Chilled Water Cools MIT Physics Department
Here’s a very good example of simple tech that works efficiently. Because hot air rises, cool air falls down. So if chilled water is carried through tubes at the ceiling, it sucks hot air from a room; sending down the cooler air. Simple tech is often low carbon technology too.
- » See also: Paul Hawken on Being a ‘Doomer’
- » Get CleanTechnica by RSS or sign up by email.
Chilled beams use water to remove heat from a room. This is the opposite of radiant heating; in which pipes carry hot water in pipes embedded in a mortar for a stone or tile floor.
The potential reduction in fossil fuel use of using chilled beams instead of a traditional air conditioning system can be as much as 50%. “Chilled” is a bit of a misnomer; as the water doesn’t even need to be chilled. Even just running city water through this system will work as typical city water is about 55 degrees
Fahrenheit; enough to cool a 90 degree room. This works as a heat exchange.
If we used a system like this to cool every building we could achieve a cooling carbon reduction of 50% over 2009 levels. Fossil fuel use in heating and cooling buildings accounts for about 40% of our national carbon emissions.
This year’s climate bill contains incentives (Cap and Trade) for us to make reductions in fossil fuel use. Cap and Trade just means using fees (for choosing high carbon energy) to fund incentives (to help us buy low carbon energy).
The national building codes in the Climate Bill could do for the country what California building codes did for California: effortlessly cut our carbon footprint to half that of the nation: near European levels.
If you live near Boston, you can go check out how effective this innovative system is, and see if you can improve on the idea. The first installation is at MIT’s 49,000 square foot physics department; in buildings 4, 6, and 8, and next up is the new MIT Sloan School expansion and the David H. Koch Institute for Integrative Cancer Research.
“Chilled beams cool the people and dehumidify the air in the room. They take one-tenth the volume of fresh
air needed for traditional A/C, far less ductwork, smaller ducts, and smaller fans,” says David Cooper; manager of sustainability engineering and utility planning for the Department of Facilities.
This is a great passive cooling system for offices, laboratories, data centers and other spaces where equipment and sunlight generate a significant amount of heat.
“There’s a factor of eight improvement in cost of moving a Btu of air cooled by water versus air. If you can get the cooling energy into the space through water, you’re way ahead,” says Cooper. “The eight times factor is a very attractive alternative from an energy point of view.”
More ways to heat and cool our nation’s buildings to reduce our national carbon footprint:
Recycling waste heat from air conditioners
Airport with 40% lower fossil fuel
Very cheap DIY solar hot water
Very efficient solar hot water
Making energy from waste
Good idea. Perhaps it can integrate into a fire suppression system as well.
As many keep repeating, conservation of energy and reducing greenhouse gas production by efficiency and by reducing our levels of demand, are the easiest, least expensive, and fastest measures to cut global climate change and to save fuel for critical applications.
David - yeah. True, we frequently have little thin pipes of cold water in the ceiling anyway for fire safety. Just make them much bigger.
Another thing in HR4574 is expanded energy labeling like they have in Europe for cars (how many kg of co2 per kilometer)
Very successful:
http://greeninc.blogs.nytimes.com/2009/09/03/labels-consumers-and-efficient-tvs/
I wonder what happens to condensate from the air, and what happens to the slightly warmed water in the pipes.
Is this more of an “open-loop geothermal” system in which water is dumped in order to cool the air, or is it sort of opportunistically removing heat from rooms in the process of serving drinking, washing, & etc. water?
“The potential reduction in fossil fuel use of using chilled beams instead of a traditional air conditioning system can be as much as 50%”
What is the least amount of fossil fuel reduction?
Perpetually with the maxima, never the minima….
Very interesting. Does this significantly lower the temperature in a room? It sound very attractive and whats most interesting about it is its simple and not some huge thing that requires tons of investments.
Where and how does this system “unload” the the BTU’s that it picks up? Or does it just simply let the “warmed” water go down the drain?
Hope they pumped the warm water to ground heat storage for use as heating fluid at another time, or at least vent the heat through a means of recouping all that energy, possibly adequate for LED lighting of the entire building? We must develop win-win cycles as Mother Nature does, valuing sustainability and driving by natural forces such as night-time cooling, to win the energy war! The age of “Cheap Oil” is not over, the age of “Energy Folly” is! Replacing astute and precise engineering with the nonsense allowed by a pioneer society will go a long way in maturing the sciences and technologies of buildings! Super-insulations are under valued,poorly applied and rarely used, by fools who equate current energy costs against building costs using the assumption that oil is forever, at current prices! this “Easy Out” has made American engineers the laughing-stock of the world! Even Sweden re-uses its “cooling Tower” heat for example, but Yankee Engineering deems this as uneconomical using corrupt and logically wrong “Equations” to impress clients and fool the public, and they then rest on their laurels - as Japanese and Korean designs take over! Especially notable in car manufacture! Wake Up America, Last Call! Last Call!
I think in Mass. the temperature 10 feet below ground is about 55 degrees all year round.
That’s why they said the temperature of city water was 55 degrees. It seems like it is a shallow geothermal system.
Not enough info to think otherwise.
If you go below the dew point of the building interior there will be condensation and all sorts of moisture/mold problems.
In building my new home a Viessman rep was trying to sell me a ground source heat pump with ‘natural cooling’. The closed loop unit used the compressor only for capturing heat and for cooling you simply recirculated water through the system using the cooler ground temps to cool the recirculated water. No water wasted.
We have 60 degree ground water at our location. I rejected the system as ineffective in our location plus the condensation worries. Not to mention that ground source heat pumps are more costly due to the initial price plus wells.
Turns out that even on the hottest 100 degree day we have not turned on the AC system the first summer as there is almost always a cool breeze we catch as we are up on a hill.
I may be wrong but this sounds like a problematic solution to me.