Won't heat pumps make everything else colder?

[Gralick]

I was reading this article about heat being extracted from rivers to warm houses. Where I live, people and businesses are installing ground heat exchangers. I've also seen a lot of new housing that uses air heat pumps.

Now, I'm no engineer but isn't this just another way of extracting a natural resource and fucking up the environment? Won't rivers get colder as this method of heating takes off? Since heat from water helps moderate air temperatures, that would make the climate colder. If average water temperatures drop, won't that alter the habitat for all the things that live in it?

Same argument for ground pumps. I'm not sure about air exchangers. AIBU to think this will eventually leave me freezing my arse off in my gas-heated flat, while the UK climate goes all Scandinavian? Come and talk physics to me!

As the oceans are warming up, the tiny tiny amount if heat we can extract from them will only do good, if it has any affect at all. Same goes for rivers unless the heat exchange is quite far upstream and excessive.

Yes half right, They don't affect that big an area. Like heat pumps,make the ground colder in your garden but not the whole street, it can affect things like when your bulbs flower but not whole climate (sea and sun are much bigger forces).

Oh, that's interesting - and reassuring, ragged :)

Dragons, global warming makes more ice melt off the Arctic and flow down towards us - a couple of times the Gulf Stream nearly didn't happen because of this. It's going to make Britain colder. Damn it! I want to be warm!

You absolute numpties. First law of thermodynamics. Heat pumps just move heat from one area to another. Then add a bit of heat for good measure because of inefficiency.

I think I'm the only numpty The two PPs seem to have more of a clue!

If you're moving heat from inside a river to inside a house, it's going to make the house warmer & the river colder, surely? According to the Numpty Law Of Thermodynamics.

Otherwise, why bother moving it??

I was reading a blog by an amazing engineer who had a ground source heat pump, it was the borehole type, rather than the kind which is spread out over a large area. She had rigged up solar panels to reheat the earth around it, when the efficiency had dropped over a few years. She was basically using her garden as a big battery; a big rechargeable battery.

Yes, it makes the river colder. Then, your house cools down (i.e. heat escapes to the rest of the world) and all is right with the earth.

You're right, ram, I am a numpty! Yes, "house gets colder" = "heat goes back outside".

That's genius, Boofy. I've spent many lost hours dreaming up similar schemes. Since I now live in a flat with no outdoor space, I'll have to stay gas-dependent, but it's nice to hear they work!

Well, OK, they work for an engineer and I'm a numpty. But you know.

Since I now live in a flat with no outdoor space, I'll have to stay gas-dependent, but it's nice to hear they work!

What about beer cans, black paint, perspex and a wooden frame?

Since I now live in a flat with no outdoor space, I'll have to stay gas-dependent, but it's nice to hear they work!

I've wondered whether I could install an air-conditioning unit to heat my flat. I think there are some that claim they can generate five times as much heat as the electricity they consume could generate directly. Even if they fall a little short of their target, that would make energy costs comparable with gas. I have a modern flat, but it has an integral garage that is not really thermally separate from outdoors, so I wonder if the outdoor component could go in there.

I reckon gas is a lot more expensive than people realise, once you add in the cost of boiler maintenance and replacement, and that if air-source heat pumps were built into modern flats, they'd probably have equal or lower running costs. Not sure how much of a problem their noise would be.

It looks like it has been tried, off to read this...

www.gov.uk/government/publications/examination-of-performance-of-air-source-heat-pumps-in-a-london-social-housing-block

Hmm - interesting ideas! The management would definitely not approve of a DIY solar battery on the outside wall, though

The second law of thermodynamics says that heat pumps cannot operate at 100% efficiency. Wasted energy becomes heat. They will actually make more heat, and make things slightly warmer. You can't transfer heat (or any form of energy, for that matter) from one place to another without losing some of it.

If you like this sort of thing, have a look at wood gasification boilers.

Of course, climate is a funny thing. If global warming were to shut down the thermohaline circulation of the North Atlantic, which is something some researchers think is possible, then the UK might well get a more Scandinavian-like climate as a result of global warming. I'm not a climatologist, I don't know how likely anyone considers this to be.

We've had some really cold winters in the northeastern US the past couple of years. That doesn't mean global warming is not happening. Global warming doesn't necessarily mean there will be a uniform increase in temperature everywhere. It's more complicated than that.

The second law of thermodynamics says that heat pumps cannot operate at 100% efficiency. Wasted energy becomes heat.

From a random web site I googled

The electric heat pump can overcome the thermal bottleneck imposed by the second law of thermodynamics for the purpose of heating a house. As the illustration shows, an electric heat pump can deliver more heat to a house than burning the primary fuel at 100% efficiency inside the house.