What are the advantages of using a Controller?
The purpose of the controller is to optimise the efficiency of your solar panel and to ensure heat is not wasted unintentionally. With controllers starting at around £35 they are to be recommended strongly. A controller is also very useful if you wish to use PV power. The most effective method is to use the photovoltaic panel to maintain charge on a 12-volt car battery and to power the pump and controller from that battery. This set up gives the best performance from your solar water panel without consuming any mains power. Tip: Your local vehicle dismantler will have lots of good 12V car batteries that they need to get rid of. I usually reckon to pay around £10 for a heavy-duty battery or even less for a smaller model. As a guide, a 48 Amp/hr battery would run my pump for over 90 hours (about a fortnight) without any charge from the PV panel.
