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I heat my home by mining crypto currencies

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Re: I heat my home by mining crypto currencies

#241

Post by lmilcin »

twobitshifter wrote: post #123
lmilcin wrote: post #100

Earlier quoted context omitted.

No, heat pumps don't have over 100% efficiency the same way hot water pumps that pump from municipal source don't have >100% efficiency in heating home (it uses hot water available from somewhere else). Heat pumps engage some other source of energy so if you want to measure efficiency you now need to include that other source into account. Since you are engaging natural source of energy you can measure how effective…

The efficiency calculation here measures only electrical power in vs heat energy out. Heat pumps are always listed with greater than 100% efficiency. There is no problem with the laws of thermodynamics of doing this and it’s even listed in text books with the explanation of how it is possible. The work of the heat pump is to move heat from one location to another, it does so with the byproduct of producing more heat,…

I guess you are mistaken about what a heat pump is.

Heat pump is a closed system in which you store energy when it is hot and recover it when it is cold.

https://en.wikipedia.org/wiki/Heat_pump

Heat pump is not just the pump mechanism, but the entire system which includes mass of rock that is heat reservoir.

What typically happens is you drill deep in the ground or rock and circulate air, water or some other refrigerant underground. During summer you pump hot refrigerant to heat up the mass of rock. This can be for example water that has been made hot by the sun. During winter you push water through that warm rock to recover the heat to warm your home.

No, it is not thermodynamically possible to recover more than 100% of stored energy.

Re: I heat my home by mining crypto currencies

#242

Post by user-the-name »

lmilcin wrote: post #225
user-the-name wrote: post #131

Earlier quoted context omitted.

I think you are thinking of something very different than what "heat pumps" actually are? They don't involve storing heat, they're just an inverse fridge.

I think guys you are all wrong. https://en.wikipedia.org/wiki/Heat_pump The first sentence: "A heat pump is a device that transfers heat energy from a source of heat to what is called a thermal reservoir ." So yes, it involves energy storage. The way this works is you store heat in the summer (warm up a lot of rock or ground underneath your house) and recover that energy in the winter by pumping a liquid through warm…

Given that the neighbouring house has one on their wall, I think I know what they are.

Re: I heat my home by mining crypto currencies

#243

Post by dudul »

bluGill wrote: post #234
dudul wrote: post #153

Earlier quoted context omitted.

What a few of these "lot of cases" where they are not viable?

Anytime it is "cold" air source heat pumps don't work. Cold varies a bit, somewhere between -5C and - 25C depending on design factors. Even in the best case as you get closer and closer to the minimum temperature the worse they work (IE when you need them most!), and once you hit the cut-off you better have a backup source off heat. You can use geothermo (ground) to work around this. I'd recommend it, but the one tim…

OK, so that's one, very well understood case. Yes, a heat pump will not work all the time. I have one and it stops working around 20F and the furnace takes over. So what? I live at the US/Canada border and my furnace runs maybe ~2 months during the year. This is still tremendous savings.

Re: I heat my home by mining crypto currencies

#244

Post by TomSwirly »

hutzlibu wrote: post #171
nr2x wrote: post #157

Earlier quoted context omitted.

The questions are twofold: does Facebook do more good than bad? Could the good be accomplished without much of the bad? The answers to both questions are arguably bad for Facebook.

But then why is there no serious competitor?

A social network is a natural monopoly. You are kept at Facebook because all your friends are on Facebook, and they are kept there because you are.

Re: I heat my home by mining crypto currencies

#245

Post by liminvorous »

lmilcin wrote: post #225
user-the-name wrote: post #131

Earlier quoted context omitted.

I think you are thinking of something very different than what "heat pumps" actually are? They don't involve storing heat, they're just an inverse fridge.

I think guys you are all wrong. https://en.wikipedia.org/wiki/Heat_pump The first sentence: "A heat pump is a device that transfers heat energy from a source of heat to what is called a thermal reservoir ." So yes, it involves energy storage. The way this works is you store heat in the summer (warm up a lot of rock or ground underneath your house) and recover that energy in the winter by pumping a liquid through warm…

I think wikipedia is wrong or confusing here. A heat pump requires a thermal resevoir (something that doesn't change temperature much when you move heat to or from it) of some sort, usually the atmosphere, or in ground source heat pumps pipes running through the ground, but it can move heat in either direction.

> While air conditioners and freezers are familiar examples of heat pumps, the term "heat pump" is more general and applies to many heating, ventilating, and air conditioning (HVAC) devices used for space heating or space cooling.

Basically what I would understand from the term heat pump in ordinary conversation would be an air conditioner intended for use in a heating dominated climate rather than a cooling dominated one, but there might be some regional differences in usage.

Re: I heat my home by mining crypto currencies

#246

Post by rl3 »

bryanrasmussen wrote: post #141
cinntaile wrote: post #120

Earlier quoted context omitted.

You have been here for a couple of years, surely you have noticed downvotes don't always make sense.

sure, but I suppose it makes sense to the person making the downvote. And when it makes especially poor sense to me I start to think - maybe they see something I don't? on edit: I do sometimes also get paranoid and think, man there is just someone who doesn't like me and automatically downvote when they run across my name!

>I do sometimes also get paranoid and think, man there is just someone who doesn't like me and automatically downvote when they run across my name!

It certainly can feel like that sometimes. I rarely enjoy posting here anymore as a result. The fact a single downvote can inhibit your comment's visibility and negatively bias its progression is silly.

The unsettling part is it feels like there's very little stopping individuals and organizations from weaponizing that dynamic. Anything from targeted sustained psychological distress to censorship is possible with the current scheme.

Re: I heat my home by mining crypto currencies

#247

Post by Haemm0r »

pedrocr wrote: post #236
Haemm0r wrote: post #219

Earlier quoted context omitted.

If you do not have temps below 0-5°C that might be true. Below the freezing point efficiency drops quite a bit.

"Name a source please" :) Keeping 5x over the entire winter includes some pretty cold nights. And ground source systems can improve even this by quite a bit.

Nicely played :)

Here we go: https://industrialheatpumps.nl/en/how_it_works/cop_heat_pump...

or better this pic: https://www.researchgate.net/figure/Performance-map-of-the-h...

Re: I heat my home by mining crypto currencies

#248

Post by twobitshifter »

lmilcin wrote: post #241
twobitshifter wrote: post #123

Earlier quoted context omitted.

The efficiency calculation here measures only electrical power in vs heat energy out. Heat pumps are always listed with greater than 100% efficiency. There is no problem with the laws of thermodynamics of doing this and it’s even listed in text books with the explanation of how it is possible. The work of the heat pump is to move heat from one location to another, it does so with the byproduct of producing more heat,…

I guess you are mistaken about what a heat pump is. Heat pump is a closed system in which you store energy when it is hot and recover it when it is cold. https://en.wikipedia.org/wiki/Heat_pump Heat pump is not just the pump mechanism, but the entire system which includes mass of rock that is heat reservoir. What typically happens is you drill deep in the ground or rock and circulate air, water or some other refriger…

We’re talking of home heating where the ground source heat pumps are rare. Here’s an article explaining how they work. Efficiency is 200-300%

https://www.finehomebuilding.com/2020/04/08/how-efficient-ar...

Re: I heat my home by mining crypto currencies

#249

Post by bluGill »

dudul wrote: post #243
bluGill wrote: post #234

Earlier quoted context omitted.

Anytime it is "cold" air source heat pumps don't work. Cold varies a bit, somewhere between -5C and - 25C depending on design factors. Even in the best case as you get closer and closer to the minimum temperature the worse they work (IE when you need them most!), and once you hit the cut-off you better have a backup source off heat. You can use geothermo (ground) to work around this. I'd recommend it, but the one tim…

OK, so that's one, very well understood case. Yes, a heat pump will not work all the time. I have one and it stops working around 20F and the furnace takes over. So what? I live at the US/Canada border and my furnace runs maybe ~2 months during the year. This is still tremendous savings.

Big savings, but is it big enough to be worth the extra expense of a heat pump vs used using the furnace year round. The times when the heat pump works are the times when you least need it, since other activities of life are adding heat to the house too.

Re: I heat my home by mining crypto currencies

#250

Post by oefrha »

lmilcin wrote: post #225
user-the-name wrote: post #131

Earlier quoted context omitted.

I think you are thinking of something very different than what "heat pumps" actually are? They don't involve storing heat, they're just an inverse fridge.

I think guys you are all wrong. https://en.wikipedia.org/wiki/Heat_pump The first sentence: "A heat pump is a device that transfers heat energy from a source of heat to what is called a thermal reservoir ." So yes, it involves energy storage. The way this works is you store heat in the summer (warm up a lot of rock or ground underneath your house) and recover that energy in the winter by pumping a liquid through warm…

Thermal reservoir is a technical term in thermodynamics and as others have pointed out it doesn’t mean what you think it means. Anything remotely resembling a (reversed) Carnot cycle would involve thermal reservoirs. You can read its own Wikipedia page.
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