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Nowty Towers Power Station
Main 4kW PV system generated 425 kWh which is 13% below baseline, also has bust the 50MWh milestone in a little under 12 years.
Total PV arrays generated 1113 kWh.

Electric Import was 4 kWh.
Gas import was 34 kWh.
Out of house EV charging was 0 kWh.
Petrol used in EV hybrid was 0 kWh.
Total imported energy use 38 kWh

PV electric export was 113 kWh.
Ripple GF wind farm generated 525 kWh which is 2% below baseline.
Total energy offset 638 kWh

Net energy import for Nowty Towers Minus 600 kWh

2023 (cumulative) Net Energy Import 313 kWh

nowty wrote: ↑Thu Aug 31, 2023 10:55 pm Nowty Towers Power Station
Main 4kW PV system generated 425 kWh which is 13% below baseline, also has bust the 50MWh milestone in a little under 12 years.
Total PV arrays generated 1113 kWh.

Electric Import was 4 kWh.
Gas import was 34 kWh.
Out of house EV charging was 0 kWh.
Petrol used in EV hybrid was 0 kWh.
Total imported energy use 38 kWh

PV electric export was 113 kWh.
Ripple GF wind farm generated 525 kWh which is 2% below baseline.
Total energy offset 638 kWh

Net energy import for Nowty Towers Minus 600 kWh

2023 (cumulative) Net Energy Import 313 kWh

It’ll take less than 12 years to do the next 50MWh!

That's the first full 12 months of solar generation done, quite a few changes to the system and config in that time but it's all running smoothly now.
A pretty mixed month in terms of weather, but generation has been more than enough to cover consumption. Hit 97.4% PV contribution, almost beating May.

Currently at net export of 628kWh for the year, that'll start ticking down this month.

My results for August were:

3.87 kWp, slope 50 degrees, due south, lat 57.15

Total generation: 417kWh

Daily average: 13.5kWh

Generation per kWp: 107.7kWh

Daily average per kWp: 3.5kWh

PVGIS: 342kWh

%PVGIS: 122%

A little late this month. Lost about 30% potential due to Victron system shutting down when batteries full. This was mostly down to the inverter being set to charge for 1.5hours through the night and my not being able to switch it off from Turkey. A software issue on the Goodwe Hybrid inverter.

Solaredge PV 467kWh
Victron PV 357kWh
Ripple Graig Fatha WT 457kWh

Total RE generated 1,281kWh
Bought 270kWh E
Bought 0kWh G

Dan's office solar for August

Generation - 1.21MWh
Self-consumption - 0.74MWh (61%)
Export - 0.47MWh

Grid import - 1.23MWh
Overall consumption 1.98MWh

369kWh this August which is markedly down from the 438kWh for August 2022, good enough though (just) to cover daily usage but it did feel more like a shoulder month with load management being more of a requirement at times.

Moxi

542kWh generated, against PVGIS of 500 - better than I thought, given how wet / grey / miserable it was for most of the month.

Not as good as 579 from last year - this is the first month where I have 2 lots of data, although at this time last year, the battery wasn't working properly due to CT coil issues, so October will be the first month to properly compare savings etc.

It's all looking good, year to date is almost 500kWh ahead of PVGIS

Use

660kWh (expected generation, PVGIS, 6.4kWp system)
501kWh generated (75.9% expected generation)
305.84 kWh imported (320.3kWh@16.92p/5.8kWh@28.2p/1.2kWh@39.48p) = -£56.30
392.11 kWh exported (253.5kWh@30.45p/153.6kWh@18.61p) = £105.76

221.93kWh of gas imported = -£15.71

Standing charge

Electric 31*49.83 = -£15.44
Gas 31*0.2616 = -£8.11

Total
+£25.91

Potential savings
Shifting generation: 153.6kWh could have been sold at higher rate = £18.19

Without putting the calculations in more detail, with a larger battery and the current inverter system I could attempt to arbitrage maybe a further 12kWh per day. Which would be £50 for this month. At PVGIS expected performance: generate £29.78 at middle rate export, if entirely shifted to higher rate, generate £48.72. ie battery would save a further £19.

15kWh is probably the sweet spot for battery size for a house with no electric heating. Beyond that only makes sense for a true off grid lifestyle and redundancy, or to fit a second system with DC charging to get around MCS rules.

That’s some good man maths!

I wonder what sized battery would be the “right” size for my office setup and how I would calculate it? My boss is highly skeptical that a battery could ever be a cost saving measure, unlike the solarPV