Building a Solar Collector: Linking Theory to Practice

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also, i am unsure about the units...are the above ones ok? as in the website had these units [ KWh/m^2/ hello everyone!
i know that solar collectors are commonplace in many parts of the world (tho not mine) so this might sound a bit stupid...

anyway, i wanted to make (actually build) a solar collector and am finding it hard to link theory with practice...anyhow, my dsegin is simple having a copper pipe run through a wooden frame. On top of the base (wooden) lies the absorber (which i hope to make out of a copper sheet 1m x 1m with a semi-circular trough all the way in which would be placed the copper pipe (which if i can, i would attempt to also get welded to the sheet) ). On top of the frame lies a sheet of glass which would, if the theory is right, create a greenhouse effect in the collector for the temperature of the water to rise as much as possible

i am planning to make a 1m x 1m panel. the thickness would depend on the diameter of pipe available to me but i hope to have it around 0.5 inch to 1 inch.
A rough sketch, I am pasting below…
so,
first, i would like someone with expertise to verify if the design is fundamentally sound. My problem is that my budget is limited, so i don't think i would be able to make and then remake, tho minor tweaks should be okay
second, i am assuming that the power/meter the surface of where the collector will function to be around 5 KWh/m^2 (this is based on the arithmetic mean of data for a place near my exact location i found on the internet from that available for each month)
day ]
third, it would really nice if someone helps in getting all the details right by pointing it out here...
[I am looking to heat the water to as high a temp as possible with 1m squre panel, tho a 20 to 70 degree differential would be fantastic…again that would depend on the efficiency of the collector (which I guess can only be calculated after the thing is made), the ambient irradiance, mass flow rate (which I think might depend on the pipe diameter) etc etc]

Thanks in advance
 

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mgb_phys said:
Not sure 1in copper pipes are the most cost effective, you generally want very thin pipes so that as much water as possible is in contact with the walls.
Noted:smile:

mgb_phys said:
And a 1m x 1m copper sheet isn't going to be cheap (unless you already have it)
hmm...actually i don't have one...can you actually tell what material might be better (cheaper and acceptable) as an absorber??

howtopedia (www.howtopedia.com) mentions copper, aluminum, steel and 'plastics' as potential absorbers. i doubt such plastics would be available over here...but can u mention any other materials??

mgb_phys said:
There are a low of solar hot water project sites on the web eg.
http://www.builditsolar.com/Projects/WaterHeating/water_heating.htm
i had been to that website, in fact to many others, but i couldn't find that detail i want to make the panel
 
I think I would get one of the books suggested on that site (or the ones it links to) before you start buying parts.
Most of the home projects seem fairly cheap/simple.
If you live somewhere that freezes part of the year it might get a bit more complicated