export data way off

8 comments started 2025-05-22 last 2025-05-22
GivEnergy ProductsHybrid
M
#1 Marren2016

Hello, going back to the topic of Octopus ripping us off, for monday and Tuesday my GE app say 24kwh exported, octopus are claiming 17kwh, how can it be off by 7kw over 2 days?

Can anyone give me any pointers?

I have a voltage optimiser that is set to 227v on average.

G
#3 geoffreycoan

Marren2016 I don’t know how voltage optimisers affect your import and export data, but this could be related.

227V is on the low side, The UK standard is 230V +10% -6%, maybe increase the VO a bit and see if the difference reduces?

M
#4 Marren2016

geoffreycoan that's probably a good idea.

S
#5 SteveCook

The numbers in post #1 suggest around a 30% discrepancy (depending on which numbers used)
227v verses 230v is about 1.3%.

The smart meter will be reading V and A to do the math and your GE system will be using the EM115 (which is/should be MID approved and will be measuring V and A and doing the math V X A X seconds)

Are you certain the GivEnergy data is correct?
Can you take some manual meter readings over a couple of days - though this will depend on your tariff - possible with Eco7 as there are 2 registers, but probably not on a 1/2 hourly tariff, and compare with your GE readings

#6 hoggy

Depends where your reading it from. The portal is inherently at risk of drift because of how it interprets each 5 min reading (for which it assumes it was doing whatever that 5 min reading was, until the next datapoint)

#7 Windy Miller

The Portal might be displaying the 5 minute aggregate export but the EM115 which contains the counter should be a lot closer. These are displayed on the meter data tab on the Portal under the My inverter page. I might expect 5% discrepancy but not 30%. It could be that they are measurements over different time-frames. It could also be they are not measuring the same thing. Is the EM115 current transformer on the same wire as the one through the smart meter? Is the EM115 on the other side of the Voltage Optimiser from the EM115 itself so it measures voltage one side and current the other?

M
#8 Marren2016

Somehow I got the days mixed up.
Long day at work, hot weather. Octopus are showing more energy exported than GE.

I'm a tard.