Octopus Cosy tariff

[Potatoman]

Hi, is anybody on Octopus Cosy tariff without a battery system in-place and if so do you find the running costs are any cheaper than a std rate tariff

[PhilT]

21 minutes ago, Potatoman said:

Hi, is anybody on Octopus Cosy tariff without a battery system in-place and if so do you find the running costs are any cheaper than a std rate tariff

13 hours mid rate tariff = standard rate, 8 hours at half price, 3 hours at 1.5 times, so it's a no brainer, even without a battery or any scheduling.

[JohnMo]

So an average of about 18p kWh?

 

My E7 works out at at 25p so don't go there without a battery or time shift heating.

 

Many tariffs out there you just need to calculate the best average for you.  If you come home and have the oven on for two hours and electric hob on all during the expensive period you need to consider this also.

[mk1_man]

I have been using Cosy (with batteries) and it has been great.  However now looking to move over to Tomato Lifestyle.  They offer midnight to 6am at 5p and then 9:30 - 11:30 at 14p also 22:00 - 23:59 at 14p, rest of the time at 23p and none of the expensive period between 16:00 and 19:00. Bonus is that the standing charge is only 44p    Even without batteries this would be far cheaper than any standard tariff and if you did your hot water run in the early hours at 5p and possibly increased the temperature during this period also it could work really well.   With batteries its a no brainer 🙂

 

[PhilT]

1 hour ago, JohnMo said:

So an average of about 18p kWh?

 

My E7 works out at at 25p so don't go there without a battery or time shift heating.

 

Many tariffs out there you just need to calculate the best average for you.  If you come home and have the oven on for two hours and electric hob on all during the expensive period you need to consider this also.

true but the question was "do you find the running costs are any cheaper than a std rate tariff"

[PhilT]

2 hours ago, JohnMo said:

So an average of about 18p kWh?

 

My E7 works out at at 25p so don't go there without a battery or time shift heating.

 

Many tariffs out there you just need to calculate the best average for you.  If you come home and have the oven on for two hours and electric hob on all during the expensive period you need to consider this also.

sorry I think I misunderstood what you said there, you mean your E7 at the same 13/8/3 ratio of std/cheap/expensive hours works out at 25p?

[JohnMo]

32 minutes ago, PhilT said:

you mean your E7 at the same 13/8/3 ratio

E7 ratio would be 7/14, cheap/expensive.

[PhilT]

21 minutes ago, JohnMo said:

E7 ratio would be 7/14, cheap/expensive.

Oh yeah sorry brain's gone walkabouts today, I'm putting it down to the servere distraction caused by COP29 and Milliband heat pump targets and boiler tax!

[Andehh]

3 hours ago, mk1_man said:

I have been using Cosy (with batteries) and it has been great.  However now looking to move over to Tomato Lifestyle.  They offer midnight to 6am at 5p and then 9:30 - 11:30 at 14p also 22:00 - 23:59 at 14p, rest of the time at 23p and none of the expensive period between 16:00 and 19:00. Bonus is that the standing charge is only 44p    Even without batteries this would be far cheaper than any standard tariff and if you did your hot water run in the early hours at 5p and possibly increased the temperature during this period also it could work really well.   With batteries its a no brainer 🙂

 

That's really interesting, and could well be cheaper then octopus for ASHP usage... Esp in the winter!

[JohnMo]

24 minutes ago, PhilT said:

COP29 and Milliband heat pump targets and boiler tax!

Perhaps a new thread, may be interesting

[DOIGAN]

On 22/11/2024 at 12:00, mk1_man said:

I have been using Cosy (with batteries) and it has been great.  However now looking to move over to Tomato Lifestyle.  They offer midnight to 6am at 5p and then 9:30 - 11:30 at 14p also 22:00 - 23:59 at 14p, rest of the time at 23p and none of the expensive period between 16:00 and 19:00. Bonus is that the standing charge is only 44p    Even without batteries this would be far cheaper than any standard tariff and if you did your hot water run in the early hours at 5p and possibly increased the temperature during this period also it could work really well.   With batteries its a no brainer 🙂

 

Just looking at Tomatoes website, looks like the Lifestyle is only from 1-6 now @ 5p, I am currently on Octopus Intelligent Go, have solar and 14kw of battery storage, is their any limits on Tomato? what is the customer service like? Octopus is great 

[Thorfun]

Doesn’t look like Tomatoes offer an export tariff. I averaged 16.2p/kWh this month on Cosy and still managed to export £9 worth of PV. 
 

can’t see myself leaving Cosy unless something really good comes along. 

[SteamyTea]

When working out the price of ToU tariffs, you cannot just add up the difference rates and divide by the number of rates.

You need to use a weighted average as the consumption in each time slot becomes very important.

[Thorfun]

10 minutes ago, SteamyTea said:

When working out the price of ToU tariffs, you cannot just add up the difference rates and divide by the number of rates.

You need to use a weighted average as the consumption in each time slot becomes very important.

Octopus tells me my usage daily in kWh and £. So I divided one by the other to get my average price per kWh. 
 

then I can calculate how much my usage would cost on a standard tariff and calculate the difference. 

[SteamyTea]

52 minutes ago, Thorfun said:

Octopus tells me my usage daily in kWh and £. So I divided one by the other to get my average price per kWh. 

Taking a standard rate of 20p/kWh and a simple E7 of 30p and 12p/kWh

If you use 15 kWh/day then:

 

15 kWh x £0.2 = £3

15 kWh x ((£0.3 + £0.12)/2) = £3.15

But if 2/3^rd is in the cheap rate, and that should be easy to achieve, then:

(5 kWh x £0.3) + (10 kWh x £0.12) = £2.7

 

Now you have to put your own numbers in, which you should be able to get from a Smart meter as most do half our sampling.

Or create some scenarios in a spreadsheet and shake the numbers out.

 

[FarmerN]

2 hours ago, DOIGAN said:

Just looking at Tomatoes website, looks like the Lifestyle is only from 1-6 now @ 5p, I am currently on Octopus Intelligent Go, have solar and 14kw of battery storage, is their any limits on Tomato? what is the customer service like? Octopus is great 

Still shows Midnight untill 6 IF you have an EV,but only 5 Hours at bottom rate without EV, in my quote.

Really anoys me better rate if I say I have an EV.

I have a charger but no EV , an EV charges here about once a month. Just don't want to basically lie, to get on best tariff.

[PhilT]

33 minutes ago, SteamyTea said:

which you should be able to get from a Smart meter as most do half our sampling.

 

Can anyone actually see the accumulated hours by ToU on their smart meter or in home display. I can't see that for Cosy but possibly you can for E7?

[SteamyTea]

1 minute ago, PhilT said:

Can anyone actually see the accumulated hours by ToU on their smart meter or in home display. I can't see that for Cosy but possibly you can for E7?

I think I can (EDF).

I usually download the daily files (usage and price) then spreadsheet them.

[Russdl]

1 hour ago, FarmerN said:

Just don't want to basically lie, to get on best tariff.

It wouldn’t be the crime of the century.

[Adrian Walker]

48 minutes ago, Russdl said:

It wouldn’t be the crime of the century.

That’s a great album by Supertramp

 

[SteamyTea]

24 minutes ago, Adrian Walker said:

Supertramp

I was at school with Roger Hodgson's little brother.

Roger used to pick him on in his Jaaaag.

[Thorfun]

4 hours ago, SteamyTea said:

Taking a standard rate of 20p/kWh and a simple E7 of 30p and 12p/kWh

If you use 15 kWh/day then:

 

15 kWh x £0.2 = £3

15 kWh x ((£0.3 + £0.12)/2) = £3.15

But if 2/3^rd is in the cheap rate, and that should be easy to achieve, then:

(5 kWh x £0.3) + (10 kWh x £0.12) = £2.7

 

Now you have to put your own numbers in, which you should be able to get from a Smart meter as most do half our sampling.

Or create some scenarios in a spreadsheet and shake the numbers out.

 

sounds way to complicated to me. I'm not going to change my usage to fit in with different rates. if utilising cheap rate to charge my batteries reduces my daily cost then I'm happy to just calculate what I save by doing so.

 

e.g. yesterday I used 52.48kWh and that cost me £9.37.

 

if I select a simple fixed tariff on EDF for comparison at 21.98p/kWh then yesterday I saved £2.16.

 

plus I got 15p/kWh for energy exported which earned me £1.15

 

so, in reality, I paid £0.1566p/kWh. 

[ringi]

On 22/11/2024 at 11:03, PhilT said:

13 hours mid rate tariff = standard rate, 8 hours at half price, 3 hours at 1.5 times, so it's a no brainer, even without a battery or any scheduling.

 

Provided you don't use much more electricity per hour at superpeak times then rest of day.  A 1c reduction in target temperature at superpeak with 1c increase the hour before and hot water timed to cheap rate should do it.

 

Unless you have a EV or large home battery,  then the higher overnight cost then Octopus IO needs considering.

 

But if just heatpump, OVO simple option of a lower rate for all electricity used by heatpump regardless of time of day may be best.