Free Energy Wed 21/8 (13:00-14:00)

[Bam Bam]

I don't actually know which tariffs are included in the offer, only that if you get the email you're eligible. If they're only offering it to people with export tariffs, that's pretty naughty. I did wonder about it being worth it if you're on a feed-in tariff, but I don't know if Octopus even offer such a tariff, let alone whether they've extended the offer to these customers (if they exist).

The half price car charging was worth doing, because my car was literally on 5% at the time, and it was a night-time effort so no solar to lose. I rammed as much as possible into the battery but I think I only saved about £1.85. People with bigger batteries would be able to get more of course, but many people wouldn't have come home almost on their last electron the day before, as I did, so wouldn't have room for so much. But it was a genuine offer.

The mid-day one is very much a two-edged sword if you have significant solar generation, and needs careful calculation as to whether it's really worth it taking into account the export payment that you're foregoing by taking part.

Maybe I need to think about this some more, but as far as I can tell Octopus compares your usage to your average usage during that time. So if you usually export then your usage will be -4 or whatever. So if you usage is then +4 then the difference will be 8.

Don't tell Octopus but I was planning to top-up the car tomorrow lunchtime anyway because I do it when the carbon intensity is low. They will just be giving it us for free instead of us having to pay £1.40.

I'm a very happy customer anyway!

It's not a coincidence that Octopus are doing this on very sunny days. They can read the forecast too. They know they'll have more solar than they know what to do with, so they're trying to get rid of it. If people who have solar export tariffs join in the party, so much the better, that's some solar they're not going to have to pay for. But if you have solar with an export tariff, think long and hard before you get into this one.

Last time I did the running around during the hour, and I made only a few pennies.

Yep, that's it exactly - surplus of solar.

And there is only going to be more of these surpluses as we have more and more solar each year.

It is just like the winter demand scheme but in reverse.

EVs are great for absorbing this surplus, as are electric hot water heaters.

I think it will benefit those with solar export if this surplus gets used up. Otherwise they will cancel/drop export payments sooner!

 

[Rolfe]

Maybe I need to think about this some more, but as far as I can tell Octopus compares your usage to your average usage during that time. So if you usually export then your usage will be -4 or whatever. So if you usage is then +4 then the difference will be 8.

Don't tell Octopus but I was planning to top-up the car tomorrow lunchtime anyway because I do it when the carbon intensity is low. They will just be giving it us for free instead of us having to pay £1.40.

I'm a very happy customer anyway!

This is not something I am prepared to bet the farm on. If I get a credit for everything I used during the magic hour last time, including using my own solar, then I'll reconsider. But even so, they pick exceptionally sunny days, and even if they look at an average usage, that will include a lot of rainy days so how do you know where you stand?

You're fine, no export tariff to lose. Fill your boots, just as I did when they had the half-price charging last Monday.

Yep, that's it exactly - surplus of solar.

And there is only going to be more of these surpluses as we have more and more solar each year.

It is just like the winter demand scheme but in reverse.

EVs are great for absorbing this surplus, as are electric hot water heaters.

I think it will benefit those with solar export if this surplus gets used up. Otherwise they will cancel/drop export payments sooner!

I hope they manage a sensible arrangement. But if they want me to participate in this game they have to tell me that they will credit me with the solar I would otherwise have exported as well as what I actually drew from the grid. And I would want to know in advance how that was going to be calculated, because talking about averages and then running the scheme on days when the sun is splitting the sky is very vague. The email doesn't give much detail at all.

I might email for clarification, after tomorrow's jamboree has passed.

 

[Bam Bam]

I hope they manage a sensible arrangement. But if they want me to participate in this game they have to tell me that they will credit me with the solar I would otherwise have exported as well as what I actually drew from the grid. And I would want to know in advance how that was going to be calculated, because talking about averages and then running the scheme on days when the sun is splitting the sky is very vague. The email doesn't give much detail at all.

I might email for clarification, after tomorrow's jamboree has passed.

Yeah, I'd be interested for clarity on how they calculate this.

 

[Rolfe]

The thing is, import and export are separate. John is intending to transfer to Tomato for his import but to continue to send his export to Octopus. Supposing someone was doing the opposite? Using Octopus for his import but exporting elsewhere. He'd lose that export, for sure. So Octopus really needs to reassure people who have both import and export accounts with them that they will be credited in some way for the export that didn't happen because of their little game. Until that happens, I'm assuming they will not.

Current plan is to ignore tomorrow's jamboree, then email "Pete" and tell him why, and ask what earthly good is this offer supposed to be for people with export tariffs on a sunny day.

 

[Rolfe]

This is fairly typical for the way our weather forecast goes as it gets nearer the actual time.

Still not playing though. My panels have been generating over 5 kw since about ten, and I'm currently exporting 4.78 kw. That is likely to continue.

I also note that I have had no credit for the hour I spent running around on 18th August. I have had a credit for the half-price car charging last Monday, although it was less than I expected. So it looks as it it was all for nothing - or rather, for a loss as I'll be charged for the peak-rate electricity I used. So I have no way to tell if the solar would have been taken into account. I still suspect not.

 

[Bam Bam]

I also note that I have had no credit for the hour I spent running around on 18th August. I have had a credit for the half-price car charging last Monday, although it was less than I expected. So it looks as it it was all for nothing - or rather, for a loss as I'll be charged for the peak-rate electricity I used. So I have no way to tell if the solar would have been taken into account. I still suspect not.

I haven't either. Only had the results for the first session on the 15th. Got £1.01.

Looking at the email it says:

• You used 5.03kWh overall during the Free Electricity Session
• Based on your meter data from the previous few weeks, you normally use 0.04kWh at this time

 

[Rolfe]

I got no credit at all for 18th August. I used 5.92 units of mains electricity during the hour and usually use none. So should I have got £1.19 if they had actually paid me? (That's pro rata for what you got.) I think I was charged £1.36 for the energy I actually used from the mains during the hour. That would have been a loss of 17p on top of the loss of 47p in solar export credit. No, that can't be right.

I have emailed "Pete" so we'll see if I get a reply.

 

[Bam Bam]

I got no credit at all for 18th August. I used 5.92 units of mains electricity during the hour and usually use none. So should I have got £1.19 if they had actually paid me? (That's pro rata for what you got.) I think I was charged £1.36 for the energy I actually used from the mains during the hour. That would have been a loss of 17p on top of the loss of 47p in solar export credit. No, that can't be right.

I have emailed "Pete" so we'll see if I get a reply.

I assume they haven't calculated that session yet as I haven't had my results.

 

[Rolfe]

Might be that.

I am currently reclining on a sunbed finishing lunch, watching the sun glaring down from a clear sky.

My panels are currently exporting 4.79 kw and seem set to keep that up for the entire hour. Definitely not biting.

The hour is past and there was a slight reduction due to a wisp of cloud about 1.40, then another reduction of less than five minutes at around 1.50, so I won't have made the potential 4.7 kwh but it won't be far off it. No way was it worth the effort of gobbling all that up and losing the export credit, just in the hope of using a few kwh on top that would be free.

News just in. The GivEnergy app thinks I sent 4.45 kwh to the grid during the magic hour. (The hour from 12..30 to 1.30 managed 4.78 kwh which must be the maximum possible.) Yes I could have overtopped that with the car charger, but due to the differential between export and off-peak import tariffs, the extra free electricity still wouldn't have made up for the lost export credit.

 

[Rolfe]

Let's go with the 4.45 kwh because that's what actually happened. That's 65.75p export credit. That would buy 9.54 kwh at off-peak prices. So if I'd plugged in, I would have had to use 9.54 kwh to have been in a credit position of any sort at the end of the hour. Suppose I'd actually managed that, each kwh above that is going to net me a saving of a whopping 7p, because everything I use is at the off-peak rate. If, by a superhuman effort, I had managed to shift a whole 10 kwh from overnight usage to the magic hour, I'd have made the princely sum of 3.2p.

I don't think it's even possible, let alone worth it.

If it should ever happen that a big black thundercloud came and hovered over my house for the hour in question, I'd turn on the car charger and the water heater, and anything else I was going to use anyway. But beyond that, even with the solar out of the equation, it's a lot of effort for marginal gains.

 

[Rolfe]

Unless………. You have a Tesla Wall2 house battery! You can then be charging the house battery (5KW); the Car (7KW); Immersion heater (3.5KW) Dishwasher and Washing Machine (up to 5KW variably); (Oven (3KW) and a few other appliances, rendering the few KW of Solar as rather insignificant! It’s not a how to, just what worked for me on this 1hr free Electric with Octopus.

I should perhaps refer to this post, from someone who seems to have made it work.

• Car charger. That's a given, and likely to be the biggest contribution.
• House battery. He must have a different setup from me, because my battery always charges on any available solar and on a sunny day it will be at 100% when the magic hour begins. I could discharge the battery as export to make room, but that would have to be done immediately before the hour started. As I was already exporting the maximum my G99 allows in the hour before the magic hour, as far as I know that export would have been uncredited, so no benefit.
• Immersion heater. Fine if the water is cool when you start, as mine was by coincidence on the 18th, but unless you've deliberately let it cool then the heater will run for a lot less than an hour before it cuts out.
• Dishwasher. I could have done that today, but I ran it last night for preference. I note that both its peaks of power draw were contained within an hour, but both were quite short and most of the time it wasn't drawing much.
• Washing machine. I didn't have any washing I needed to do today. In addition, the washing machine also only draws power intermittently, so reducing the gain, and its final spurt is likely to happen after the magic hour has ended, thus gobbling even more solar export.
• Oven. I don't usually cook at lunch time, and certainly not on blazing hot days. Once again, an oven only draws maximum power for a short time when it's switched on, using a lot less to hold its temperature, so reducing the gain. But mainly, I'm not cooking on a day like today just to save buttons.
• A few other appliances. What is the poster actually doing during this time, to use other appliances that consume a significant amount of energy? Vacuuming? Power tools? More cooking? (I'm thinking microwave, kettle, toaster, bread maker etc.) Sounds like a lot of work. I'd rather lie in the sun.

I'd like to see some details on this. How much solar was generated that didn't get paid for at 15p? How much electricity was used during the hour in total? If we price the latter at 7p, by how much did that total exceed the amount of lost solar credit? Was that credit actually worth all the preparation (cold water tank, house battery discharged, food ready to go in the oven, washing machine and dishwasher loaded and ready to go etc.) and all the running around with vacuum cleaners and power tools?

I preferred lying in the sun.

I'm not disputing that this poster came out in credit. If the thing with the powerwall worked then I think inevitably he would. Car and house battery both charging at once, drawing 12 kw for the entire hour, gets high enough to offset any solar export loss unless you have a humungous solar array and it's very sunny. So you might as well do anything else you were going to do anyway. What I do wonder though is the magnitude of the profit, and whether other gains above the obvious easy ones of charge two batteries and heat some water were actually worth all the effort.

 

[DaevM]

Wow, that's comprehensive ??.

I've got a different tariff which I'm paid based on 50% of what I generate regardless. It doesn't matter what I do, I could use 100% or 0, I get paid the same whether I export it or use it. As you say though, an hour = pence so not really worth the effort.
Also I've noticed I've taken part in 3 and been paid for two. The third was 9 days ago, plenty of time for them to have paid the third, although they do state upto 14 days. The worry about this is not so much having not been paid but if it isn't included as a freebie in my bill and charged at peak rate!! - we will see.

In the meantime, as I stated previously, I think it is more about them testing ways for the grid to accommodate renewables, which are generated on/off, rather than the ramp up/ ramp down of traditional generators. We allow them to effectively create a buffer and protect the grid, which wasn't designed for off on. Unfortunately, during renewables productive periods we're all full from our own solar generation anyway and can't provide any buffer space!

.... and, as is always the way with 'these things', the 3rd payment arrived in my account on Saturday, shortly after I'd mailed them to ask where it was. Very efficient ??.
I will be participating in future to help them out ??

 

[Rolfe]

I haven't had anything other than the half price charging credit.

If you have no solar or you're on a feed-in tariff it can obviously work. Even on a day like today, when my solar is barely covering the house load a lot of the time. But let's face it, they're only going to do this on sunny days, and for people with an export tariff it's extremely unlikely they'll be able to turn a profit. At best you'll gain pence of credit for running around like a blue-arsed fly for a couple of hours.

 

[Bam Bam]

I can't see anyone else's posts at the moment for some reason.

Perhaps I can still post, though, in which case I thought I would share this summary email I got from Octopus.

We did less well on the 21st because my wife plugged the car in but couldn't get force it to charge (turned out she needed to update the givenergy app). I was abroad and started the charge remotely when I noticed her message 10 minutes in to the session.

 

[DaevM]

Wow, that's interesting, never seen that before. Posts there but no content. ?

 

[Rolfe]

It's the weirdest thing. You can see your own posts if you click on "Edit", and as a moderator I can see all the posts by clicking on "Edit", it's just that nothing is appearing in the actual field where the post should be displayed.

 

[Rolfe]

Whoopee, I think we're back!

 

[DaevM]

Whoopee, I think we're back!

Yup - welcome back ??

 

[Bam Bam]

I can't see anyone else's posts at the moment for some reason.

Perhaps I can still post, though, in which case I thought I would share this summary email I got from Octopus.

View attachment 29905

We did less well on the 21st because my wife plugged the car in but couldn't get force it to charge (turned out she needed to update the givenergy app). I was abroad and started the charge remotely when I noticed her message 10 minutes in to the session.

One weird thing is that those figures don't add up to £4.29!

But I guess they had already told me about a £1.01 session, so that makes sense.

70 or so miles worth of free electricity (though some of it was actually for bread making and laundry & dishwashing)- not to be sniffed at!

 

[Rolfe]

I never got anything. Two emails about it have not had any response. Chalk it up to experience.