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Not heat pumps? No idea what you're talking about. Evaporative cooling, passive cooling, cooling by ventilation, plants. You mean these? Well at least these AC

by ephbit 4y ago

Not heat pumps? No idea what you're talking about. Evaporative cooling, passive cooling, cooling by ventilation, plants. You mean these? Well at least these AC units in cars and the humming things mounted in millions to outside walls of buldings are all heat pumps. Don't know what other AC you mean then. As to thermodynamics, apart from using the term, would you care to explain how it supposedly explains your claim? Maybe you arbitrarily set the earth's system boundary to the outside walls of all AC'ed spaces?

gumby 4y ago
A “heat pump” is a specific kind of device that can function either as a heating or cooling device depending on its mode, basically transferring heat from one side to the other. An “air conditioner”, as traditionally defined, is basically a refrigerator: it compresses a gas and then lets it expand through a valve; it becomes cold due to Boyle’s law (I suppose you could make one like a gas powered fridge instead of using an electric pump but I’ve never seen one). You can use that to generate cooler ambient air and then radiate it outside the way a fridge does. And in either case the thermodynamics situation is simply the second law: it takes energy to do all that work, which turns into heat. Sure, the energy from a fossil fuel was originally solar power, but that was millions of years ago. You can’t just magically claim its part of the current energy balance. The significant contribution of air conditioning to heat islands has been widely discussed for decades.
- ephbit 4y ago
  Yeah sure, in the practical sense different terms are established for the different applications, but that doesn't change the fact that what you call a "heat pump" works by the same principle as what you call an "air conditioner". I was more refering to the general thermodynamic principle of a heat pump and it appears that others too use the term in that general sense. Citing from Heat Pumps in Chemical Process Industry (by Kiss, Infante Ferreira) [1] > Notably, the term heat pump is more generic; it applies to many heating, ventilating and air conditioning (HVAC) devices used for space heating or cooling. When used for heating, a heat pump employs the same refrigeration-type cycle ... "When used for heating" clearly indicates that the term is valid for both types of applications. > And in either case the thermodynamics situation is simply the second law: it takes energy to do all that work, which turns into heat. You better read up on what the second law means. What you write "takes energy .. which turns into heat" is actually linked to the first law. > Sure, the energy from a fossil fuel was originally solar power, but that was millions of years ago. You can’t just magically claim its part of the current energy balance. I am not making that case. The claim I am making, is that it doesn't matter for what kind of purpose you use this fossil energy (except for the weird uses I mentioned) because _all_ purposes will eventually turn it into heat. Which is why I reject the claim that "AC heats up the planet". No, fossil energy use does, no matter what you use it for. > The significant contribution of air conditioning to heat islands has been widely discussed for decades. Your original claim was "AC heats up the planet though". Now you write "heat islands". Yeah, of course you have heat islands. I don't deny that. It's just something totally different from "heating up the planet". Because transferring heat from inside building to the surroundings doesn't change the planet's _thermal_ energy balance. It's the burning of fossil fuels that does so. [1] https://www.google.com/books/edition/Heat_Pumps_in_Chemical_Process_Industry/zx8NDgAAQBAJ?hl=en&gbpv=1&printsec=frontcover&bsq=heat%20pump%20generic https://www.google.com/books/edition/Heat_Pumps_in_Chemical_...

by ephbit 4y ago

gumby 4y ago

A “heat pump” is a specific kind of device that can function either as a heating or cooling device depending on its mode, basically transferring heat from one side to the other. An “air conditioner”, as traditionally defined, is basically a refrigerator: it compresses a gas and then lets it expand through a valve; it becomes cold due to Boyle’s law (I suppose you could make one like a gas powered fridge instead of using an electric pump but I’ve never seen one). You can use that to generate cooler ambient air and then radiate it outside the way a fridge does. And in either case the thermodynamics situation is simply the second law: it takes energy to do all that work, which turns into heat. Sure, the energy from a fossil fuel was originally solar power, but that was millions of years ago. You can’t just magically claim its part of the current energy balance. The significant contribution of air conditioning to heat islands has been widely discussed for decades.

ephbit 4y ago
Yeah sure, in the practical sense different terms are established for the different applications, but that doesn't change the fact that what you call a "heat pump" works by the same principle as what you call an "air conditioner". I was more refering to the general thermodynamic principle of a heat pump and it appears that others too use the term in that general sense. Citing from Heat Pumps in Chemical Process Industry (by Kiss, Infante Ferreira) [1] > Notably, the term heat pump is more generic; it applies to many heating, ventilating and air conditioning (HVAC) devices used for space heating or cooling. When used for heating, a heat pump employs the same refrigeration-type cycle ... "When used for heating" clearly indicates that the term is valid for both types of applications. > And in either case the thermodynamics situation is simply the second law: it takes energy to do all that work, which turns into heat. You better read up on what the second law means. What you write "takes energy .. which turns into heat" is actually linked to the first law. > Sure, the energy from a fossil fuel was originally solar power, but that was millions of years ago. You can’t just magically claim its part of the current energy balance. I am not making that case. The claim I am making, is that it doesn't matter for what kind of purpose you use this fossil energy (except for the weird uses I mentioned) because _all_ purposes will eventually turn it into heat. Which is why I reject the claim that "AC heats up the planet". No, fossil energy use does, no matter what you use it for. > The significant contribution of air conditioning to heat islands has been widely discussed for decades. Your original claim was "AC heats up the planet though". Now you write "heat islands". Yeah, of course you have heat islands. I don't deny that. It's just something totally different from "heating up the planet". Because transferring heat from inside building to the surroundings doesn't change the planet's _thermal_ energy balance. It's the burning of fossil fuels that does so. [1] https://www.google.com/books/edition/Heat_Pumps_in_Chemical_Process_Industry/zx8NDgAAQBAJ?hl=en&gbpv=1&printsec=frontcover&bsq=heat%20pump%20generic https://www.google.com/books/edition/Heat_Pumps_in_Chemical_...