solar self consumption device.....

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I am considering solar for my large south east facing roof, I know Im not going to save the planet on my own but every little helps.
I have mains gas heating, & a large hot water tank with two immersion heaters installed.(economy 7 style)
As fits are low my main objective is self consumption, so to this end a solar diverter to hot water is a good start, someone working from home three days a week(office/ computer) is also useful, but I think I recall device that could divert excess to another device ( resistance heater/oil filled rad) but cant for the life of me remember what its called, can any body help? also any other ways to self consume? we have delay timers on our dishwasher & washing machine so thats another idea
TIA. nologo
I have mains gas heating, & a large hot water tank with two immersion heaters installed.(economy 7 style)
As fits are low my main objective is self consumption, so to this end a solar diverter to hot water is a good start, someone working from home three days a week(office/ computer) is also useful, but I think I recall device that could divert excess to another device ( resistance heater/oil filled rad) but cant for the life of me remember what its called, can any body help? also any other ways to self consume? we have delay timers on our dishwasher & washing machine so thats another idea
TIA. nologo
Deepest Kent. 4.6kw Growatt inverter, solar i boost+
ok so far...
ok so far...
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To put all this into context, I have a 7kWp array and a 13.5kWh Powerwall 2. In December last year, my daily output varied from 350Whs to 10kWhs. I would be hard pressed to meet home needs; reheat a HW cylinder and power a radiator with an output of 350Whs.
2.72kWp PV facing SSW installed Jan 2012. 11 x 247w panels, 2.5kw inverter. 28MWh generated, long-term average 2.6 Os.
ok so far...
Some argue that exporting your surplus locally generated solar energy to the grid, and using your gas boiler to heat domestic hot water, is more environmentally sound than using that locally generated solar energy to heat your domestic hot water through an immersion heater. I carefully avoid having any opinion on the environmental merits, because I am on deemed export therefore it saves me money.
Edit: The other thing to consider is that if you run your immersion heater around the middle of the day you may well be generating more spare electricity than the 3.68 kW most of us are allowed to export so you are being payed 0p per kWh for that even if you can get 5p per kWh for what you can export. Can you set the iBoost or the eddi to siphon off spare electricity once the export gets to 3.68 kW I wonder? That's the economic logic of what @QrizB is saying.