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Example of metering of a PV heater for the production of hot water with diversion of PV surplus


I installed 2x 290W PV panels coupled with a 600 W microinverter over the summer, I was able to follow my production with an EmonPi. With the use of the app My Solar, I was able to determine that 80% of my production was exported to the grid (August-September 2021)

As a result, I decided to install an electric water boiler (15L) and a solic 200 from Earthwise products to divert my excess PV production for the production of hot water in parallel with my existing gas boiler.

Last month, I was able to get most of my hot water from my PV diverting system and the resulting export production was reduced by about 50%.

I switch from the existing gas boiler to the PV fed electric boiler with a simple 3 way valve controlled by a thermostat.

It works pretty well so I thought it would be interesting to share with others.

To me, this is a good alternative to either batteries or conventional solar water heating systems

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