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Upgrading my system, how far do I go?
@old_scientist Thank you, I've found out that the Sig battery charges/discharges at 4.5kW, so I would need two to get 9kW, which I think would probably be ok. The largest draw I found in my data on a cold day was 9.5kW, but that wasn't common and it was towards the beginning of the Cosy 1pm - 4pm cheap period when we would have been load shifting.
@majordennisbloodnok The more I think about the North roof Solar PV the less sure I am, but the additional south facing low roof and the west wall I'm more and more certain of, will try modelling different scenarios. Thank you for the info on alternative inverters/batteries that is a very valid point, I'm still quite keen on Sig for a variety of reasons, but yes there is a concern there following what happened to GE, I'll research to see what other options are out there.
Mitsubishi Ecodan 8.5kW
4.4kW Solar PV
5.2 kWh Battery Storage
1983 build, 300mm loft insulation, cavity wall insulation (beads)
Posted by: @trbob...
@majordennisbloodnok The more I think about the North roof Solar PV the less sure I am, but the additional south facing low roof and the west wall I'm more and more certain of, will try modelling different scenarios. Thank you for the info on alternative inverters/batteries that is a very valid point, I'm still quite keen on Sig for a variety of reasons, but yes there is a concern there following what happened to GE, I'll research to see what other options are out there.
Not a problem, @trbob. Whatever you decide, if your choices are made with wider information available then I'm happy.
105 m2 bungalow in South East England
Mitsubishi Ecodan 8.5 kW air source heat pump
18 x 360W solar panels
1 x 6 kW GroWatt battery and SPH5000 inverter
1 x Myenergi Zappi
1 x VW ID3
Raised beds for home-grown veg and chickens for eggs
"Semper in excretia; sumus solum profundum variat"
Posted by: @trbob@old_scientist Thank you, I've found out that the Sig battery charges/discharges at 4.5kW, so I would need two to get 9kW, which I think would probably be ok. The largest draw I found in my data on a cold day was 9.5kW, but that wasn't common and it was towards the beginning of the Cosy 1pm - 4pm cheap period when we would have been load shifting.
For comparison, my PW3 with 11.04kW inverter, will charge at 5kW (or 10kW if you add a second battery / expansion pack) and will discharge at the full 11.04kW (can actually do 11.5kW max when off grid I believe). I know you said you are not so keen on the PW3 - I'm biased 😊
It is important to understand such things if they are going to affect you, as they are not immediately obvious from reading the headline specs. Informed decisions and realistic expectations, etc.
Samsung 12kW gen6 ASHP with 50L volumiser and large radiators. 7.2kWp solar (south facing), Tesla PW3 (13.5kW). Net Zero
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