My mid August figure according to Ovo is 8.76%. My figure, which includes Monday’s consumption, is 6.74%.

I’ve double-checked the figures on the website with those I’ve put into a spreadsheet, and found and corrected a few typos to get to this figure.

There was a smaller discrepancy last month,

Are you missing out weekends by any chance? They now count too!

Yes, I’m including weekend consumption in my calculation of the denominator, but as there are no peak hours at the weekend, there is no contribution to the numerator.

I'm having a bad month according to OVO. "Your average use during peak times is 19.73%". 

But total kWh of electricity this month to date is 5.2, so not a lot of usage to vary. With solar panels charging batteries big enough for a day's use I never understood the variations in %  at peak times. It looks like something went wrong on 11th as it has a spike of usage at around 6pm and then back to zero the rest of the evening. Very odd as the battery was above 90% charge at that time.

I blame the gremlins. 

Your calculations won’t necessarily always coincide with OVO’s, because the data available to you may not be exactly the same as the PM people receive. There are a couple of constraints: 

• There must be 48 half-hour figures for each day. If a single one is missing, the entire day is discarded.
• The usage data must have been received before a cut-off time. This used to be 13:00 the following day, but there was talk of delaying it a bit further. You can’t really know when your own figures were retrieved, so there may be days discarded for this reason.

You can check your own calculations by using @Tron Burgundy’s excellent little bookmarklet: GitHub - Tron-Burgundy/Ovo-Power-Move-Calculator. This collects the underlying data from your account, so it has 3-decimal precision. Sadly, it can’t allow for the ‘delay in arrival of the incoming data’, so it won’t necessarily match the official results precisely.

Can I just check I’ve understood this correctly - are you saying that if they don’t receive just one of the half hour figures for an entire day (eg a weekend that all counts as off-peak) or if they don’t receive that data by a cut-off time the day after then they wont use any of that days data when reporting the percentage peak/total, even if they have received the data by the end of the month?!

I’ve been monitoring what I’m expecting the percentage to be compared to what OVO say, and also was surprised by how incorrect it was in the mid-month email I received today.  It’s useful to hear I wasn’t the only person surprised by this, but it is worrying how incorrect it is.

I know that they’re not terribly attentive to making sure their calculations are correct, so I’m not entirely surprised by this..  With the power move flex they initially calculated the power moves based on UTC/GMT time, and I believe this affected far more people than just me! It was hard work convincing them that there was a problem with their calculations, but I got there eventually.  They’ve definitely fixed this in their more recent power move flex calculations, and claimed they’ve recalculated the figures for all those affected in the early weeks, but I am a little sceptical!

If it’s true that they ignore whole days, even when the data is available, then it makes nonsense of the whole process.  Why are we bothering?

Good question. In my case, not for the chance of a few quid off my monthly energy bill in comparison with the time spent monitoring the figures.

Disregarding a day because of one missing half-hour’s data seems reasonable to me. There are any number of reasons why one or more data packets might not be stored or retrieved, and consequently no way of knowing how much energy wasn’t recorded. If I were to take a 30-minute electric shower, that could amount to more than 5 kWh, which would make a great difference to the day’s Power Move outcome. Since there’s no way of knowing whether it would increase or decrease the month’s percentage result, it’s logical to exclude the day altogether from the calculations.

Disregarding a day’s figures because the usage data were delayed seems also quite reasonable to me. The alternative is to wait until after the end of the month to calculate everyone’s results, which would take a long time and a lot of processing power, and would rule out the possibility of giving progress reports during the month. The daily cut-off time is quite arbitrary, so someone has to decide where it should be. 

Every game has rules, and you have the choice of either playing according to them or not playing at all - it’s up to you. However, any attempt you do make to move consumption out of the peak period will do a little bit towards making our electricity greener, e.g. flattening out the hump you see here (last Tuesday’s use of fossil fuels - gas ■ and coal ■ - to generate electricity in Britain):
  

I would agree under the old rules, when only weekdays were considered.  If one day wasn’t available, then removing it made little difference to the overall figure.  But now that off-peak weekends are included, the challenge percentages targets have been reduced accordingly.  If a weekend day is then ignored it skews everything. 

Hi @Fern3,

I’m going to check with the team to see if there’s a way for you to get a full breakdown of their calculations. I’ll be back once I get a response from the team.

Sure, if a discarded day isn’t a weekday, the omission will have a slightly bigger impact than if it were. That’s the luck of the draw, I’m afraid, and I can’t really see any way around it. Even if a whole weekend day were missing from the final calculation, though, there would still be more than 96% of the offpeak hours to count.

I suspect that the number of instances of a missing weekend-day causing the customer to miss the target is vanishingly small in the overall picture. Do you think this is what happened to you?

Hi @Fern3,

The team have got back to me and said:

“They should be able to take their usage from the data they can see in their accounts and follow step 6 on the FAQ here:https://www.ovoenergy.com/power-move-faqs”

We’re going to reach out to get some account details from you to pass over to the team so they can look into this further. Look out for a private message here soon: https://forum.ovoenergy.com/inbox/overview