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How much am I ‘saving’?
@tim441 Indeed, so many variables! At present, I export solar energy and am paid 15 pence per KWh but I don’t feel it worthwhile to grid-charge the battery at 13 point summat pence, allow ~10% loses for AC-DC-AC conversion to export again at 15 pence; there is no real value in that candle! (We are on Cosy tariff) Regards, Toodles.
Toodles, heats his home with cold draughts and cooks food with magnets.
@toodles agreed... probably worth effort at sub 10p?
IOG is 7p+ vat overnight. Other benefit is ensuring I maximise pv solar prod via exports - not using myself or filling batteries .. say mid May to mid Oct
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
We are currently generating and consuming roughly 7000kWh per year, net exporting for the 6 months April to Sept, and net importing October through to March. We have an ASHP, no EV, 7.2kWp solar and a 13.5kW battery.
Predicted generation/consumption:
Net export 2675kWh during summer on IOF at an average of ~26p per kWh = £695
Net import ~2070kWh during winter on Cosy (assuming we self consume all solar generation) at ~13p = £269
Our SC is 365 x 47.53p = £173.50
£695 export - £269 import - £173.50 SC = £252.50 predicted credit for the year
So we are predicted to be running a positive balance of around £250/year giving scope to crank the heating up a little if it gets very cold this winter. That £252.50 could buy us another 1942kWh of heat in winter, giving me confidence that we can probably crank the thermostat up to 20C having run at a miserly 19-19.5C last winter, or maybe turn the DHW up by a couple of degrees. I've already increased our predicted usage a little as I accept we ran on bare minimum during our first winter as we didn't know where the costs/usage would be. I'm not looking to make a profit, if we are net zero cost I'm very happy.
Samsung 12kW gen6 ASHP with 50L volumiser and large radiators. 7.2kWp solar (south facing), Tesla PW3 (13.5kW). Net Zero
@old_scientist like for like comparisons are almost impossible...
My estimates do not include SC.
Other factors:
We work from home and heat main rooms to 21 deg
Secondary rooms and bedrooms much cooler
Half building is very old & inefficient. Half is modern and well insulated. We mostly heat the newer part to 21 deg plus kitchen in old.
SW England,.. Somerset .. probably milder than some.
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
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