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“Cold Tube” cooling system uses half the energy of an air conditioner

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Re: “Cold Tube” cooling system uses half the energy of an air conditioner

#41

Post by CarbyAu »

eggsnbacon1 wrote: post #13
sparker72678 wrote: post #7

> The notoriously bad energy efficiency of air conditioners Air conditioners are actually pretty fantastically efficient for what they do. The problem with air conditioners is that there's no way to move a ton of heat without using a lot of energy. So, they do use a lot, but they make the most of it. What's truly bad are our buildings that have the minimal insulation and sealing possible, leaking all that cold air ri…

New buildings are rather efficient in US. The problem is old buildings that use 5X the energy for HVAC. I echo that AC is quite efficient. Far more efficient than traditional heating. There's a misconception that hot areas are less environmentally friendly due to AC. The opposite is true. Hot areas are only 25 freedom units hotter than humans prefer. Cold areas have months of 50+ temperature difference. The misconcep…

Best marketing voice: "Why migrate to the sunbelt? Burn gas and wait for climate change to bring the warmth to you!"

...sigh. I really hope it doesn't go this way.

Re: “Cold Tube” cooling system uses half the energy of an air conditioner

#42

Post by samplatt »

CarbyAu wrote: post #41
eggsnbacon1 wrote: post #13

Earlier quoted context omitted.

New buildings are rather efficient in US. The problem is old buildings that use 5X the energy for HVAC. I echo that AC is quite efficient. Far more efficient than traditional heating. There's a misconception that hot areas are less environmentally friendly due to AC. The opposite is true. Hot areas are only 25 freedom units hotter than humans prefer. Cold areas have months of 50+ temperature difference. The misconcep…

Best marketing voice : "Why migrate to the sunbelt? Burn gas and wait for climate change to bring the warmth to you!" ...sigh. I really hope it doesn't go this way.

Already has, mate. There's no turning back, just a matter of damage mitigation, now.

Re: “Cold Tube” cooling system uses half the energy of an air conditioner

#44

Post by cjhveal »

mrfusion wrote: post #25
foxyv wrote: post #5

Earlier quoted context omitted.

About 60% of human body heat is lost through radiation. The cooling you would feel would be proportional to the percentage of the area around you that is covered by these cooling walls. Distance wouldn't cause that much loss because the air doesn't absorb much radiation in blackbody range of humans over distances less than 50 meters.(Infrared range with intensity peaking at 93 thousand angstroms)

But when I lose that heat through radiation it would presumably bounce around the room and not much reflects back onto my body. So I’m not seeing how much this really helps. My radiated heat shouldn’t be returning to me anyway.

Also not sure how effective this system really is, but it helped me to imagine my walls reflecting visible light as if I were in a room of mirrors and thinking about how many higher order reflections of myself would be able to reach just my pupil, multiplied by the surface area of my body.

Re: “Cold Tube” cooling system uses half the energy of an air conditioner

#45

Post by heisenzombie »

An idea I was told about relatively recently that kind of blew my mind:

- Space is cold (~3K)

- The atmosphere is really quite transparent in the wavelegth 8-13 μm

- If one can construct an optical filter (e.g. grating) which is highly reflective except for a bandpass at 8-13μm, it is possible to reflect most solar energy but still "see" the cold of deep space

- It's possible to build a box with sufficiently low thermal conduction, and this 'magic mirror' on top, to effectively refrigerate its contents by radiation to space. This uses no power, and works in direct sunlight [^1].

So weird, probably not very practical (what about cloudy days?), but very cool!

[^1] in fact, if you put it in the shade then it would warm up because it could no longer radiate to space.

Re: “Cold Tube” cooling system uses half the energy of an air conditioner

#46

Post by ladberg »

LifeIsThermal wrote: post #20

Notice how the system cools by absorbing heat from a body, but the greenhouse theory says that the earth surface warms from air absorbing heat from it. The GHE is pseudo-science.

The cooling system doesn't magically cool itself, it uses cold water to remove the heat that's added by radiation from people near it.

This has nothing to do with the greenhouse effect (which occurs when you have two bodies of drastically different temperatures with an air barrier).

Re: “Cold Tube” cooling system uses half the energy of an air conditioner

#47

Post by londons_explore »

sparker72678 wrote: post #32
dylan604 wrote: post #28

Earlier quoted context omitted.

It is amazing how tight we can make buildings today. I had to learn a lot about HVAC on a remodeling job a few years ago. I had no idea that the drywall can be sealed so tight that when the HVAC system is running it can be next to impossible to open a door without a pressure release duct. Also saw how the HVAC system had vents to bring in air from outside with baffles controlled by the system. Can't remember exact pu…

The outdoor fresh air intakes are typically via ERVs (Energy recovery ventilation systems). These systems bring in fresh air, filter it, and typically run it through a heat exchanger to minimize energy losses as the fresh air comes and and the stale air goes out. The purpose is to prevent buildup of harmful gasses and VOCs (everything from CO2 to CO to regular out-gassing of furnitures, etc) that can become dangerous…

2020: ”Poisonous stuff in our houses... Bad! Let's vent it to the environment!”

2120: The environment is all full of poisonous gasses from the people of 2020. Each house needs its own air purifier to make the outdoor air safe to breathe.

Re: “Cold Tube” cooling system uses half the energy of an air conditioner

#48

Post by userbinator »

sparker72678 wrote: post #32
dylan604 wrote: post #28

Earlier quoted context omitted.

It is amazing how tight we can make buildings today. I had to learn a lot about HVAC on a remodeling job a few years ago. I had no idea that the drywall can be sealed so tight that when the HVAC system is running it can be next to impossible to open a door without a pressure release duct. Also saw how the HVAC system had vents to bring in air from outside with baffles controlled by the system. Can't remember exact pu…

The outdoor fresh air intakes are typically via ERVs (Energy recovery ventilation systems). These systems bring in fresh air, filter it, and typically run it through a heat exchanger to minimize energy losses as the fresh air comes and and the stale air goes out. The purpose is to prevent buildup of harmful gasses and VOCs (everything from CO2 to CO to regular out-gassing of furnitures, etc) that can become dangerous…

It's been my experience that the newer high efficiency buildings seem to be optimising for that rather aggressively to the detriment of breathable air, because the air in them certainly feels a lot stuffier than in the older ones I've been in. I can certainly see building owners setting the recirculation as high as they can get away with, for the lowest cost.

Re: “Cold Tube” cooling system uses half the energy of an air conditioner

#49

Post by abrowne0 »

This is just a regular hydronic radiant system which is very efficient because it doesn’t need to heat the air. The thing is, hydronic systems have been around for 70 years or more but they typically are not used for cooling because of the humidity issues that arise which are damaging to the building. So this can only be implemented in buildings with materials resistant to water damage. Hydronic radiant systems are the best around it terms of heating efficiency but very expensive to install. This article seems like hype and bs.

Re: “Cold Tube” cooling system uses half the energy of an air conditioner

#50

Post by abrowne0 »

abrowne0 wrote: post #49

This is just a regular hydronic radiant system which is very efficient because it doesn’t need to heat the air. The thing is, hydronic systems have been around for 70 years or more but they typically are not used for cooling because of the humidity issues that arise which are damaging to the building. So this can only be implemented in buildings with materials resistant to water damage. Hydronic radiant systems are t…

It does say that there is a Novel membrane to prevent humidity build up, but there isn’t a lot of information about the membrane and what conditions it will work in. For instance, Will it work in a wooden structure with drywall?
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