'Germans Have Seen the Future, and It's a Heat Pump' - Slashdot

2022-12-05 21:30:34 By : Mr. Derek Lin

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The Fine Print: The following comments are owned by whoever posted them. We are not responsible for them in any way. Lpg Gas Geyser

Get yourself a backhoe or a drillin' rig, and a compactor, and put in your own ground loop. Pay someone to come along and do the rest of it, and go into business together. It's going to be a growth industry going forwards with increasingly chaotic weather.

Major air-water heat pump installers are asking/getting 1000 euro a man a day in labour costs here at the moment. If the water-water installers can charge that, earning back a rig won't take that long.

It's going to pig cycle, but it's still a hot market for the moment

in northern Montana it's too damn cold for them to work on the days when you need them the most

in northern Montana it's too damn cold for them to work on the days when you need them the most

You sure about that? There are pumps commercially available [templari.com] That can give you 2.4x boost even in weather as cold as -20 degree Celsius.

And with heat pumps you can harvest heat during daytime when the weather is warmer, and save it in water tanks to use during night.

in northern Montana it's too damn cold for them to work on the days when you need them the most You sure about that? There are pumps commercially available [templari.com] That can give you 2.4x boost even in weather as cold as -20 degree Celsius. And with heat pumps you can harvest heat during daytime when the weather is warmer, and save it in water tanks to use during night.

in northern Montana it's too damn cold for them to work on the days when you need them the most

in northern Montana it's too damn cold for them to work on the days when you need them the most

You sure about that? There are pumps commercially available [templari.com] That can give you 2.4x boost even in weather as cold as -20 degree Celsius.

And with heat pumps you can harvest heat during daytime when the weather is warmer, and save it in water tanks to use during night.

I'd love one, but up in Edmonton it's not uncommon to get stretches well into the -20s or even -30s, especially with the polar vortex expanding more often [ucdavis.edu]. I've heard they're improving but I think a gas furnace backup is still a good idea.

For sure, heat pumps fall into that same rhetorical trap that EVs do. Some people argue the concept doesn't work because it can't meet all people's needs everywhere all at once.

For large portions of Canada? Gas will still rule for some time, it's just too cold, life threatening cold at times. For the lower 50% of the USA though heat pumps can entirely replace gas and resistive heaters. Almost all systems will still carry resistive emergency heaters for those 1% freak occurrences.

For sure, heat pumps fall into that same rhetorical trap that EVs do. Some people argue the concept doesn't work because it can't meet all people's needs everywhere all at once. For large portions of Canada? Gas will still rule for some time, it's just too cold, life threatening cold at times. For the lower 50% of the USA though heat pumps can entirely replace gas and resistive heaters. Almost all systems will still carry resistive emergency heaters for those 1% freak occurrences.

For sure, heat pumps fall into that same rhetorical trap that EVs do. Some people argue the concept doesn't work because it can't meet all people's needs everywhere all at once.

For large portions of Canada? Gas will still rule for some time, it's just too cold, life threatening cold at times. For the lower 50% of the USA though heat pumps can entirely replace gas and resistive heaters. Almost all systems will still carry resistive emergency heaters for those 1% freak occurrences.

I have zero issues with Heat Pumps as a concept, I'd love to get one and only have my furnace kick in at -20. If nothing else I need some form of AC but I'm not sure if the cost justifies it on AC alone.

Sorry didn't mean to imply you did, speaking in generalities.

And for sure, I was gonna ask if having central AC was as common in parts of Canada. Swapping an old AC for a new one that has a heat pump makes sense. Installing AC into a house that wasn't built for it is a whole different animal. Could still make sense but is a whole different calculus

Any place with a forced air gas or oil furnace can swap in a heat pump. They will need electrical work though.

Sorry didn't mean to imply you did, speaking in generalities. And for sure, I was gonna ask if having central AC was as common in parts of Canada. Swapping an old AC for a new one that has a heat pump makes sense. Installing AC into a house that wasn't built for it is a whole different animal. Could still make sense but is a whole different calculus

Sorry didn't mean to imply you did, speaking in generalities.

And for sure, I was gonna ask if having central AC was as common in parts of Canada. Swapping an old AC for a new one that has a heat pump makes sense. Installing AC into a house that wasn't built for it is a whole different animal. Could still make sense but is a whole different calculus

Traditionally no. The houses are insulted well enough that they're usually fine in the hot weather if you keep the curtains closed. But it's changing since in the last couple years we've had a couple brutal heat waves of sustained 30+. I actually had to move to my parent's house (which has AC) since mine was so hot.

If it's hot and you don't have aircon I recommend

https://www.ezcooldown.com/[ezcooldown.com]

--they are like freezer cool packs, but melt at 59F or 70F depending on which you pick. That means they freeze in the fridge and can be worn against skin, they last an hour or so. I use them to sleep in the summer as we don't have aircon, much better than a fan. (Or use both in extreme heat).

Yeah, it'd help if we got a "geothermal heat pump boring system" that was as much cheaper to operate as SpaceX rockets are over "old space" companies.

I looked into what geothermal would cost for my house, and I was quoted $100k. I think that was a "We don't want to bother, go away" quote though.

I hate that contractors aren't willing to give me a ballpark, "Okay, I'll call you up when I have the finances for it for an exact quote" rough estimate. I don't need paperwork, but is this going to be ~$10k, $50k,

Yes, geothermal can go colder, but it still loses efficiency, and the gains are marginal.

Yes, geothermal can go colder, but it still loses efficiency, and the gains are marginal.

Depends on where you live. If outside temperature is mostly below 0, then geothermal gains are huge. You have stable temperatue of 13-14 degrees all year 'round, so you only need to gain about 20-25 degrees Celsius to prepare 35-40 degrees hot water. Besides, with geothermal you can also cool, because you're cooling your house against the 14-degrees warm ground (as opposed to: against the 35 degrees hot surrounding air).

Heat pumping efficiency is all about temperature difference between the heat reservoirs

I suspect that when the drilling costs for water get thoroughly commoditized, ground water heat pumps will start being competetive even for smaller projects. Will do AC too with FCUs.

In fact they really need to run AC, not running at net zero heat load can eventually raise the frost line.

Oops, lower the frost line.

For the lower 50% of the USA though heat pumps can entirely replace gas and resistive heaters.

For the lower 50% of the USA though heat pumps can entirely replace gas and resistive heaters.

A friend in Dallas replaced resistive heat with a heat pump. He said his calculated ROI was ~33%. No brainer!

Inflation Reduction Act has a heat pump rebate/subsidy so there is forward momentum.

We're not close politically to getting a carbon tax and a double property tax probably ends up regressive so subsidies is the most viable path.

Property taxes are local to the state with some counties getting a bit extra. There is no national property tax and trying to get one through Congress is impossible.

Clearly the market is mispricing the environmental costs ...

Clearly the market is mispricing the environmental costs ...

Clearly. I think the biggest problem is the rental market (about half of US housing) that disconnects capital investments from ongoing costs. A landlord I know dismissed that ROI with 'but I don't pay the bills' and apparently didn't think a more energy efficient rental could command higher rent. They might be correct as most renters don't check the utility costs before leasing. One idea to remedy this disconnect would be to require landlords to publish the average monthly utility costs for the past yea

Also banning resistance as the primary heating in new construction as part of the building code would be a good idea.

Also banning resistance as the primary heating in new construction as part of the building code would be a good idea.

You are quite right. But in some parts of the US (bay area), resistive heating is the only type of heating allowed in new construction. The bay area climate is too mild for heat pumps to be effective and natural gas is banned in new construction. We really need some sort of engineering or scientific council that politicians have to run ideas past before they can be passed to prevent this sort of bad policy. Just ask a contractor (ie someone who builds homes), about some of the environmental regulations

Being a pauper doesn't give you a right to kill the planet. They should be given a choice of "Lead or Silver." Subsidy to upgrade or crushing taxes if they don't.

Being a pauper doesn't give you a right to kill the planet.

They should be given a choice of "Lead or Silver." Subsidy to upgrade or crushing taxes if they don't.

That attitude is very unhelpful. It only fuels the other side as it is so extreme as to be fodder for Tucker. So kindly STFU. Also, heat pumps don't work everywhere. They probably do in Dallas but not in the bay area and confusingly work again farther north in colder places. They just need a sizeable heat differential to work, doesn't matter which way. When they have that, they are very helpful as they are so very efficient. When they don't your type of attitude tends to force electric resistive heat

They should be given a choice of "Lead or Silver." Subsidy to upgrade or crushing taxes if they don't.

They should be given a choice of "Lead or Silver." Subsidy to upgrade or crushing taxes if they don't.

Let me guess... you'll be on here later complaining about how they're living on a tent on the sidewalk after your policies have driven them out of their housing.

Even most Canadians live in places where an air heat pump works fine. BC south coast never goes below -15, and southern Ontario very rarely gets too cold. That's over half the population just in those regions.

For sure, heat pumps fall into that same rhetorical trap that EVs do. Some people argue the concept doesn't work because it can't meet all people's needs everywhere all at once. For large portions of Canada? Gas will still rule for some time, it's just too cold, life threatening cold at times. For the lower 50% of the USA though heat pumps can entirely replace gas and resistive heaters. Almost all systems will still carry resistive emergency heaters for those 1% freak occurrences.

For sure, heat pumps fall into that same rhetorical trap that EVs do. Some people argue the concept doesn't work because it can't meet all people's needs everywhere all at once.

For large portions of Canada? Gas will still rule for some time, it's just too cold, life threatening cold at times. For the lower 50% of the USA though heat pumps can entirely replace gas and resistive heaters. Almost all systems will still carry resistive emergency heaters for those 1% freak occurrences.

The number of people living in those regions is relatively low. 90% of Canada's population live within 150 miles of the US border & at least 80% of those would be well-served by heat pumps that have been available for decades. Full disclosure, in the past 50 years, I've spent roughly 20 winters in various Canadian cities, mostly Ottawa, Toronto, Montreal & Sherbrooke. A childhood friend was used to deliver heating oil in the Montreal region & when there was a huge spike in the price in the mid-200

And anyway, in the end, you do you.

But temperature statistics for Edmonton show average temperatures in winter of -15 degrees Celsius. While I accept that you can get stretches of down to -30, the question is not whether every one particular night is a total win, it's about the average. And typical air-water heat pumps can be augmented with gas or even electric "traditional" heating to get over stretches which they truly have no more capacity of withstanding.

Of course, if you can use ground heat pumps (i.e.

And anyway, in the end, you do you. But temperature statistics for Edmonton show average temperatures in winter of -15 degrees Celsius. While I accept that you can get stretches of down to -30, the question is not whether every one particular night is a total win, it's about the average.

And anyway, in the end, you do you.

But temperature statistics for Edmonton show average temperatures in winter of -15 degrees Celsius. While I accept that you can get stretches of down to -30, the question is not whether every one particular night is a total win, it's about the average.

It's only partially about the average. If the efficiency drop during stretches of -30 costs you more than savings at other times, or even worse, if the heat pump can't actually handle the temperature differential.

It still sounds doable [bchydro.com], but you still need a decent backup heat source.

And typical air-water heat pumps can be augmented with gas or even electric "traditional" heating to get over stretches which they truly have no more capacity of withstanding. Of course, if you can use ground heat pumps (i.e. wells about 100 meters deep), then you're in the green. You have around 12-14 degrees Celsius down there, so you shouldn't need anything else. Some people also use wood fireplaces even if just for the "atmosphere" of it. Doing this a dozen or so nights a winter still beats heating with gas all year round.

And typical air-water heat pumps can be augmented with gas or even electric "traditional" heating to get over stretches which they truly have no more capacity of withstanding.

Of course, if you can use ground heat pumps (i.e. wells about 100 meters deep), then you're in the green. You have around 12-14 degrees Celsius down there, so you shouldn't need anything else.

Some people also use wood fireplaces even if just for the "atmosphere" of it. Doing this a dozen or so nights a winter still beats heating with gas all year round.

Geothermal isn't really a practical solution for an existing structure. Same with a wood fireplace (also a fire risk, not to mention air pollution and some heat loss from the chimney).

I suspect gas is the most efficient augmenta

I've heard they're improving but I think a gas furnace backup is still a good idea.

I've heard they're improving but I think a gas furnace backup is still a good idea.

Hybrid heatpumps are a thing, an all in one integrated unit which will work with electricity until it doesn't and then backup the rest with gas.

I don't know who modded you up, but both them and you don't seem to understand how cold Montana gets, let alone Canada.

Across the upper Midwest US -20 C is a common overnight low in January and February. We'll get at least a week where overnight lows are -25C, and we touch -30C at least once a year. Every now and then we get slammed with colder temps than that.

And global warming isn't helping - the more hot air we push up to the north pole the more bitterly cold arctic air gets displaced and comes down to v

You sure about that? There are pumps commercially available That can give you 2.4x boost even in weather as cold as -20 degree Celsius.

In many parts of Canada, -20C is a mild day in January.

Effective functioning down to -30 would satisfy the southern third of BC, southern Ontario, and the Atlantic provinces. We're close to that point now and we're starting to see adoption in those warmer climates.

Once heat pumps function down to -45C they'll be suitable in 99% of Canada and they'll see wide-spread adoption

Once heat pumps function down to -45C they'll be suitable in 99% of Canada and they'll see wide-spread adoption.

Once heat pumps function down to -45C they'll be suitable in 99% of Canada and they'll see wide-spread adoption.

I'm not entirely sure that'll ever really be the case.

The limit is ultimately physics, not engineering. The efficiency of heat pumping is, best case, that of the Carnot cycle, and limited by the temperature difference between the cold and the hot reservoir. From -20 air to +35 water (what you need e.g. for a floor heating system ) is 55 degrees; 70 degrees if you need your water at +50 degrees (e.g. for radiator based heating system). From air at -45, on the other hand, gives 80 degrees difference, or 100 i

... in northern Montana it's too damn cold for them to work on the days when you need them the most. Just wish they could get the cost down; the last time I calculated things out I would hit payback about 15 years in,...

... in northern Montana it's too damn cold for them to work on the days when you need them the most. Just wish they could get the cost down; the last time I calculated things out I would hit payback about 15 years in,...

Sounds like it will be better / less expensive to just insulate and weatherize your home more to help the secondary (gas/electric) source on your heat pump be used less / be more effective on those (relatively fewer) extremely cold days.

I can heat my central european house on a few sticks of wood per day, ...

I can heat my central european house on a few sticks of wood per day, ...

Pro Tip: That works for your love-life too, not just your house. :-)

We are north of Montana and use normal air heat pumps to keep insulated containers above freezing in the winter to keep the larva refrigerated. They work down to about -20 C. Below that we use small supplemental heaters. Most days we can get heat of them. At nights it will often get below -20, so they shut down for a bit. We do hit -40 sometimes, but not for long periods of time usually. Average winter temperatures are not as low as we all think, despite living here!

I've always wanted to experiment with

Fun fact: In France, the green party has sabotaged for 10 years the generalization of energy saving heat pumps. Why ? Because they knew they would work on electricity which comes mostly from nuclear plants.

Now the French government is pushing for heat pumps but 10 years have been lost...

And German Greens are happy that coal power plants are up and running instead of the nuclear ones.

Seriously, the greens are just nuts...

Fun fact: These German coal plants are specifically up to prop up the French grid which has too many of its nukes down.

Fun fact: These German coal plants are specifically up to prop up the French grid which has too many of its nukes down.

No, no they aren't. Also, those coal plants in Germany use the poorest grade of coal known to man and thus cause more particulate matter and CO2 emissions per watt generated than any other fuel source of any kind. Those all those articles about France's nuclear plants being "down", yea those are bout the heat engines that make the electricity from heat, not the nuclear reactors that make the heat. German power plants have the same problems as any power plant that makes heat to make electricity has an iss

The average wait time in Germany to get a heat pump installed is more than 1 year. It is very difficult to even get someone to come out and give you an offer since most of the heating companies know that they cannot deliver anything for a long time.

Then there is the issue that most people have older houses over hear. That means standard radiators for the vast majority of houses and no underfloor heating. Most heat pumps only get the water up to 55 - 60c, which is not really hot enough unless you have underfloor heaters or very large radiators. There are a couple pumps on the market able to get to the 70 - 75c range, but they are very new, very expensive and very, very limited in their availability.

It will be at least 10 years before most houses have switched from gas/oil to heat pumps. Especially when you consider that up until about 5 years ago, the government was giving massive incentives to install new gas systems. I personally did this and have no interesting in spending another 20k, One could imagine that in 10 years the German government will change course again and fuck everyone that just spent money on a heat pump. Germany likes to pretend they know best, but from my experience, the government here is even more incompetent that most.

Abandon the hot water plumbing and switch to mini splits [carbonswitch.com].

We have those. One warms our garage to 16 degrees Celsius during winter, and the other warms my workshop to 20 degrees Celsius during winter. The Garage one works more, bigger volume to heat up, and consumed 65 KWh during the whole month of November. The other one used up under 40 KWh during the same period. Not bad.

Also, heat pumps seem to last about as long as gas fired central heating units: 10-15 years. A gas fired unit costs â1500; a heat pump will cost 10 times that.

Here in Finland, we bought our Panasonic heat pump in 2019 (pre-covid) and paid about 1000 â for it, then about 400â for installation and set-up. The pricing generally seems to be from about 800 â to 3000â (expensive heavy-duty multi-split units), and that's with our 24% VAT. Right now it's about -7C outside and our hea

Not everyone wants to give up radiant heating entirely for forced air. With a poorly insulated house, the FCU will be blowing all winter, which is a bit annoying compared to the radiators people are used to.

If you have a modern house which say only drops a single degree a day without heating in winter and where the fan unit only has to run at very low power or occasionally, air-air is a much easier option to pick. You don't give up much comfort, it's by far the cheapest option and it does AC. But most peopl

Insulation will get the needed power down, but all you really need is low temperature heating. Low temperature heating has an exponential effect, insulation just has a linear effect. To combat the linear effect of poor insulation you can linearly increase the power of the heatpump, which only sublinearly increases the cost of the install.

You don't even need to rip out all the floors for low temperature heating either if you're willing to compromise a bit on comfort. FCUs like Galletti Estro can blow 10 kW i

Germany likes to pretend they know best, but from my experience, the government here is even more incompetent that most.

Germany likes to pretend they know best, but from my experience, the government here is even more incompetent that most.

Oh, how we (the Germans) like to know best. It's a super-annoying trait, and as a scientist it is abhorring to have to endure that. And that is the issue I'm having with our government(s) (all of them since I was born): If proper scientific results on a topic are considered at all, they are cherry-picked and then presented as 'fact'.

But what is even more depressing is that there is no open-ended public discussion on any topic anyway. Every member of whichever party already knows best, and the first uttering

Then again, there are so many worse places to live, so... well. Bitching and moaning.

Then again, there are so many worse places to live, so... well. Bitching and moaning.

You sound way too reasonable to be German. Anyway, with the loss of cheap Russian gas Germany may not be such a great place to live for the next few years. Perhaps now is the time to try a different location for a few years. But then again Germany needs more reasonable people too.

the government here is even more incompetent that most.

the government here is even more incompetent that most.

The government (and politics in general) is where we stick people who are failures everywhere else. That's how the rest of the country works so well - we literally have a career path for imbeciles.

The savings are even greater for those who can run their heat pumps off solar panels

The savings are even greater for those who can run their heat pumps off solar panels

That's fun and all, but when do you need this heat pump to do most of its work? Yes, in the winter, when your solar panels are not producing enough energy to power the damn thing. This will only work when I can store the energy produced in the summer to be used in the winter.

I don't think the discussion here is about off-grid homes, those have an entirely different set of challenges.

I guess heat pump technology is considered novel in Europe? It's very common where I live (east coast, US), and it has been for years. Since it's basically just adding a reversing valve to an air conditioning unit, it's close to "free" technology. I do prefer to kick over to as heat when it gets sub-20F as it heats much faster and warmer, but the heat pump will operate at even colder temperatures.

I also have solar panels.

November 2022 I produced 78% of my electrical need.

Last December I produced 64% of my e

The savings are even greater for those who can run their heat pumps off solar panels That's fun and all, but when do you need this heat pump to do most of its work? Yes, in the winter, when your solar panels are not producing enough energy to power the damn thing. This will only work when I can store the energy produced in the summer to be used in the winter.

The savings are even greater for those who can run their heat pumps off solar panels

The savings are even greater for those who can run their heat pumps off solar panels

That's fun and all, but when do you need this heat pump to do most of its work? Yes, in the winter, when your solar panels are not producing enough energy to power the damn thing. This will only work when I can store the energy produced in the summer to be used in the winter.

That part is true. But the other part of heat pumps is cooling. And the times you want cooling tend to be peak solar production.

The story is paywalled and I can't tell from the summary or the discussion if this is somehow different from the standard temperature control devices in Japan. At least it's been a long time since I've seen any other approach... Yeah, I'm old enough to remember seeing kerosene heaters, but the standard "AC" around here for many years has been a heat pump. I even remember reading a children's book explaining how the same device pumps the heat in either direction depending on which way the valves are set.

Nope, not paywalled. Article comes right up. The problem must be on your end.

Yes, paywalled and no problem at my end except that I don't see sufficient reason to send money to the NYT versus all of the other journalists who also deserve to be supported. But congratulations to you for getting me to waste the click?

Now in solution terms, I keep thinking journalism needs some new and better financial models. Solution-oriented journalism using a #CSB is my version of that old song.

Agreed. It is good that these things got discovered, but industrialization of these ideas is far too much driven by greed and not by rationality.

There are incentives available in the UK to install a heat pump.

We loved our heatpump -- provided the bulk of our seasonal heating and cooling for 15 years. Was an air source unit -- cost us roughly $10,000 installed. Would have preferred ground source, but the rock drilling required to sink the collection wells would have added another $40,000 to the cost. The heat collection and transfer process becomes less efficient as the air gets colder -- at -10C (14F) the system shuts off. From that point we had to rely on our electric baseboards. Ground source would have been w

When I moved into a place with no AC in Montreal, I needed to install a ductless minisplit system. I really wanted a heatpump to save money heating in the winter. But the condo rules ban any water draining on the balcony. AC units only drain at the interior unit on the wall (where you can place them near a drainage line), but heatpumps drain there but also at the outdoor unit when heating. So I had to install a cooling-only unit instead of a heatpump.

If there were heatpumps that had an automatic pumped drai

Tesla switched from radiative heating to heat-pump heating for their car heaters last year. A guy tested his old vs new Model 3 and worked out it needed 2200 watts for 21C inside at 3C outside for the old Tesla, and 730 watts for the new heat-pump Tesla. Vancouver just had cold and snow that resulted in hour-long idling in traffic jams, and people were curious. It works out, with a heat pump, to 5km range lost for 80 minutes of heater.

  A bit off-topic, but it was news to me, today, that a heat pump can be a little thing, under a car hood, not necessarily a box the size of a large suitcase.

https://electrek.co/2020/12/03... [electrek.co]

A heat pump is basically just an air conditioning unit running in reverse. An AC pumps heat from inside your house to the outside in summer (and the exhaust air from the outside unit blows off hot air). In winter the flow is reversed, and heat from the cold air outside is pumped inside (and the exhaust air from the outside unit is even colder). There's barely any additional equipment needed beyond what a car already has for an AC.

I think the only downside is that a heat pump needs to be sized larger in order to be able to effectively heat.

Our nissan leaf '16 has heat pump and it's the fastest-heating car we've ever owned. The interior is warm much faster than with an direct-mains additional heater (800-1600W, car models) or my volvo with a gas-fueled eber heater (though that one is not direct internal air but for the engine). This is in temperatures of 5c to -10C. Unfortunately the battery on the leaf is only 30kWh so the range drops off steeply below -10c, though still enough for the town rides.

That's a much brighter "Vision of the future" than the one they had in the 30's

Where can I get it that fast? I just got an offer and the delivery time is a year.

A heat pump provides more thermal energy

A heat pump provides more thermal energy

To be precise, it moves it. From outside to inside.

Of course you realize that extracting energy from the outside environment could reduce or even wipe out all the global warming gains that we've been striving to produce*.

*That's how you trigger the morons.

Of course you realize that extracting energy from the outside environment could reduce or even wipe out all the global warming gains that we've been striving to produce*. *That's how you trigger the morons.

Of course you realize that extracting energy from the outside environment could reduce or even wipe out all the global warming gains that we've been striving to produce*.

*That's how you trigger the morons.

I think you are just being silly here. Heat pumps can move heat in both directions and are used to also cool (Air Conditioners) but that's beside the point all the heat moved inside/outside will eventually reach an equilibrium so will do nothing to help global warming.

A heat pump provides more thermal energy to heat a room than what is supplied to operate it. Therefore it is more than 100% efficient.

A heat pump provides more thermal energy to heat a room than what is supplied to operate it. Therefore it is more than 100% efficient.

A heat pump by itself is not a closed system, thus the First Law of Thermodynamics does not apply.

The exhaust of the heat pump is colder than the environment where the heat is taken from. The electrical energy supplied is used to move the heat energy from one point to another, as this won't happen by itself, as the Second Law of Thermodynamics tells us.

Considering you don't provide any thermal energy to operate a heat pump, that's not really very impressive.

Hahahaha, no. Thermodynamics is intact. But a heat pump does not ignore the outside air and ground temperatures and uses them.

All refrigerant based systems are capable of over 100% efficiency because they are not "creating" heat energy, they are just moving it from one location to another.

Yes, a resistive heater or gas furnace can never go over 100% due to conservation of energy laws but those are doing an entirely different type of operation.

Yeah, as you know Finland's balmy climate is similar to the south of France. There's just no comparison between the frigid wastes of Germany and the sunny beachside towns of Lapland, so those heat pumps will have no chance of taking off in Germany like they have done in Finland.

Actually, 15k is a joke compared to what a house costs here in Germany. A standard one-family stand-alone house in the suburbs of Munich will currently cost you about 1.5 - 2 million Euros (which is, currently, about the same in USD). I have no clue whether we are even allowed to drill here (probably not), but that is not a prohibitive cost. Right now, we are all trying to get solar power installed on our roofs, partly because of cost, and partly because the government doesn't get to dictate how we use it.

Ah, yes. The US folks would think these are ElCheapo cardboard US houses. They are not.

No drilling needed in Germany. Just digging down for a bit. This stuff does work and there are by now enough reference installations in Germany.

Air source heat pumps are *less* efficient than burning gas or oil below some outside temperature that a northern country like Germany will experience pften enough.

Air source heat pumps are *less* efficient than burning gas or oil below some outside temperature that a northern country like Germany will experience pften enough.

With modern heat pumps, that's going to be very rare in Gemany. First regarding the efficiency of heat pumps [wikipedia.org],

The heat pump's performance is limited by the Carnot cycle and will approach 1.0 as the outdoor-to-indoor temperature difference increases, which for most air source heat pumps happens as outdoor temperatures approach -18 C (0 F). Heat pump construction that enables carbon dioxide as a refrigerant may have a COP of greater than 2 even down to -20 C, pushing the break-even figure downward to -30 C (-22 F).

The heat pump's performance is limited by the Carnot cycle and will approach 1.0 as the outdoor-to-indoor temperature difference increases, which for most air source heat pumps happens as outdoor temperatures approach -18 C (0 F). Heat pump construction that enables carbon dioxide as a refrigerant may have a COP of greater than 2 even down to -20 C, pushing the break-even figure downward to -30 C (-22 F).

So they remain more efficient than conventional heating down to -18 C for most heat pumps, and down to -30 C for the better ones. Now regarding the climate in Germany [climatestotravel.com],

In winter, the average temperatures are around 2/3 C (35/37 F) in the west and the north, while they are around 0 C (32 F) in the east and in Bavaria.... During cold waves from Siberia (which, however, are becoming rarer due to global warming), temperatures can plunge to -15/-20 C (-4/5 F) in much of Germany, but these periods usually last for a few days in the north and central part, while they tend to last longer in Bavaria, where cold air stagnates with more ease.

In winter, the average temperatures are around 2/3 C (35/37 F) in the west and the north, while they are around 0 C (32 F) in the east and in Bavaria.... During cold waves from Siberia (which, however, are becoming rarer due to global warming), temperatures can plunge to -15/-20 C (-4/5 F) in much of Germany, but these periods usually last for a few days in the north and central part, while they tend to last longer in Bavaria, where cold air stagnates with more ease.

So most of the time in winter the temperature is far above the break even point for all heat pumps. During rare cold waves it can fall to about the break even point of most heat pumps, but still well above the break even point of the

That "some temperature" [below which a heat pump is less efficient than burning the fuel directly] is less than about -20C which is colder than it gets in Germany almost ever.

(-4F for those in the US who don't want to do the conversion. I lived in lower Michigan, where a sustained cold snap with -4 lows was a once-in-several-years event.)

What I'd like to see is a combined machine incuding this assambly: - Natural gas engine with an Atkinson or HEHC cycle (the latter is 30% more efficient than diesel

Forgot to mention that the moisture in the exhaust gas would be condensed for still more heat scavenging - the "condensing mode boiler" arrangement that is now required in new fuel-based boilers across Europe.

Mostly because air conditioning is not nearly as common in many European countries.

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