not know that you are having a problem until your vision starts to cloud and your chest gets tight.
You'll probably notice your breathing pick up and feeling like you're not getting enough air. The body doesn't track O2 levels, it tracks CO2. Increased CO2 concentrations trips the body's responses to increase respiration. It doubles, for example, at 1% CO2.
Stick some sensors around the system that set off the fire alarms if CO2 goes high. Done.
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The Anhydrous Ammonia SDS [airgas.com] just says "Get medical attention immediately" over and over, then "Causes serious eye damage. Liquid can cause burns similar to frostbite." over and over a few times, then throws in a few "Causes severe burns. "; so I guess it's pretty toxic. I didn't see a CA prop 25 warning so I guess it just fucking kills before it causes reproductive harm or cancer, but I didn't look real good.
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Somebody is going to complain (Score:2)
I'm predicting that somebody will complain that using seawater is going to change the "natural" temperature of said seawater and will therefore affect the flora and fauna in the water and therefore humans are evil usurpers of the planet.
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I mean, what do you think it costs to heat a giant building each month in Alaska?
Re:Missed the point (Score:5, Informative)
The advantage of CO2 is that it is neither flammable, ozone damaging, high GWP, nor significantly toxicity. The disadvantage is that substantial re-designs of refrigeration systems are required to use it, as well as some changes to operation/maintenance.
The transition from R-12 to R-134a, is near drop-in, with only minimal redesign required for optimal performance. To switch to R-1234yf, the re-design required is relatively modest (pressures are higher, so a different pump is needed), but otherwise the principles and basic system architecture are the same. With CO2, you are dealing with transcritical fluids, and this requires a significant architectural change to the refrigerant circuit (as there is no condensation of the refrigerant, so no liquid refrigerant in the circuit).
Re: (Score:2)
Re: (Score:3)
So if the boiler breaks now you flood your house with CO2 and kill everyone in it? Doesn't sound like a good idea to me.
Flooding your house with any inert gas - like the fluorocarbons typically used in AC units and refrigerators - will only kill by displacing oxygen. It takes a lot to do that in a whole building, though if it were releases into an enclosed basement a hazard is far more likely. How often have you heard about deaths from this cause?
Still, lots better than flooding your house with compressed ammonia, sulfur dioxide, or methyl chloride which were used in refrigerators in the early 20th century, and did kill peop