Cyprus-Forum.com

[kurupetos]

Solar water heating in the world: Strong diffusion due to the large impact of incentives

Cyprus is the world leader in terms of capacity per capita, followed by Israel, due to high solar radiation and support policies. More than 90% of households are equipped with SWH.

http://www.leonardo-energy.org/solar-wa ... incentives


...Time to move on and become world leaders in nuclear energy...

•There is revival of interest in small and simpler units for generating electricity from nuclear power, and for process heat.
•This interest in small and medium nuclear power reactors is driven both by a desire to reduce the impact of capital costs and to provide power away from large grid systems.
•The technologies involved are very diverse.

http://www.world-nuclear.org/info/Nucle ... -Reactors/

[Paphitis]

...Time to move on and become world leaders in nuclear energy...

After Mari, I will be happy to be living as far as possible from Cyprus as I can get!

[bill cobbett]

Ah, a new and potentially interesting thread from Toffoui, perhaps he's turned over a new leaf for the New Year.

An interesting thread cos some questions on solar power in CY have been on BillC's mind for a few days.

So the questions...

You know those white plastic water storage tanks or or deposita on the roofs in CY ?

Why are they white, which reflects sunlight ??? If they were painted black, they would absorb more of the Sun's energy and contribute more to water heating. ... so why are they not painted black...???

[kurupetos]

@ BillC
The color of the water storage tanks doesn't really matter, because radiation heat transfer occurs through the flat plate collectors which are facing the sun.

And yes the collector assembly is usually black, whereas the water storage tank only needs to be well insulated to minimise heat losses.

Simples, dear goblin...

[bill cobbett]

@ BillC
The color of the water storage tanks doesn't really matter, because radiation heat transfer occurs through the flat plate collectors which are facing the sun.

And yes the collector assembly is usually black, whereas the water storage tank only needs to be well insulated to minimise heat losses.

Simples, dear goblin...

Yes, ok... but what if there were no black flat plate collector assembly and no insulated copper cylinder.... just the uninsulated plastic water storage tank, would the water in it get hot/hotter and hopefully stay warmish overnight if it was painted black...???

[Get Real!]

Why are they white, which reflects sunlight ???

The white plastic ones are for your cold water so they fill up straight from the mains and *should* be installed in your roof if you’ve got one.

For the hot water it's those smaller nickel plated ones which are also dual... a tank within a tank to preserve heat.

http://www.metalcoheaters.com.cy/enUS/P ... fault.aspx

[Get Real!]

@ BillC
The color of the water storage tanks doesn't really matter, because radiation heat transfer occurs through the flat plate collectors which are facing the sun.

And yes the collector assembly is usually black, whereas the water storage tank only needs to be well insulated to minimise heat losses.

Simples, dear goblin...

FAIL

[kurupetos]

@ BillC
The color of the water storage tanks doesn't really matter, because radiation heat transfer occurs through the flat plate collectors which are facing the sun.

And yes the collector assembly is usually black, whereas the water storage tank only needs to be well insulated to minimise heat losses.

Simples, dear goblin...

Yes, ok... but what if there were no black flat plate collector assembly and no insulated copper cylinder.... just the uninsulated plastic water storage tank, would the water in it get hot/hotter and hopefully stay warmish overnight if it was painted black...???

No, because in this case you would have heat losses when there is no sunshine (e.g. evening) and the water would reach ambient temperature within an hour or so.

Also it's a solar water heater, and not a thermal water heater, which is a different thing and cannot reach temperatures high enough for domestic water heating. The metal (e.g. copper) does all the heat transfer effectively because it has a high conductivity, whereas plastic has negligible conductivity.

Have a look here...http://en.wikipedia.org/wiki/List_of_thermal_conductivities

@GR! Go back to the closet.

[georgios100]

The problem is the positioning of the hot water tank on the roof of the house.
During cloudy days or at night, the heat loss is just too much!

The hot water tank should be placed inside the home, protected from the elements.
A small water pump, powered by a small solar panel circulates the water from the tank below to the roof collectors above.
When night falls, the pump stops the circulation automatically (no sun to power this pump).
The hot water stays hot and ready for use anytime. The next morning, the pump resumes as the sun rises...

[Get Real!]

The problem is the positioning of the hot water tank on the roof of the house.
During cloudy days or at night, the heat loss is just too much!

The hot water tank should be placed inside the home, protected from the elements.

Correct! I made the mistake and I’m wondering how much trouble it’ll be now to move it in the roof.