In
                                  its contribution the solar thermal panels take
                                  some of the pressure off the heat pump as they
                                  have already done some of the necessary early
                                  work in order to increase the temperature within
                                  the system; it means the heat pump is in effect
                                  getting a head start or a ‘leg up.’ Without
                                  having to set off from a ‘standing start’ this
                                  means the heat pump doesn’t have to work
                                  as hard. It is a bit like the difference between
                                  boiling a kettle when filled from the cold
                                  tap to boiling a kettle when filled from the
                                  hot tap.  
                                The
                                    reduced running time coupled with the smaller
                                    degree of work required from the heat pump
                                    increases COP of the heat pump and complete
                                    system respectively. This ultimately results
                                    in less electrical energy consumed by the
                                    heat pump and indeed less electricity to
                                    pay for! 
                                To
                                    further increase on this already efficient
                                    heat pump and solar thermal combination,
                                    why not add some solar PV panels to the mix
                                    and create your own electricity. Solar PV
                                    panels can be on your roof in your garden
                                    or even on your walls. See solar
                                    PV section. 
                                  
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