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@tim441 Thank you.
We are at 300m2 and mid 70s vintage, but no UFH, so probably running with similar efficiencies. Although I keep my reference room at 19C instead of 21, which I prefer (I’d actually prefer 15C, but am alone on that in the household).
You do well to keep yours on a single TOU tariff, I can’t get away with that with just 14kwh storage and need to run cosy with the 3 slots, which works out at 14p. In my situation I struggle to justify spending another £10k on adding a further 28kwh battery storage to meet peak mid winter demand, the ROI on that extra spend would be decades.
@papahuhu yes, extremely hard to compare like with like.
We have 24.6kW batteries and with max charge/discharge rates at 2.7kW we can't fully operate at night rates. But the average over the year is still under 10p.
We even tweak thermostats 1 deg higher at night so that the morning demand at peak rates is reduced. Instead of a more normal setback.
So far I can't justify any upgrade of batteries size or charge/discharge... but clearly will need to be looked at if current system fails.
V2H/V2L/V2G will all need to be looked at in future I guess as that could be a gamechanger if easily integrated.
Listed Grade 2 building with large modern extension.
LG Therma V 16kw ASHP
Underfloor heating + Rads
8.7kw pv solar
3 x 8.2kw GivEnergy batteries
1 x GivEnergy Gen1 hybrid 5.0kw inverter
Manual changeover EPS
MG4 EV
@tim441 Here are those same three month periods for 2023, 2024, 2025 and this year. I hope they will appear in chronological order; the system seems to choose its’ own order sometimes!
Regards, Toodles.
Toodles, heats his home with cold draughts and cooks food with magnets.
@papahuhu just had a search for 100Green and your post came up - did you make the change to their Smart tariff?
I ask because I am on Agile and rates are pretty rubbish at the moment with overnight (tonight for e.g.) around 30p and not much below 25p tomorrow offpeak. Still some negative rates at the weekend if the wind is blowing but you can't rely on that.
So I was browsing the old GivEnergy forums and someone recommended 100Green and they have 7 hours 0000 - 0700 at just over 7p/kWh which would fill my 19kWh batteries nicely - and the EV as well. Day time at 34p but I could avoid the peak rates at 45p easily enough.
Just doing diligence before making the jump and interested if anyone else has experience to share.
Mitsubishi Zubadan 14kW with Mixergy 210l DHW in 220m2 barn property. 24 solar panels = 9kWp with GivEnergy 5.0kW Hybrid inverter and 19kWh GivE batteries. Jaga Strada fan-assisted rads throughout. Landvac vacuum glazing/triple glazed windows.
I was seriously considering Tide Lifestyle, it gave an extra hour off peak compared to octopus cosy. I eventual chose OE Cosy because the off peak rate is approx 1p per unit cheaper, however in reality, over the winter the two would have been comparable as mid winter I often need that extra hour.
I also stayed with OE as their export tariff is better for me in the PV months and it is very quick and easy to switch tariffs from within the OE account.
I just checked this morning and OE just raised their off peak fixed rate considerably, as I was expecting. I haven’t gone back to check 100Green, but it’s possible that they now are the most economical heat pump tariff if you need the 3 off peak windows.
And here we are with another month’s generation: Not quite as high as last September’s yield but quite respectable I think.
Here are the last four September readings. Regards, Toodles.
Toodles, heats his home with cold draughts and cooks food with magnets.
It was almost identical to last year for us. After a glorious summer the low generation months have arrived.
16 * 435 watts PV
13 kWh Growatt battery
1 EV - Mercedes EQB
6 kW Aira Heat Pump
Bosch Induction Hob
Pod Point Solo 3 charger
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Plug and play solar. Thoughts?
2 months ago
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Supplier choices for PV system
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Any advice for new solar installation? SW facing extension
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First 6 months
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