Landscape and Architectural Design

Currently in flower in my garden.
(Dahlia and Lily)


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What shall I do with my time now that I am retired ?
(I don't think that will be a problem)


01 AUGUST 2007


The solar panel on our roof is producing all the hot water we need at this time of the year.
We have a single collector panel on the roof consisting of 25 evacuated tubes each 1.5m long.
The system was installed just over a year ago and although we have had some teething problems, the system is working perfectly.
The problems were with the 12 volt pumping system that circulates the water from the collector panel to our hot water storage tank.
The pump is powered by a wet cell battery similar to a motor cycle battery and is charged by a small photovoltaic panel also situated on the roof.
In order to prevent the battery from 'overcharging' - it is necessary to include in the sytem an electronic 'charge controller'. This will allow the battery to charge to it's maximum capacity but not overcharge. It also prevents the battery from discharging via the photovoltaic panel during the hours of darkness.
The 'charge controller' fitted initially was the cause of the problem.
The firm that fitted the system seemed to have a poor knowledge of the electronics and just replaced the battery. This cured problem for a short time but the problem soon re-appeared.
After many telephone calls and and letters and engineers that failed to appear, I decided to try to cure the system myself.
First I obtained a new battery (a little bigger than the original/s) and I found that in spite of excellent weather (sunlight) the battery was loosing it's charge.
I checked the voltage from the solar panel and that seemed OK.
So I obtained a more sophisticated Charge Controller and fitted that.
The result is that the system now works perfectly and the outfit that intalled it is about to get a bill from me.

Photos are.....
1.        The collector panel on the roof
2.        The control sytem (set to switch on pump when collector temp. is 10degC above water temp.and switch of when collector temp. is 8deg.C above water temp.  Here the collector temp. on roof is 76 deg.C and the water temperature is 66.2deg.C. (bloody hot)
3.........The new Charge Controller

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