Solar panels can also directly heat water by heating water filled pipes within the solar panels or by heating a transfer fluid such as antifreeze usually propylene glycol.
Antifreeze solar panels.
This is not automotive antifreeze which is a different substance ethylene glycol and is.
Garrison advised that electrical hot water tanks work the best for solar hot water use.
Using an antifreeze solution.
Glycol or some equivalent antifreeze fluid fills.
Solar thermal panels collect solar heat and transfer it to hot water tanks.
Solar thermal panels are a closed system of tubes that contain a solution similar to antifreeze.
Closed loop active antifreeze systems are the most versatile and failsafe of all the solar supplemental water heating systems.
The antifreeze is normally non toxic propylene glycol as opposed to toxic ethylene glycol.
Most solar thermal systems use antifreeze as the liquid to transport heat from the solar panel to the cylinder.
Propylene glycol pg has become the most common heat transfer fluid used in closed loop solar heating systems that contain antifreeze.
It s non toxic biodegradable and relatively stable.
Should be sufficient for most single and double panel systems.
What type of solar system do you have is it sealed or drainback a correctly installed drainback system should not require antifreeze sealed systems require a good quality antifreeze that will not break down with the high temperatures of solar it should also be a premixed antifreeze it is no good injecting a small quantity of antifreeze into the system as it will not mix and so will not.
However there are a few drain back systems that only use water.
5 litres solar antifreeze.
Recommended dilution 40 providing total volume of 12 litres for use in solar systems.
The photovoltaic solar panels or pv solar panels convert the sun s energy into electricity which then can be used to heat water.
However you should always mix as much water as possible with your choice of glycol product as simple water is the ideal solar fluid.
Neat propylene glycol with additive package.
The industry standard for solar fluid is a mix of propylene glycol and water.
Most new solar homes feature a variation of one kind or another.
Antifreeze fluids degrade over time and normally should be changed every 3 5 years.