[Andrew K Fletcher (OP)]

Ultimate test was performed today by my wife and I.

Yes, we both had our first thermal solar panel only shower and we had ample hot water. Now we really start saving money

[Andrew K Fletcher (OP)]

Suggested Improvements / modification

Goin to use a 50 metre coil of black mdpe pipe at least 22mil bore, I would then cut a circle of polycarb sheet to increase the heat of the tight coil of black tubing. This will give you additional heat in the winter and prevent freezing. Going to add a circle of corrugated steel sheet thermally insulated under it and painted mat black on the upper side and foam insulated on the bottom. This will increase the amount of pre heated water stored.

May even prove to be a cheaper solar panel for people who can't be bothered to solder copper pipes.

Thought about installing a tank as suggested by others. But the downside of this approach is that many hours of sunlight would be required to heat the water to warm, and this will inevitably be relying on electricity to increase the temperature whereas the direct tank-free system heats up in 15 minutes of direct sunlight after being completely emptied of hot water. Short bursts of 15-60 minutes of sunshine in the UK is about all we can expect as a constant most days, so this system is going to be more productive in providing our instant hot water usage.

Electricity and gas bills are due tomorrow. We have 6 monthly bills and our solar panel has been supplying hot water when the sun shines and even warm water when the sun is hidden behind cloud cover, for 4 months of our half yearly domestic use.   Stay tuned for my next report and a comparison of the previous years bill.

[Andrew K Fletcher (OP)]

6 Months Gas and Electricity

Last Year Electricity Units Used:   1717

This Year Electricity Units Used:    1509

Units Saved:             208                  Savings =     £29.23p


Last Year Gas           Units Used:    83

This Year Gas           Units Used:    73

Units Saved             10           Savings =     £14.08p



Total Savings:                          £43.31   

Annual Savings based on these savings over 6 months.                     £129.93

Cost of DIY Solar Panel, excluding new shower thermostatic taps            £116.00

Estimated Annual Profit   May be less or more depending on sunlight            £ 13.93



Savings are from 4 months since installing the Thermal Solar Panel and very poor summer weather with it being rain or overcast on many days. Even so the savings so far speak for themselves.

[lyner]

That's very impressive AKF.
The next big step is to incorporate it into your main system. That's what costs the GBP so much that they're not all doing it.
Idiots in government don't seem to know the word SUBSIDY.

[Andrew K Fletcher (OP)]

This is incorporated directly into the hot water system and operates under mains pressure feeding hot water into the combi-boiler inlet. That's the whole point, this system is installed and running for just over a hundred pounds.

Are you refering to running another solar panel into the central heating system? If so that is taken care of with a log burner savings from which are in excess of £700 per yesr.

[Andrew K Fletcher (OP)]

Next move is to encorperate a 50m x 20 - 27mm coil of black mdp on flat roof, sandwiched between mat black corrugated steel sheets, lagged on back with polycarbonated tri ply sheets on solar side. This is in effect the same set up as the solar panel so should work well and will be insulated instead fo the exposed black pipe.

Using the larger bore pipe will give us lots more pre heated water. Also considering tilting the corrugated sheets slightly to pick up more energy from the sun.

This system is highly efficient as it is, our water is piping hot and we are noticing savings already.


PS   inventing a new device, Need patent in place before I can tell you more, nothing to do with solar panels btw

Stay tuned for more

Andrew K Fletcher P.G.P. (proud grand parent) 

[Andrew K Fletcher (OP)]

Been running for over a year now producing water at around 78 degrees, sufficient for showering and filling up the washing machine to save money on electricity. It did freeze in the winter a couple of times but did not burst and quickly defrosted when the sun came out

All in all not a bad investment that will run for many years to come.

[norcalclimber]

I live in Sacramento, CA and the apartment complex I've been living in for the past 3 years actually uses a very similar thing to provide most of the heat for their spas.  The pool area has a large rectangle gazebo structure, and the top of it is covered with black PVC pipe running back and forth for the length of it.  The water is then run to the heater, and then to the spa.  This seems to save them considerable money on heating the spas, and has been in place for several years now at least. 

Your approach seems to be an excellent one, and I think I may have to put it in place for my mother, who is lucky enough to own her home.  She also has a 5kw solar system, which helps...but the 2 water heaters she has suck up a lot of that power, even being on timers.

[imatfaal]

Andrew

Absolutely brilliant - I knew it would work in Mediterranean climate (done by many in Greece), but in the UK this is fantastic proof of principle

Congrats - enjoy your savings!
Matthew

[Andrew K Fletcher (OP)]

Thank you for your encouraging words.

Update 2011  After a prolonged hard frost the system froze. I had closed it down but forgot to drain it over the winter Doh

Every joint on the copper tubing required re-soldering and took ages to clean the top joints. Then I remembered that vinegar stripes off the oxidisation so threw the rest of the joints in an old pickled onion jar and topped up with some fresh vinegar. Worked a treat and saved hours of work cleaning the joints.

Got some evaflux and some lead solder which works well and lasts far longer than the lead free solder which was used initially.

Also purchased a thin sheet of polycarb to replace the perspex, more to make it aesthetically pleasing but should prove to be more functional after the guy selling it pointed out that the air pockets between the polycarb would reflect the energy from the son onto the corrugated steel sheet more effectively which sounds plausible.

Will update some more shortly.