Link pv into immersion heater first before feeding back into the grid

[SRE]

I've got a customer who wants to maximise their payback by using the electric generated in the summer to top up the immersion heater during the peak daylight hours - how on earth do you do that

 

[SolarCity]

It'll happen automatically. Put the immersion heater on a timer and set it for the daylight hours and the electricity will be used at the customer's place before feeding excess to the grid.

 

[SRE]

I did think about this, the only thing is if the sun isn't shining then it's going to be taking directly from the grid but I suppose if they are topping it up from night time use that would happen anyway. The dilemna is if they don't use nighttime electric to heat the immersion heater it could cost quite a lot to heat the water on a dull day drawing electric from the grid.

 

[malcolmsanford]

Wouldn't a solar system be more efficient for them?

They are specifically designed for immersion tanks and heating hot water, if the use of PV was thought of as efficient enough to work like they are asking, then wouldn't something have been brought onto the market by now, and redeucing the use of solar panels for heating water?

 

[SRE]

Thanks, I must have read your mind - I've just emailed them to suggest that solar thermal would compliment the pv perfectly. Thye certainly have enough roof space. I just don't want to lose the pv sale to thermal because we don't do thermal.

 

[noidea]

There is a system called an EMMA. Basically instead of the excess power being exported back to the grid and the customer getting only 3p for their trouble the EMMA will divert the power to another source, ie an immersion. They can be bought from a company in Ireland, Coolpower Products UK - Smart Sustnainable Energy. I believe they cost around £1500 but I'm not sure,
Hope this helps

 

[PeteC]

You could set up a control circuit monitoring the PV output and operate a contactor switch for the immersion...