Octopus Energy Saving Sessions

[Stranger Dings]

Does anyone know how the Octopus ”Power Hour” energy saving sessions are actually calculated?

I’ve taken part in all of them, but the results just seem totally random.

I’ve had sessions where we’ve switched off as much as we can and gone out, only to be told that we didn’t manage to save anything.

Some sessions, we’ve made very small savings, Including one where virtually everything was switched off and the whole family was in another country.

One session I forgot it was happening despite signing up, only to be told I’d managed to save 93% of my normal usage and be credited with over £16 off!

I’ll continue to sign up for them and don’t really do it expecting to save much as we are already quite energy efficient. It all just seems so random.

 

[Pink Duck]

That’s the case if your meter readings were working at the time of opting in but the data wasn’t available in a timely manner afterwards.

“This Saving Session, 1 random opted-in customer will win 888,888 Octopoints - worth £1,111!

PLUS: Super Saver Bonus – the Top 20% of Savers will bag an extra 400 Octopoints, based on the proportion of energy you save compared to normal.”

 

[Js1977]

In the past when my meter wasn't sending readings I was credited with an average savings from other users ... which was a much better deal than the paltry amount we are able to genuinely save!

When I was on the phone earlier the rep said they would compensate me a couple of quid or so to which i said I normally "save" a bit more than that.

I cant really save energy due to the battery but at least they know the consistency of my export... hopefully.

 

[ringi]

This happened with me when I changed to flux in April last year, my readings were stuffed for months, then the day I move back to go and outgoing it miraculously fixed itself and has worked perfectly since. So it is clearly an octopus system issue that stuffs it up (not that they would ever admit that but it seems pretty clear)

Not necessarily, it could be the meter does a reset when given new tariff data. Or sending an active command to the meter clears a problem on the coms network.

 

[Js1977]

Not necessarily, it could be the meter does a reset when given new tariff data. Or sending an active command to the meter clears a problem on the coms network.

Yes this is also true as per what the rep told me earlier and would make sense with previous disruptions. However, this latest disruption is after it was fixed and I finally got my bill after 3 months. Bill was given on the 3rd of this month and all the data was there then and had been for a few days before... coincidently it also stopped working from then until now

 

[Js1977]

Well, it let me opt in so ill just crack on as usual and hopefully they will get my readings sorted out soon

Result.. All the data is back and up to date and message from the account is now gone... that was quick!

 

[Pink Duck]

With 46.7 GW peak yesterday at 18:00
and 48.0 GW peak today at 17:30
…will they go for another this evening? (seems not as of 10:07)

My own calculations for last night:
17:30–18:00 avg. 9.4164 kWh (import) vs −2.489 kWh (export) = 11.9054 kWh ‘saved’
18:00–18:30 avg. 8.6077 kWh (import) vs −2.488 kWh (export) = 11.0957 kWh ‘saved’

Totalling 23.0011 kWh @ £2.25 = Another 41,801 OctoPoints (presuming top 20% bonus)

 

[thewishy]

Anticipatory notices have typically been issued at 8am, with one "test" at 10am. Given they haven't published a notice, it would seem that the ESO are happy with their margins tonight. Wind does seem to be picking back up a bit, to be fair.

 

[yessuz]

With 46.7 GW peak yesterday at 18:00
and 48.0 GW peak today at 17:30
…will they go for another this evening? (seems not as of 09:16)

My own calculations for last night:
17:30–18:00 avg. 9.4164 kWh (import) vs −2.489 kWh (export) = 11.9054 kWh ‘saved’
18:00–18:30 avg. 8.6077 kWh (import) vs −2.488 kWh (export) = 11.0957 kWh ‘saved’

Totalling 23.0011 kWh @ £2.25 = Another 41,801 OctoPoints (presuming top 20% bonus)

can you clarify on the following:
1) why your import is so high during the peak?
2) what time period is taken for the the avg consumption? last day, three days or so?

 

[phil4]

2) what time period is taken for the the avg consumption? last day, three days or so?

Average of the hour over the past 10 week days excluding any savings sessions.

And yes, I can see why you're asking, 9.4kWh import in half an hour (so drawing 18.8kW for that 30 mins), at that time of day, is pretty impressive, even charging a car or two wouldn't do that. Would need some reasonable use over that.

 

[Pink Duck]

1) why your import is so high during the peak?
2) what time period is taken for the avg consumption? last day, three days or so?

1. Because it is peak grid demand for many and I arrive home shortly after 17:00 to a rather cold property.
2. Averaged over last 10 eligible working days (from 3rd Jan), which is why I suspected first of 2024 was 17th (Scotland 2nd Jan bank holiday)

 

[yessuz]

Average of the hour over the past 10 week days excluding any savings sessions.

And yes, I can see why you're asking, 9.4kWh import in half an hour (so drawing 18.8kW for that 30 mins), at that time of day, is pretty impressive, even charging a car or two wouldn't do that. Would need some reasonable use over that.

heat pump + oven + swimming pool?

 

[yessuz]

1. Because it is peak grid demand for many and I arrive home shortly after 17:00 to a rather cold property.
2. Averaged over last 10 eligible working days (from 3rd Jan), which is why I suspect the first of 2024 was 17th (since Scotland goes back day later)

i understand, probably heat pump?

but isn't it the case, that it makes so much more sense to maintain some sort of 20 C (or whatever) during the day when you are not at home and then bump up if needed once returning rather than to switch off the heating altogether and to turn it on on full blast in order to warm up the house?

I am sure that there's shitloads of articles about this :/

 

[Pink Duck]

Quite a few have experimented with heat pump on all day to target temp and scheduling off. Basically, if you’re not resident much and the property is well insulated it tends to win out to not operate continuously.

My evening Saving Session was around 16.3 °C with hot meal and Thermos hot drinks to LED torch light (and over-ear headphone music).

 

[yessuz]

Quite a few have experimented with heat pump on all day to target temp and scheduling off. Basically, if you’re not resident much and the property is well insulated it tends to win out to not operate continuously.

My evening Saving Session was around 16.3 °C with hot meal and Thermos hot drinks to LED torch light (and over-ear headphone music).

not sure if worth it, really.. maybe yeah...

but my other family members would kill me

 

[KennethS]

not sure if worth it, really.. maybe yeah...

but my other family members would kill me

We keep our house at 19c. My children ceased complaining when I showed them the monthly gas bill and told them they are free to increase the temperature in their rooms and they can take over the bill paying.

 

[yessuz]

We keep our house at 19c. My children ceased complaining when I showed them the monthly gas bill and told them they are free to increase the temperature in their rooms and they can take over the bill paying.

I keep 20. but mine is new build (well.. 2014) and quite well insulated

 

[ACarneiro]

i understand, probably heat pump?

but isn't it the case, that it makes so much more sense to maintain some sort of 20 C (or whatever) during the day when you are not at home and then bump up if needed once returning rather than to switch off the heating altogether and to turn it on on full blast in order to warm up the house?

I am sure that there's shitloads of articles about this :/

From a comfort perspective that makes sense.
From a thermodynamic perspective, heat loss is an exponential process so keeping the house warm all the time just means you lose more heat all the time.
I really, really don't know where this fallacy has come from saying that "it's cheaper to just run it all the time". It's simply not true. It may be more comfortable, but not cheaper.
What is true, however, is that once you crank the heating up again you will have a spike in electric usage and have to wait for a bit until the temperatures stabilise.
I suppose you could argue that it's better for the grid to have a higher but lower intensity draw all dat long than have lower total draw but with a high intensity peak just at "coming home o'clock", but that's a different matter.

 

[thewishy]

I really, really don't know where this fallacy has come from saying that "it's cheaper to just run it all the time". It's simply not true. It may be more comfortable, but not cheaper.

It depends on the system capacity. Clearly it's bollocks if you're talking about gas central heating where you're likely to have a 30kw boiler for a house with 5kw of heatloss - you've got a sledgehammer to crack a nut there, and you won't see substantial changes to efficiency across the burner modulation range (if it even has modulation). You will, maybe, save 10% if you run at a lower flow temp for a longer time on a combi boiler, but that'll get eaten by thermal losses pretty darn quick.

With resistive heating, it's "100% efficient" all of the time, so no argument there either

With a heatpump
1) You don't want to spend thousands extra oversizing the heatpump, so you might not have the ability to rapidly heat the house, especially with UFH which tends to favour "low and slow". So that's a reason to leave it running
2) With longer run times, you can run the flow temps lower and get a higher COP

I don't think for a heatpump you've got an easy rule of thumb, it'll depend on your emitters, how insulated your house is, how much excess capacity you have in the heatpump vs thermal losses, etc. And of course, your own preferences and habits. Eg are you always home when you plan to be

 

[yessuz]

From a comfort perspective that makes sense.
From a thermodynamic perspective, heat loss is an exponential process so keeping the house warm all the time just means you lose more heat all the time.
I really, really don't know where this fallacy has come from saying that "it's cheaper to just run it all the time". It's simply not true. It may be more comfortable, but not cheaper.
What is true, however, is that once you crank the heating up again you will have a spike in electric usage and have to wait for a bit until the temperatures stabilise.
I suppose you could argue that it's better for the grid to have a higher but lower intensity draw all dat long than have lower total draw but with a high intensity peak just at "coming home o'clock", but that's a different matter.

well.. is it though?
I think from Thermodynamics point of view, it takes as much energy to reheat your house as the amount of energy you conserved when the heating was off and temperatures were dropping

But in reality, you warming up not only air in the house, but also all the walls, ceiling, etc. It has a huge thermal mass which you have to reheat.

also I think in the heat pump systems it is more efficient to keep steady temps than have massive deltas. but I can be wrong

 

[ACarneiro]

it takes as much energy to reheat your house as the amount of energy you conserved when the heating was off and temperatures were dropping

True, if you're allowing the house to cool down (as the house gets progressively colder it loses progressively less heat per unit time, assuming the temperature outside stays constant).
Not if the house remains warm. Hence my point that you're better off turning the heating off when youtnobody is there to benefit from it.

Good point about the heat pumps, I hadn't thought of the quirks of their operating modes so I will have to admit ignorance on that front....