Posted by: @toodles

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As you may remember, I did write to Greg J. a while back suggesting that Solar +Battery + Heat Pump users might be considered as a group worth a special tariff and an assistant replied thanking me for me suggestions and that he would forward the details to the appropriate department. I might go blue in the face meanwhile but one can but hope, for as I pointed out, Heat Pump users might well equate to some EV Car users’ consumption.

Yes, I have not yet done real calcs. But it seems that even basic calcs show that it does not work. 

I called Octopus and outlined the case. I buy at 3.5p with the EV tariff at the moment. Cosy would mean the lowest rates would go to 14p. So a 4x increase. As we can buy gas at 7p, so 14p keeps the heatpump cost below gas.

But for us, all our consumption would cost 4x. So I would give this up for the whole year to get some benefit for the fewer months our heatpump would be relatively busy, I cannot see the numbers stacking up reasonably. 

But I could keep overnight with a similar rate but also get a 14p rate or even a bit above (for like 3 hours in the middle of the day), it would be worth. 

We discussed this before, which is impacting a growing number of heatpump cases. And we know, people that use one renewable technology are much more likely than the average to use others. 

Posted by: @richard24738

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In fact in these milder temperatures I can export to Axle VPP (very lucrative) and export to Agile Outgoing Octopus, admitably only for pennies.

If i could only charge the batteries at very cheap rate in the night on an EV tariff then my batteries would soon run out before the next charging slot. So happy with Cosy as is and probably that demonstrates the varying tariff needs, in my case without an EV or solar but with Heat pump and batteries.

At the moment, I just export at peak and with the "Ormuz effect", I think we get over 20p/kwh (enough to offset the general consumption, even some of the EV), as below. No complicated config involved and it has been working without touching it for months.  

Is Axle VPP working as a "zero hours contract", where they can have the right to use your battery but only pay you on the days that they do?

I did some modelling using our real consumption figures and even with our smaller 13 kWh battery, our winter average rate per kWh was roughly similar to Cosy rates. Having said that, we do have an EV and put in about 150 kWh per month during winter months, so that might tip the balance to Octopus Go. We used about 150 kWh for the EV, around 700 kWh for the heat pump and 300 kWh for other household consumption in January. Of the 700 kWh heat pump electricity consumption, roughly 200 kWh was during off-peak times. From March to October, Go is the hands down winner when compared to Cosy. 

If we had a 27 kWh battery, I guess we could run 95% of our total consumption using off-peak rates and might end up with a 10p per kWh even during January which is the month of maximum consumption at our house.

Posted by: @toodles

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I am too lazy to try the calculations on this - but I suspect that even current peak charges would leave me worse off than Cosy rates allow for.

Posted by: @batpred

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Is Axle VPP working as a "zero hours contract", where they can have the right to use your battery but only pay you on the days that they do?

In effect, yes.  

Having just signed up to Axle as part of the GivEnergy Premium offer, my understanding is that the default mode is that I retain control of the battery except for maybe 6-8 times a month when Axle take it over for between one and two hours.  The deal is a guaranteed £10 a month or £1 per kWh whichever is higher, with no contractual period.

@kevh I’m eager to hear what Elon is going to offer when he starts his UK VPP plans - anyone heard any whispers on this? Toodles.

Posted by: @kevh

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Posted by: @batpred

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Is Axle VPP working as a "zero hours contract", where they can have the right to use your battery but only pay you on the days that they do?

In effect, yes.  

Having just signed up to Axle as part of the GivEnergy Premium offer, my understanding is that the default mode is that I retain control of the battery except for maybe 6-8 times a month when Axle take it over for between one and two hours.  The deal is a guaranteed £10 a month or £1 per kWh whichever is higher, with no contractual period.

I suspect that would not be a difficult decision, if I had the option. From my calculations we are getting £45 a month. Not even considering that the electricity I do not need to buy during the day is being purchased in the early hours.. when nobody wants it.. 

Messing up my simple programming could mean hours of “enjoyment” troubleshooting axle or vpp..

But I genuinely hope it works for the ones blazing that trail!