Solar or aerothermal in EJP?

[totoche]

Hello everyone

After going through a (small) part of this forum, I signed up
My problem: I live in a 135 m2 house heated by gas (half with underfloor heating, the rest with central heating)
I live in the Puy de dome at around 300 meters above sea level roof facing south at around 30%
I am in EJP tariff

I cogitate to reduce my gas bill, and I arrive at the following choice is it better in addition to my boiler
an air water cap
or a solar system

The second case has the advantage of being almost static so almost wear-free, unlike the CAP, the tax credit is 50%
The system that I am offered does not contain glycol (AQUA system) is this reliable

The installer offers me a 10m2 panel and a 600 liter tank is enough. Are there any risks in summer if the installation is over-sized?

On the heat pump side, the output seems higher, but maintenance must be added.

If you could bring me elements to decide me it would be nice

thanks in advance

[Christophe]

The system that I am offered does not contain glycol (AQUA system) is this reliable

I do not know the "AQUA system" but I know the drain system well since we have one.

I advise you to read this (to start): https://www.econologie.com/forums/systeme-so ... t8197.html

The installer offers me a 10m2 panel and a 600 liter tank is enough. Are there any risks in summer if the installation is over-sized?

There is no risk with the drain system: no pressure build-up possible and if the tank is too hot, the system can be stopped.

On the heat pump side, the output seems higher, but maintenance must be added.

Quite the opposite: the efficiency of a solar system is much, much, higher than any heat pump !!

The COP of your CAP will be around 3 to 4 at best.
Your solar system will have a COP between 70 and 100.

Ours has a COP of 75 when he is 25 years old !!

Threshold flat: your heat pump will be able to turn 24/24 but not your solar system. Without the sun, the solar does not work but a heat pump if ... the ideal would be maybe to have the 2 ... (an air-water heat pump of swimming pool that costs 1000 € but that does not make high T ° for ECS or with difficulty). So the productivity of the cap will actually be better but not its yield!

The electric bill of the heat pump will be much higher than that of solar compared to the energy supplied (ratio of 75 to 100 divided by 3 to 4) therefore in the "worst" case (for solar) 18 times higher in the best 33 times! These are obviously orders of magnitude to be refined on a case by case basis!

A PAC is still electric heating "less worse". So for me there is no photo: it is the solar that must be chosen but this is only my opinion.

Feel free to search here: https://www.econologie.com/forums/search.php

[aerialcastor]

With 30% or 16 ° roof pitch in winter you are far from optimal. By cons summer it will give

Can't you put your sensors on the front?

[totoche]

No possibility of installation on the front (windows)

No possibility of mounting on a support at ground level (in the shade by another building)

[Christophe]

If the sensors are tubes, the inclination is less important ...

[aerialcastor]

yes but not the price nor certainly the lifespan. But it is sure that it is not prohibitive.

[Christophe]

The price is now the same if you take "1st price" ... a Viessman with heat pipes it is sure that it is more expensive it is beautiful on paper but it has no economic interest!

For the lifetime: if emptying, no problem ...

Here is a suggestion: if the tubes are mounted "horizontally" on the roof then the slope of the roof (almost) no longer matters and productivity should be smoothed out over the year ... but not over the day on the other hand.

It should be seen if attempts in this direction have been made. KK1 has heard of it?

[tigrou_838]

Hello,

totoche, just a quick question, the ejp price is also for gas ??????? I thought it was for electricity.

that can change all the data of the problem that you have.

tigrou

[totoche]

All in all the EJP is for the EDF not for gas. I just pointed it out to take it into account for consumption on the 22 peak days (especially in the case of the cap) (I suppose that the solar circulator has a very reduced consumption)

[tigrou_838]

ok thank you, your hot water, you produce it how at the current time.

also with gas or electricity in the ejp

ps, in your case, I will do:

1 / solar, for heating and I will keep the gas boiler for days without sun, especially since you already have underfloor heating I thought I saw that in your first message.

2 / solar for domestic hot water, with electric backup in off-peak hours.

tigrou