Five years ago I installed an Intelligent Immersion solar diverter. This small piece of kit diverts any excess PV energy which would have been exported to the grid into our immersion tank, thereby creating hot water.

Here is the original article about the piece of kit.

The unit has been absolutely brilliant, working any time of the year even in mid-winter, at heating the water in our immersion tank, thereby saving us the cost of oil or electricity to heat the water.

Sadly the unit failed last week and I contacted the manufacturer, Intelligent Immersion, to see if they could help in diagnosing the fault. On speaking to them it became apparent that there was a design fault with the fuse holder, and they offered to repair my unit FREE OF CHARGE, even though the 3 year warranty had expired.

They currently have a Spring Offer available. The unit is now available for only £189, significantly less than the £250 original cost. If say an average 3KW per day is diverted to your immersion, the payback is probably a year or less.