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Climate change

Most of us live in places where the average daily temperature is still clearly above 0°C at almost all days of the year. Therefore the challenge of keeping air/water heat pumps within reasonable operating range is mainly a question of energy management and storage.

In many cases it is just the water in your system together with the insulation of the house (indoor temperature in most houses doesn’t change too much if the heating is off for some hours) but for larger buildings or energy demand there are also technologies like water/Ice storage that are extremely effective to buffer for the times of the day, where a air/water heat pump can not be operated effectively.

Germany

Most of us live in places where the average daily temperature is still clearly above 0°C at almost all days of the year.

That is the case in the UK too, statistically, but if your house falls to +10 when the outside is say -5 then you are going to be very unhappy.

Even if the COP falls to 1 at low temps, it still won’t work because your house now actually needs the whole 20kW

One can improve the COP first by trying to avoid evaporator icing but that needs a much larger evaporator (so the negative delta T is reduced) which makes the heat pump even bigger than they are now, and offers only limited protection; it will still freeze up.

Administrator
Shoreham EGKA, United Kingdom

I thought the bigger problem in new office blocks was cooling as each person produces a certain amount of heat per hour. In order to counter this many office buildings in the 90’s had ice storage on the roof which transferred cooling air to ducting rather than conventional air conditioning systems. I never heard of ice being used to store heat though. How does it work?

France

gallois wrote:

I never heard of ice being used to store heat though. How does it work?

Technically you obviously do not use the ice but the heat that is released during process of icing:

You basically have a large tank of (Salt-)water where you install a water/water heat pump – basically like what you would do if you had access to a stream of water. As a limited storage of water has only limited heat capacity, the “trick” is, that the freezing of the water happens by design and the huge amount of energy that is released during freezing is leveraged for heat generation.
The ice is then melted again partly by using the surrounding heat when OAT is higher, partly by active heating that is done in times where OAT is clearly above freezing levels. So most advanced ice storage systems have actually two heat pumps attached: One water/water heat pump to heat the building and freeze the storage and one air/water heat pump to melt the ice in the tank.

That is a very good match for the typical building heat requirements in Europe, where during daytime on almost all days OATs are quite good for effective use of Air/air heat pumps while at night they can be outside effective operating range.
It is also pretty effective and efficient in terms of total COP, but only if build at larger scale. Therefore it is typically not a solution for individual homes – esp. not if they are insulated up to current standards – but rather for larger buildings or entire blocks.

Germany

A heat pump using a stream would have a problem if many were in use – eventually freezing the stream.
Wind speeds should affect the building heat loss.

Maoraigh
EGPE, United Kingdom

I did a quick and dirty calc with say a 1m3/sec flow rate (a reasonable size stream) and working with a 5K delta T (so the water stays liquid so long as it was above +5C), I reckon it comes to about 20MW.

That’s enough to heat about 1000 typical 5-bedroom houses.

Administrator
Shoreham EGKA, United Kingdom

I generally try to avoid political threads such as this one since I know that my views are not shared by a lot of people, or will even be regarded as radical by others. Just ask my wife
Nevertheless, whilst sorting out my digital albums, I came upon zillion of pictures taken whilst crisscrossing my playground, namely the Alps.

The 2 pictures shown here depict the same glacier, namely the Rohnegletscher, aka Rottengletscher, aka Rhône Glacier. Above it sits the 3630m summet of the Dammastock. The river Rhône has its source here, feeds Lake Leman aka Lake Geneva, and crosses Southern France before fading into the Mediterranean South of Arles. On the right of the Glacier, the road leading towards the Furkapass is nicely visible. The Belvédère hotel, and the tourist attraction Ice Grotto parking lot are also to be seen.
One picture has been taken on the 16th of July 2007, whilst the other one was taken on the 4th of October 2021, slightly more than 14 years in between them.
So, the ice is melting… the planet is warming up… we burned, and are still burning incredible amounts of fossil fuel… at the same time we are accelerating deforestation… whilst the human race is procreating at a higher pace…


Dan
ain't the Destination, but the Journey
LSZF, Switzerland

Dan wrote:

I know that my views are not shared by a lot of people, or will even be regarded as radical by others. Just ask my wife

Ditto……Thank you for sharing the photographs. They do indeed tell a story and a visualisation of the retreating glacier. I think the major problem that we as a species face is that there are so many narratives being given that it is extremely difficult to understand what the problem is, is there a problem and if there is a problem, how and can we tackle it.

How can we, mere humans, alter the natural structure and evolution of our planet? The answer is we cannot. We can talk the talk but we cannot at this moment change anything.

1. GLOBAL TOPSOIL LOSS & DEGREDATION – is actually our biggest issue.
2. GLOBAL FARMING STRATEGIES – See 1
3. DEFORESTATION – See 1& 2.

In my view the average politician has not one clue about any of the above, therefore if they use giant sexy agendas like Climate Chatastrophe, Melting Glaciers and rising sea water, Climate Extinction, makes them all sound a bit better. It is an incredibly complicated scenario, dumbed down by the politicos for mass fodder and fear.

Fly safe. I want this thing to land l...
EGPF Glasgow

I think most people including politicians now accept that the climate is changing.
Whether they believe it is man made and can therefore be halted is another matter.
Politicians understand that there is a problem but are too afraid to put the measures to stop it in action for fear of losing votes and their power.

France

gallois wrote:

I think most people including politicians now accept that the climate is changing.

The climate has always been changing. But that always seem to be “forgotten” or played way down. Below is the graph of the average temperature on Svalbard since the ice age ended. Yes, we had an ice age ending only a few thousand years ago with ice covering most of the northern hemisphere. The glaciers all over the worlds has retreated ever since. The dwindling of glaciers we see today, is mostly due to global warming that started 12-15 thousand years ago. Well, except on a few extreme locations, as for instance Svalbard.

During the ice age it was very cold there, completely frozen, 13k+ years ago. Then, when the ice age ended, it got very warm, 6 deg warmer than today 9-10k years ago. Then it slowly cooled down over the millennia. It started rising again about 3000 years ago, and had a peak about 1000 years ago followed by a sharp dip. Today it is rising again, but that started already 500 years ago, long before any man made climate change.

The reasons for this is not unknown. It is mainly 3 factors, but combined with lots of other factors:

  1. The earth axis of rotation is wobbling. With a period of 40k years, the polar circle is wandering from 65 deg 30 second to 67 deg 54 second, or about 24 meters per year.
  2. The earth orbit around the sun is oval.
  3. the freezing and thawing of the north pole in a complex pattern caused by ocean currents (the Golf stream mainly) and 1 and 2 above.

What happens is that the combination of axis wobbling and the earth oval axis, sometimes make the summers at one pole much warmer. The wobbling is at it’s max at the same time the earth is closest to the sun in the summer. This will thaw the sea at the north pole. Conversely when the wobbling is at it’s minimum at the same time as the earth is farthest from the sun in the summer, will cool the polar sea. The south pole is different. There is no sea there, it’s an entire continent of solid ground, thus it stay frozen. Lots of ice ages during the last millions of years, and they all fit this as clockwork, more or less. The difficulty is the unpredictable sea currents and other stuff happening, such as volcanoes and meteorites.

Today we also have more CO2 in the atmosphere. However, blaming this for the thawing of glaciers is as dumb as blaming a rainy day for the tidal water. What wee see is a raise in the CO2 level. Tons and tons and tons of talk about how this increases the global temperature. Then we see glaciers melting and immediately jump to the wrong conclusion The glaciers would have melted even if there were no humans on the planet, and they will start to grow several thousand years in the future.

How often do anyone hear read about the wobbling of the earth axis, the oval orbit of the earth, and the ocean currents at the north pole as a perfectly well known cause of periodic ice ages during the last millions of years? I bet not a single time. Yet, this is well knows to all so called “climate scientists”. It’s just that it’s not very interesting talking about this at “climate summits”, because it will hurt the case and diminish humans to the insignificant apes we really are

The climate is 99% religion today. And as religious leaders gathered to try to understand and affect the gods to prevent certain Ragnarok, so do politicians today.

The elephant is the circulation
ENVA ENOP ENMO, Norway
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