Performance and efficiency of a solar thermal system

[keke]

Hi Nicolas,

Thanks for the compliment.

A + on APPER

Keke

[zorglub]

[In winter, the production will start later if we have not drawn ... the production will also stop earlier because the sun is declining, the capture temperature will also fall quickly, ending the transfer to the storage tank. ]

to put an end to these inconveniences I installed my ECS exchanger (150 l) upstream of my electric cumilus which I kept
thus: the solar preheat the water of the cumulation (70l) and as soon as it reaches 60 ° the thermostat of the solar balloon cuts the electricity on the cumulus and I use at the maximum the solar energy loresque I exceed 75 ° a solenoid valve bypass the solar flask and reject the liquid exchanger into the expansion tank
the solar circulator starts as soon as the temperature of the collectors reaches the water temperature of the solar flask

nb: I can only use my cumulus by isolating it from the solar by a valve

[Did67]

I reactivate this old thread, because I took a little time to "auscultate" my old installation today ...

The forums, if they are full of "theoretical returns" ("up to 50% savings ..." etc), they lack real data!

- CESI De Dietrich installed in autumn 2002
- kit with 2 panels of almost 5 m² and a double coil coil of 300 l
- complement: up to and including 2007, fuel boiler, then pellet boiler (two xerpentins balloon, the upper coil is dedicated to the boiler)

A quick report:

- incident: none; nevertheless, today, one of the two panels is no longer 100% waterproof, hence, after a period of rain, condensation on part of the glass inside; hence loss of yield [nevertheless, even in changeable weather these days, that's enough! Boiler stopped; this must be "missing" in shoulder season]

- the box included counters (pump operating hours, estimated power, taking into account the "theoretical" power of the panels: surface and orientations and specific characteristics); these counters are intulizable because ... limited to 4 digits! They are therefore "exploded" today; one blocked at 9999, the other indicates a number but we do not know what is the counter of tens of thousands ...

- fortunately, there is a "beast" water meter, mechanical, in the heat carrier circuit, which works for him

- "cross - checks" made in 2005 then 2007 at the request of an interested friend showed me that the indications of the electronic meters and the calculation made on a very simple basis: volume of fluid passed through the meter X heat capacity X difference mean of 15 ° give consistent "orders of magnitude"

So based on the meter, and with this method, I arrive today, after 12 years, 2 259 m3 having circulated in the circuit.

The difference of 15 ° seems like a mini (the regulator starts and stops the pump as soon as the difference between the top and the bottom is 12 °; but at midday, the difference greatly exceeds 15 °; therefore I think this is a "conservative average").

All calculated, this would correspond to a "collection" of about 40 kWh.

The installation cost me 4 450 euros (aid deducted), we see that roughly, after 12 years:

- it would be "amortized" (the investment would be recovered) if I used electricity (average price of 11 cents including tax per kWh over the period; it is now around 13,5 real cents including tax at home: invoice including tax / consumption at the meter; do not be fooled by the "displayed" prices, generally excluding a typed tax at the bottom of the invoice)

- it would not be quite with fuel (about 7,5 cents per kWh)

- it is not at all with pellets (about 5 cents per kWh).

For those who are still thinking.

Ah, I forgot: I'm in Alsace.

[Did67]

Small additive: I unfortunately do not have a specific electricity meter at CESI.

But I have to reread the consumption of my circulator [alas, a device from the "old generation", before high performance neodyne] and with the number of hours of operation, I could also make an energy balance, without however the embodied energy of the installation ...