A few weeks  ago I wrote about the installation of the solar panels that had been kindly donated to us a few years ago.     Since then progress has been good.  The panels have been mounted on south-facing racks, the water connections made and some minor leaks repaired.  The connection to the pool water circuit was made for the first time on the 31st July and we switched on the pump (temporarily) to see how the system worked.  Pleasingly we are getting a flow rate of 1.5 m3/hr passing through the panels so we are quietly confident that when the sun shines we will be able to get the energy collected by the panels into the pool.  Sadly it was cool and cloudy when we tried the pump so we weren't able to get any heat into the pool.   The next step is to assemble a control system that will switch the pump on when the panels are hotter than the pool and switch it off when the they are cooler .  The panels will act as radiators as well as solar collector so we don't want to run them when it is cold (overnight for example).  This means we need to measure two temperatures and have the ability to operate a mains switch.  In addition we also want to measure the amount of water we put through the panels.  Then we will be able to calculate the power the panels are generating and the amount of heating fuel we are saving.   As the project progresses I will keep you informed.