Hi guys,
A couple of months ago I installed 12m2 of solar collectors on our pergola next to the pool.
After a week of testing the panels were not collecting much heat. They are of an open tube kind (gaps between the small black tubes). With more than 100% coverage the temp difference between the input and output was only about 0.5c even at the strongest time of the day.
We always seem to have a lot of wind (cool) blowing across and through the pergola from the coast (100-150 metres from the ocean). So with a lot of wind, evaporation and high flow through the panels we weren't getting any results.
Reading around the subject I understood the loose tube collectors can lose as much heat as they absorb in windy locations.
So I built my own glazing! Insulation layer below the panels and a 4mm double wall polycarbonate sheet above them boxed in.
Seems to be working well now. Output temp is higher on the windy days now. Pool temp between now 31-35c. The new cover has greatly improved maintaining this temp as we had so much evaporation every week.
Other observation with the pool cover is that the chlorine levels have risen significantly. I had to have the SWG on max before now it is on the min setting. This is good on my electricity bill also!
I'm going to install 2 temp sensors and wifi switches for the pump.
This way I can monitor the heat of the sun next to the panels and also the pool temp from my phone.
Once the temp of the sun in the morning is higher than the pool temp it can switch on the pump.
Also if we get a strong shower or cool day with heavy cloud it can prevent the pump from circulating the water through the panels.
Unfortunately in Uruguay I can't get hold of automatic 3 way valves to make this easier.
Most likely during my next trip to USA I'll bring one back.
Next job: I'll be moving the panels to another roof and possibly increasing the area to 20m2 or more to work well at the end of the season.
Thanks
A couple of months ago I installed 12m2 of solar collectors on our pergola next to the pool.
After a week of testing the panels were not collecting much heat. They are of an open tube kind (gaps between the small black tubes). With more than 100% coverage the temp difference between the input and output was only about 0.5c even at the strongest time of the day.
We always seem to have a lot of wind (cool) blowing across and through the pergola from the coast (100-150 metres from the ocean). So with a lot of wind, evaporation and high flow through the panels we weren't getting any results.
Reading around the subject I understood the loose tube collectors can lose as much heat as they absorb in windy locations.
So I built my own glazing! Insulation layer below the panels and a 4mm double wall polycarbonate sheet above them boxed in.
Seems to be working well now. Output temp is higher on the windy days now. Pool temp between now 31-35c. The new cover has greatly improved maintaining this temp as we had so much evaporation every week.
Other observation with the pool cover is that the chlorine levels have risen significantly. I had to have the SWG on max before now it is on the min setting. This is good on my electricity bill also!
I'm going to install 2 temp sensors and wifi switches for the pump.
This way I can monitor the heat of the sun next to the panels and also the pool temp from my phone.
Once the temp of the sun in the morning is higher than the pool temp it can switch on the pump.
Also if we get a strong shower or cool day with heavy cloud it can prevent the pump from circulating the water through the panels.
Unfortunately in Uruguay I can't get hold of automatic 3 way valves to make this easier.
Most likely during my next trip to USA I'll bring one back.
Next job: I'll be moving the panels to another roof and possibly increasing the area to 20m2 or more to work well at the end of the season.
Thanks