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New Heating Technology Uses Seawater and Carbon Dioxide (csmonitor.com)
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.
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.
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.
> 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
Yes, I'm left. You have a problem with that?
Traditional refrigerants like R-12 (dichlorodifluoromethane) have massive ozone destruction capability, 1st generation replacements like R-134a (1,1,1,2-tetrafluorethane) has minimal ozone destruction capability but very high global warming potential (thousands of times more potent than CO2, gram for gram), 2nd generation replacements like R-1234yf (2,3,3,3-tetrafluorpropene) while having no ozone destruction capability and minimal global warming potential suffer from being highly flammable, increasing the risk of leaks.
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).
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=
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.
When Fascism comes to America, it will call itself Anti-Fascism, and tell you to give up your guns.
Which graph [wikipedia.org], has no peaks?
This one: http://www.esrl.noaa.gov/gmd/w... 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.