Geothermal installation on water table in 2013?

[chatelot16]

danielj did not understand everything

any heat pump has a cop which varies depending on the difference between hot and cold temperature

with a well if the flow is sufficient we always have the same cold temperature: it is much better than an air heat pump, which has a cold temperature too cold when it is cold, which decreases the COP on days or we need it the most

where does this 7 ° temperature drop in the exchanger come from? when the well gives a sufficient flow we can have a lower temperature loss

the air heat pump also has a temperature drop in the air sensor, and even stronger than the water water heat pump

I find it a pity that the water water heat pump is so expensive

how deep is the well? it is when the drilling is deep that the flow is reduced so as not to spend too much power on pumping but when the depth is reasonable you should not hesitate to put a large flow

[raymon]

At the moment my air / air conditioning consumes 5 kWh per day to heat 45m2 of average insulation by operating from 7 am to 23 pm but every evening I light my wood stove. At night the temperatures are negative and my house is exposed north west.
The air / air conditioning with a good cop is a very profitable investment when you have another means of heating by negative temperature.
I live on the 2nd floor and going up the wood every day is not easy but an armful in the evening is fine.
Probably water / water clims are expensive because not widespread (economy of scale) and not everyone has a shallow well with good flow.

[Forhorse]

I don't see why an air / water heat pump would only last 10 years and a water / water heat pump would last 20 years.
The principle and the components are the same.
And anyway in 8 years, when the first breakdown occurs, the speech of the "convenience store" will be the same: "it's too old, the parts are no longer made, everything must be changed ..."

[danielj]

A water-water cap, or air-water can only operate with a cop (performance coefficient) greater than 1 if the temperature of the hot source is greater than 7 ° C (approximately) due to the freezing of the exchangers. with a temperature of 7 ° C from the hot spring, the exchanger will have to cool to zero degrees Celsius to extract calories, so it will frost the exchanger, logical, whether it is water or air! this results in a blockage of the exchanger. In this case, the heat pumps are equipped with a defrosting system. Two types of defrost: - with a resistance which heats the external exchanger, or by reversing the circulation of fluids, which consists in taking calories inside, to cool the exchanger from outside (!). The user, normally when everything is nickel, does not notice anything, it continues to heat up! For the good reason that powerful resistances hidden in your cap, come to compensate for the insufficiency of the thermodynamic system. But then the output of the cap is no better than a simple electric convector heater, yet 100 times (a thousand times) cheaper! !
If the temperature drops to around 7 ° C, the electrical resistances. heat water (or air). An air-to-air cap is economical only in mid-season, when the outside temperature is around 15 ° C, and the inside temperature around 21 ° C. There the cop can be from 2 to 4. Often the maximum cop are given for an outside temperature equal to the inside temperature of at 20 ° C!
The commercial argument which says: "how to explain the 250 customers of my supplier prospected only in Bordeaux and its region, all installed in water-water heat pumps on groundwater" is a joke, moreover they are prospected customers, are not no buyers, you can't verify what he says anyway, so why not lie! In addition, it is not because there are customers that it is not a scam ...

BELIEVE ME IT IS A SCAM at 28000 euros!

"But then NO groundwater geothermal installation works in France then? And if I follow your reasoning correctly (delta T> 7 °), it does not work in Sweden either?" - No, geothermal installations on groundwater do not work with a good yield neither in France nor elsewhere, EXCEPT IF YOU HAVE THERMAL WATER at 20 or 30 ° C, or even more ... In Sweden there is lots of hot springs!
Obviously it suits.

For "@Ahmed : for the flow rate, according to my simple calculations with a 200 liter container, the flow rate of my pump is greater than 5 m3 / h. "- I think you are confusing the flow rate of your circulator with the flow rate of the source hot at (7 ° C), it has nothing to do with my calculation which is correct.

A heat pump is only interesting in mid season, and still it must be air-air ... or air-water ...

Good ecological and profitable heating is a good wood or pellet stove ... With solar thermal and / or electric backup.

Note: I live in a lot and Garonne.
A + friends

@Cortejuan : if I understood everything correctly, the heat is taken in the drilling water, which leaves in my region at 13 ° C and which emerges from the heat exchanger at around 9 ° C, i.e. a delta T of 4 ° vs. With this heat, the heat pump is capable of producing hot water at 60 ° C max with an electrical back-up.

Isn't that the principle of any CAP?

@DanielJ : but then NO geothermal installation on groundwater is working in France then? And if I follow your reasoning correctly (delta T> 7 °), that doesn't work in Sweden either? Or else I didn't understand anything about your demonstration. But how can I explain the 250 clients of my supplier who are prospected only in Bordeaux and its region, all installed in water-water heat pumps on groundwater ??? There I do not understand ...

@Ahmed : for the flow rate, according to my simple calculations with a 200 liter container, the flow rate of my pump is greater than 5 m3 / h. If I haven't forgotten my math lessons, that's 5000 liters an hour, right? If I follow the calculations of DanielJ, for a delta T of 4, we would need a flow of 3 or 4 m3, so its pass?

Or do we not live in the same region?

[raymon]

when the outside temperature is around 15 ° C, and the inside temperature around 21 ° C. There the cop can be from 2 to 4.

Very cloudy weather outdoor temperature 11.4 consumption 239w setpoint 21 °. I specify that there is never a peak consumption or stop on this machine this morning at 7:30 am it started at 900w then fell gradually in the day 2 hours to be at 350w
There the explanation of the operation of the machine:

https://www.econologie.com/forums/post253924.html

2 solution or my power meter is wrong or you are wrong.

[danielj]

Hello friends.
At the start I only spoke to answer the subject of the geothermal heat pump, not efficient enough to make a profit!

Now we're talking about something else. In the example proposed below, there is no contradiction with what I said. that the consumption of the system varies between 900w and 239w, this is normal. But there is no guarantee that the COP is high!
The COP drops when the outside temperature is low compared to the inside temperature AND when the outside temperature drops near a few degrees C (5 to 7 ° C) due to the GEL of the outside exchanger. This is the whole issue we are talking about.
Note for usual devices, the COP is maximum when the outside temperature is equal to the inside temperature and equal to around 20 ° C!
I very carefully reviewed the technical documents of professionals, as well as my many courses in physics, electrical engineering and thermodynamics ...

I'm going to use the motto of "Ahmed" which amuses me a lot "Please don't believe what I'm telling you.")

Your watt meter is right, me too ...

when the outside temperature is around 15 ° C, and the inside temperature around 21 ° C. There the cop can be from 2 to 4.

Very cloudy weather outdoor temperature 11.4 consumption 239w setpoint 21 °. I specify that there is never a peak consumption or stop on this machine this morning at 7:30 am it started at 900w then fell gradually in the day 2 hours to be at 350w
There the explanation of the operation of the machine:

https://www.econologie.com/forums/post253924.html

2 solution or my power meter is wrong or you are wrong.

[Gaston]

The COP drops when the outside temperature is low compared to the inside temperature AND when the outside temperature drops near a few degrees C (5 to 7 ° C) due to the GEL of the outside exchanger.

For an exchanger placed in an air flow, this is perfectly fair, but I do not see how an exchanger supplied with large quantities of water at 7 ° can freeze ...
At worst, it is enough to stop the heat pump by leaving the water pump running and it will melt very quickly.

On the other hand, indeed, the COP with already cold water is probably not famous

[Ahmed]

As you noted DanielJ, my comment was not about the pump flow, but about the ability of the well to provide the necessary flow ...
My other remark, more important to me, has been ignored ...

Glad you liked my signature: I chose it very carefully and not by chance!

The heat pump is a completely paradoxical machine in the use that is made of it for the heating or air conditioning of a residential building: it would be perfect for cooling winter and for heating summer ...

[raymon]

Now we're talking about something else. In the example proposed below, there is no contradiction with what I said. that the consumption of the system varies between 900w and 239w, this is normal. But there is no guarantee that the COP is high!

You make me laugh with your cop of 2 even the Chinese air conditioning do better.
For several days I have been heating up to 20 ° with 5kwh per day. 900w is for half an hour when the room is at 16 ° at this time when the room is at temperature it never exceeds 400w! Except in extreme cold it is not more expensive than wood or the need for a stove.

Monthly average of December in PACA11 ° at Bordeau 10 ° the entire Atlantic coast is 9 °! and there an air conditioning it works super well.

http://www.meteopassion.com/moyennes-de-decembre.php

[Aumicron]

Monthly average of December in PACA11 ° at Bordeau 10 ° the entire Atlantic coast is 9 °! and there an air conditioning it works super well.

Beware of averages!

Since you take the example of Bordeaux, since the beginning of the month 1/3 of the minimum temperatures are negative and practically all are below 5 °. What is important is the number of hours in a month where the temperatures are below 5 ° and even in Bordeaux this number is high.

In a simplified way, the demand for heating is greatest between 17 p.m. and 8 a.m. and it is precisely at this moment that the heat pump slips due to too low outside temperatures.