Many households prefer not to export their surplus electricity to the grid. In Ireland there is no payment for exported power, and it is simple and easy to use this surplus to provide solar hot water.
You can install a PV system to heat water for a lower cost than most solar tube systems, with the advantage that there is no need to change the cylinder, no water system running up to the loft requiring regular maintenance or anti- freeze.
In the UK and elsewhere, numerous diversion devices have been developed to use your surplus electricity from a solar panel or wind turbine to heat water in the immersion cylinder. These different systems have pros and cons. Please talk to us about which unit might suit your situation.