Posted by jan siepelstad on May 17, 2008, 6:14 pm
I have a 15 kWp PV system on my roof.
The panels tend to get quite hot in full sun.
Because of the reduced output from high temp. panels, I thougt it might be
usefull to put garden sprinklers on my roof, to distribute water over the
I have free water available from a small stream in the back of our house.
So it would cost met just the energy for a pump.
Offcourse the energy gain should be more than the pump energy.
Has anyone in this group ever experimented with something like this?
And if yes, what were the results?
Jan (from Holland)
Posted by Phil Ross on May 17, 2008, 7:50 pm
How do you plan on preventing or removing the mineral deposits that may
result from the water evaporation? Granted, well water would probably be
much worse than using water from your stream, but you may have to deal with
"hard water" spots over time which may cancel out the increase due to the
Posted by BobG on May 17, 2008, 8:11 pm
It should be easy to measure.... hook up a voltmeter and ammeter
(wouldnt it be great id they were rs232 out and you could record the
data?) and get some readings in the sun, then turn on the water. Go
back and calc power out in ea case and see if it goes up. If it goes
up by more than the size pump you need, you are 'in the black'.
Posted by Eeyore on May 19, 2008, 6:31 am
Aside from the cost of purchasing and installing the extra kit of course
I'm always intruiged that PV solar supporters ignore capital costs when
assessing comparative results. It's probably the only way they can even
remotely break even (in their minds).
Posted by Ken Maltby on May 18, 2008, 2:43 pm
The cost of the equipment is amortized over time, if cooling
actually extends the useful life time for the panels (a much
greater capital expense) you would easily cover any cost from
purchasing and installing "the extra kit".
Advocates exaggerate, that is a fact of life.