Renewables: "talking 'bout my generation"

Grandad2b

8kWh, 1.8 O's. Ending the month with 108% PVGIS.

Merlin139

Ended the month on 520 kWh or 130.8 O's

112.2 % of PVGIS

Overall the month rank 6th of 9 but this is the first month where we have beaten 2022. 

227 kWh behind this time last year.

Diverted 143 kWh through i-Boost.

Paid for 54 kWh of Gas and 91 kWh of Electricity.

Magnitio

A relatively poor 2.88 O's for the last day of the month. Good last half of May resulted in 105% of PVGIS, which is 4% better than last May.

Magnitio

Grandad2b said:

I've long suspected my inverter isn't telling me the truth about daily generation and now I think I have evidence: I've taken the data which produces the generation chart and obtained an estimate of the energy output by assuming that the figure stored every 5 minutes is the power output over the whole of the preceding 5 minute interval. I know this isn't true but it's the best I have come up with so far. 
For example, the worst day this month was 12th May. Inverter reported an output of 4.9 kWh. My analysis using the method above gives an output of 3986.7 Wh, a difference of 913.7 Wh. In other words on this day the inverter over-reported by almost 23%. It may balance out; on other days it's under-reported and one day earlier this week when there was only 3 or 4 data points since daybreak I noticed the system was already claiming to have generated 1.7 kWh.
What I think might be happening is that the servers storing the data are based in China and when local time there reaches midnight it saves that day's data meaning that at 5pm a new day begins. I'll be testing this theory over the coming months.

Some of the data from inverters can be confusing as it needs to take into account the losses converting DC to AC. With batteries it gets even more challenging as there are charge/discharge losses as well. If you start a new thread with details of what you are finding and the equipment you use, maybe someone can held/hinder your investigations.

Raxiel

Well, a fine May ended with a whimper. 1.64Os yesterday.

Came close to an entirely negative energy bill this month but these last few days scuppered it. Still a pretty small total, and 478.55kWh generated for the whole month, against 406.79 predicted by PV-GIS puts us at 117%, so can't really complain.

Grandad2b

Magnitio said:

Grandad2b said:

I've long suspected my inverter isn't telling me the truth about daily generation and now I think I have evidence: I've taken the data which produces the generation chart and obtained an estimate of the energy output by assuming that the figure stored every 5 minutes is the power output over the whole of the preceding 5 minute interval. I know this isn't true but it's the best I have come up with so far. 
For example, the worst day this month was 12th May. Inverter reported an output of 4.9 kWh. My analysis using the method above gives an output of 3986.7 Wh, a difference of 913.7 Wh. In other words on this day the inverter over-reported by almost 23%. It may balance out; on other days it's under-reported and one day earlier this week when there was only 3 or 4 data points since daybreak I noticed the system was already claiming to have generated 1.7 kWh.
What I think might be happening is that the servers storing the data are based in China and when local time there reaches midnight it saves that day's data meaning that at 5pm a new day begins. I'll be testing this theory over the coming months.

Some of the data from inverters can be confusing as it needs to take into account the losses converting DC to AC. With batteries it gets even more challenging as there are charge/discharge losses as well. If you start a new thread with details of what you are finding and the equipment you use, maybe someone can held/hinder your investigations.

That's a very good point, and thanks for pointing it out. 
In this case I think I'm justified in taking the power to be output rather than input since the most I have ever seen is 3.6kW which just happens to be the inverter's rated output.
Incidentally at 6:50 this morning I had apparently already generated 1.6kWh for the month which seems a little surprising since the output at that point was just 160W

Martyn1981

May results.

Great month with 120% of target. Small spread, with 117% for the ESE and 125% for the WNW. 

Generated 752kWh (134.77 O's).
Imported 110kWh.
Exported 484kWh.
Total consumption 378kWh. 
Gas was ~110kWh. 

Finally consumption is down to a more reasonable level (including BEV charging). Gen now high enough to allow all PV charging for the BEVs.  A2A units only needed for a bit of heating in the first few days of the month, and no cooling (yet). GCH not used.

Just a small(ish) batt of 4-5kWh, probably would have reduced import to zero)ish), but batts still some time away as the market is so messy.

Second best May generation, beaten only by 2020, with the freakishly high 135% total.

Year end projection of ~6,500kWh of leccy consumption, including BEV's and some space heating from A2A units. Gas projection ~6,000kWh.

KevinG

Pretty good month, third best May behind 2020 and 2016. 20% above PVGIS at 136.15 Os.

ggmf

slightly down on the last couple of days, but still an excellent 6.7 & 3.957 O's

Alnat1

Another completely cloudy day here in South Yorkshire 1.56 O's, tomorrow is promising better.