So much for the Ofgem 2% price increase. Just got my Octopus Cosy tariff, I am on their lowest tariff.
Standing charge up by 5%, all the other rates up by 15%.
We only have electricity so a smaller increase, or even a reduction, on gas is not reflected in our increase percentage. How are others faring?
IOF rates remain the same but standing charge up 5%
Roy124 I’ve just been looking at the same, I’m currently on Agile but was planning on going to Cosy for the winter.
Cosy day, peak and offpeak rates all up 15% for Eastern region.
Go and Intelligent Go overnight rates remain the same, 1.2% day rate increase for Go, 1.5% day rate increase for iGo.
Not sure how they can provide overnight rates at 7/8.5p when the agile overnight rates are 15-18p, and the EV tariffs don’t have a peak period, but clearly the EV owners are being protected at the cost for everyone else.
I did do some back of envelope crunching to see what tariff would be best for the Dec/Jan/Feb winter based on a similar consumption to last year and the import rate split from Feb last year on Cosy:
Current Cosy rates priced for Dec/Jan/Feb consumption £706
New Cosy rates £810
Go (assuming full overnight battery charge and 20% of other import shifted to overnight) £886
Agile (average rate 22.1p for same period excluding 4-7pm peak which my battery covers) £1014
Not happy about the increase but Cosy still looks like the cheapest.
geoffreycoan EV owners are the demographic every energy company wants - currently EV owners are almost exclusively in the top 20% of earners. That'll change somewhat with PCP but it'll take several years.
Frankly I don't think it'll be long before EV owners charging at home get hit with 20% VAT, same as all the public charging sites. It'd be hugely popular with the demographic (chavs) that Lab/Con/Reform are targeting and something has to be done to replace the £30bn fuel tax/duty.....
Vestas EV owners charging at home get hit with 20% VAT
Yep, that wouldn't suprise me. They are already (IIRC) making changes so that EV chargers have to be able to "talk" to the energy company - ostensibly to ensure that EV charging can be scheduled so as to not overload the grid - but presumably this would also allow the energy companies to identify the EV charge draw and thus could apply a different VAT rate to that draw
CW presumably this would also allow the energy companies to identify the EV charge draw
Octopus already do this - they recently warned people not to charge EVs during a "free electricity session" and said it'd be charged at standard rate if they did.
Frankly it'd be a complete no-brainer for any chancellor - nobody is going to have any sympathy for EV owners given the cost of the cars (remember there's taxpayer handouts to buy them) and the fact even with VAT they'd still be paying a LOT less than ICE users per mile.
I'm on Octopus GO. Standing charge up 3%. Night rate stays same at 8.5p. Day rate up, but don't care as hardly use any.
No idea what will happen in future, and past experience has shown my ability to predict can be unreliable.
[unknown] hmmm I missed octopus saying not to charge the EV during a free session?
I thought it was for IOG have the car connected?
I will have to double check this...
So certainly for IOG they want your EV plugged in.
Vestas can you source something that says otherwise?
You can also get an hour's free charging for your Intelligent device. Here's how:
Plug in: make sure your car or battery is plugged in throughout the session, then let your Intelligent schedule do its thing (no boost charging!)
Your device might not charge during the session, but as long as you’ve plugged in, you’ll bag an hours’ free charging credit!
M_J That's what I meant - don't charge manually during the free period. There's a thread here which has the actual wording but the tl;dr was charge manually during that period and you'll pay the standard rate.
I only mentioned it to show that energy companies can already identify EV charging from normal domestic usage so charging 20% VAT on that usage would be fairly trivial.
Vestas ok thanks for the clarification.
[unknown] I had a heat pump installed in July this year so have yet to experience a winter, we are now completely gasless and I was hoping for slightly lower bills not increased. It's very disappointing with the cozy tariff going up so much compared to other tariffs, perhaps all of the gloomy stories about heat pumps and their running costs were correct?
Robgy definitely much lower in my case over oil. This increase is pretty minor, at least it is on IOG. My electric bill went up by £200 last year after getting the heat pump. Hoping to improve on that this coming year now we know the system a bit better.
[unknown] I have a fairly small array and battery but the effect of this coupled with no gas has been dramatic over the summer. April to August I think was have paid only £22. It has been hard to work it out as Octopus send so many bills in a month. In contrast, with gas we had paid about £400.
I have been paying £132/m and currently have a £300. I have also withdrawn £700 this summer.
Robgy I have a fairly small array and battery but the effect of this coupled with no gas has been dramatic over the summer. April to August I think was have paid only £22. It has been hard to work it out as Octopus send so many bills in a month. In contrast, with gas we had paid about £400.
I have been paying £132/m and currently have a £300. I have also withdrawn £700 this summer.
BTW, Octopus estimate of my annual usage is just 44kW higher than mine.
Just did rough number for us for Cosy or Go. for 12.3kWh daily, all battery or low rate use.
I could afford 2.5kWh of Go standard rates before Cosy is cheaper.
Vestas I do not, in fact, think this will happen.
Vestas Frankly it'd be a complete no-brainer for any chancellor - nobody is going to have any sympathy for EV owners given the cost of the cars (remember there's taxpayer handouts to buy them)
Would this be just before or just after they also charge heat pump owners who got a grant or people who got loft insulation with a grant 20% VAT on their electricity? There's just no precedent for VAT to be stratified based on either the demographic or quid pro quo of owning a particular product. If tax is to be raised it will be done some other way.
browellm EV charge is not for "domestic use" so there's the legal reason for doing it. The 5% rate is only for domestic use. There's similar "stratification" on use of diesel (red diesel for agricultural use) so there's plenty of legal precedent.
We'll see what happens but ultimately there's going to be a £30bn hole in govt income which they currently get from duty and VAT on hydrocarbons related to motorists. Something is going to have to fill it and its going to be taxes on motorists/electricity/mileage.
TJ from Octopus made a couple of statements on Facebook about this yesterday.
“Hi David. Thanks for the question. We—and I specifically—haven’t abandoned our beloved heat pump customers. I say “I” because the pricing decision was ultimately one I made and it’s important that customers know how and why these changes come about.
We reprice Cosy every quarter based on a number of factors including time of year, underlying energy prices, and expected usage patterns. That means there is always some variability in the rate of change from quarter to quarter and vs. the SVT price cap. This quarter is an especially tough one, as the electricity/gas ratio baked into the price cap has now reached its highest level since 2021 (4.19 😭).
The important thing to know is that the average Cosy customer should still save about 5% vs. gas this quarter if they still have a gas meter or about 10% if they’re totally off gas and their meter is gone. As you have PV and a battery, you can likely save even more.
I appreciate you asking about this. It’s never fun to have to put prices up, and it’s even harder to swallow for everyone when gas gets a wider advantage yet again (elec cap went up 2.4% whine gas cap went down 0.7%).
Hope this helps add a bit of context. You’ll still save on Cosy this quarter over gas, and customers who stayed on Cosy all year will see £150-£250 in annual savings.”
The other interesting thing was about a new Cosy product.
“ Hi Cosy fans. I wanted to update everyone on the changes to the Cosy Octopus tariff this quarter.
Unfortunately Ofgem has raised electricity unit costs and reduced gas costs in the latest price cap. With the Cosy tariff, we absorbed some of the implicit supplier cost rise to ensure heat pump still cheaper than gas, but we did still need to raise the unit price overall. The increase feels steeper in part because we kept the prices artificially lower for Cosy customers in the last quarter.
You should still save £150 across 2025 even with this price change in Q4 vs gas heating—or about £250 if you’ve ditched your gas meter. With PV and battery you should save more.
Next week we’ll launch a fixed Cosy so you can lock in at a lower price. Very soon we will offer an Intelligent heat tariff and smart control for our heat pumps, which means we’ll be able to unlock more savings to pass on via a type-of-use tariff.
Believe me, we don’t want to put prices up on Cosy. Ofgem’s baked-in spark spread is now the worst it’s been since 2021. It’s a huge impediment to the energy transition and the UK economy as a whole. We know prices are also just too high across the board and are doing everything we can to fight for better and fairer energy costs. 🐙❤️”
Roy124
Mine's up 18% across the board (Cosy), plus 4% on the standing charge, for an estimated total increase at our usage of 15.4%. Very misleading headline on the email, with the actual info buried on the 2nd page of an attached pdf which you then had to calculate manually. I know no-one likes to be the bearer of bad news, but I'd far rather they were just up front about it.
Vestas
They'll have to make 32A Commando sockets illegal if they go that way....
Vestas Frankly it'd be a complete no-brainer for any chancellor - nobody is going to have any sympathy for EV owners given the cost of the cars
I think used EVs are pretty cheap these days? Comparable to ICE ?
Vestas Octopus already do this - they recently warned people not to charge EVs during a "free electricity session" and said it'd be charged at standard rate if they did.
I had assumed that they wanted to maintain some control over how much power is used: if not enough free electricity is being taken, they can charge more cars ; if more is being taken than they planned for, they can reduce how many cars they charge. Similarly for IOF, I guess.
Vestas EV charge is not for "domestic use" so there's the legal reason for doing it. The 5% rate is only for domestic use.
Except that once V2H catches on, energy put into a car could be discharged for domestic use. (That said, I guess they could measure it on the way back out, and refund the difference.)
Hook Thanks for sharing the post from Octopus about Cosy pricing. He makes some good points but doesn’t address why EV rates have only increased by 1-2% during the day (and no overnight increase) when other rates such as Cosy and Agile have gone up significantly. It still seems to be they are protecting one part of the customer base at the expense of others.
Cosy fixed perhaps interesting, see what it is when it arrives. But if we tariff hop between summer and winter this may not be suitable at all.
It is what it is. I’ve done my number crunching and Cosy remains cheapest for my winter consumption vs Go or Agile. At the moment I’m enjoying the cheap Agile rates due to the wind we are having but will keep an eye on Predbat compare to guide me when to switch to Cosy. Won’t leave it too long like I did last winter.
On the EV point:- It would not be possible to distinguish whether generated or imported power were going into the vehicle. This would lead to litigation when people objected to paying higher rate VAT on domestic imports when using all their solar power to charge the EV.
On the tariff point:- Octopus haven't raised all the tariffs. While our Cosy tariff went up by 14.8%, the Octopus Flux Export tariff has stayed exactly the same. 😉
If only there was an easily administered existing tax that differentiates different types of vehicle which could recover a notional revenue deficit without inventing complicated VAT treatment to domestic electricity use which own its own is a mental concept. Notwithstanding that the second hand EV market is rapidly being flooded with low-cost vehicles, changing the ownership demographic which is always what was going to happen after the early-adaptor phase.
geoffreycoan Are those figures right?
"The important thing to know is that the average Cosy customer should still save about 5% vs. gas this quarter if they still have a gas meter or about 10% if they’re totally off gas and their meter is gone."
So basically they're saying that the heatpump/cosy is going to save 2 x gas standing charge per day? That's not even 60p/day!
Much better (not for the environment) to stay on gas if its available to you given it'll take the average heatpump owner (£6k install) 27.5 YEARS to recover the cost..... assuming of course Octopus are being honest, which isn't a given.
Vestas if your gas boiler is end of life, then you're paying to replace it anyway. So it's only the difference in price you need to make up.
DD Or you replace like with like and save 4-5 grand. Its a spurious argument I'm afraid.
Vestas Our Heat Pump cost maybe £800 more than a replacement boiler which would also have been expected to need replacing within the expected life of the Heat Pump.
We really need to stop this "it'll take X years to payback" nonsense that is only ever mentioned when talking about green technology. It's a FF tactic. Differences in price are only relevant when the replacement is like-for-like.
Heat pumps are superior to gas boilers. They provide higher levels of comfort and don't destroy the atmosphere that we breathe. Those two points alone are of huge value. They fact that we can have these huge advantages for the same or slightly lower price is nothing short of breath-taking.
If you were replacing a kitchen or re-decorating a room you would only concentrate on the advantages and benefits of the new installation over the old. No-one ever mentions the "pay-back" time of a new kitchen. We need to do the same with green tech.
Zakalwe That's a ridiculous take. It's not nonsense at all, there is literally no difference to the comfort level between heat pumps and modern modulating gas boilers, people just run them as on/off as for the majority of the working population, it's utterly ludicrous mathematically to keep the house warm all the time. As for payback, of course it is the most imperative factor as otherwise they'd be absolutely no point in taking out a 1950's open boiler and installing a condensing boiler, the point is people can save money on their bills. If heat pumps are 5x the price of gas boilers (which they are before another tax payer buys it for you), then they would have to be 5x better for it to be a sensible investment by a homeowner. They are not. Before you say I'm anti heat pump, I have both a ground source and air source heat pump.
[unknown]
The theory is very different from the practice though, as most boilers are way over specified and are installed in an on-off control method.
My heatpump didn’t cost 5x as much as a replacement oil boiler. What did cost extra was replacement radiators and hot water tank. We replaced the radiators because they were nearly 30 years old. The tank was replaced so we could have more hot water at a decent pressure. This also free’d up a cupboard. The removal of the oil tank released about 10m2 of garden. All this increased our electric bill by about £200 and reduced the oil bill by £650 (and that was about £350 less than the year before - isn’t loft insulation wonderful!). Obviously this doesn’t apply to everyone but a friend has just got two gas boiler quotes in one at £3k and one at £7k! With no other changes.
As an example, my 5 year old house was fitted with a 18kW gas boiler. Weather compensation fitted but not connected to the boiler. Micro-bore piping to single panel rads. All in a house with a 5kW heat loss.
Al E.Gator before another tax payer buys it for you
The taxpayer also paid for the gas network. Per the 2021 OBR report-
Following the discovery of North Sea gas in 1965, the Government sought to exploit this indigenous fuel supply that was cleaner and more efficient than either coal or ‘reformed’ town gas (which was produced from
imported liquid natural gas) and invested rapidly to convert houses to using natural gas.A huge number of buildings had to be converted. A contemporary study noted that, “the process [of conversion] was particularly arduous […] since it involved converting 13.5 million domestic and 650 thousand commercial and industrial consumers.”c The process took almost precisely 10 years to complete, with Sir Dennis Rooke, Chairman of the British Gas Corporation, claiming it as “perhaps the greatest peacetime operation in this nation’s history” at a ceremony to mark its completion.b
...the conversion to gas heating was still a major
logistical undertaking. Moving 13 million properties to natural gas involved the 12 regional gas boards, parts of industry (to make new appliances or the parts necessary to convert existing ones), contractors (to enter people’s homes and carry out the conversions), public relations (to
sell the idea) and the public (to embrace it).b The Government took a central coordinating role, with a nationalised Gas Council giving the state direct control of the required investment.h
It is worth remembering that British gas industry was public at the time and was not privatised until 1986 when Margaret Thatcher was Prime Minister.
pwdst I remember the changeover (although I was only 12 at the time). North Sea gas had a higher calorific value than the previous town gas, so new burners were fitted to our gas hob which had a much smaller flow rate, which gave the false impression (to me, at least) that they weren't working as well as the old ones. That was luckily the only gas appliance in the house (huge coke-fired boiler in the cellar! - years later replaced by a huge gas boiler)
I think while the debate about best form of heating and associated energy source continues, the real drive should be to "fill the holes" before pouring any energy in. The drive should really to be to fix the UK residential building stock by insulating, insulating and insulating. I appreciate it is easier to install a heat pump in one room as opposed to insulating walls and roofs throughout a house, but the current approach is like saying "Dont bother buying a new plug for the bath ('cos it leaks), just open the taps more"
The OBR report does talk about this and a string of failed attempts to improve insulation through various initiatives - one example was 14,000 people taking up a scheme that had targeted 1.4 million.
The question is if the Government has failed to reach people in fuel poverty with schemes that (IIRC) often offered insulation for free, or if there is some other reason people haven't taken it up.
If you are working three jobs to keep a roof over your head and your children fed, I can easily imagine not having the time to jump through the hoops even if the result would be a warmer house and lower bills. I find it harder to understand why pensioners would not take it up unless it is simply lack of awareness.
My mum is 82 and lives in a semi-detached house on hill road. She is on the lower side of the pair and so most of the house is over an empty void about 3 foot high. The floors are timber and the void is ventilated by air bricks. This must be a huge heat loss path, and the disruption to her of pulling up carpets to get to the cut floorboards (my dad and I did 50 years ago when rewiring) is too much for her to contemplate.
When they bought the house it was heated by coal fires in downstairs rooms and hot water by a coal stove in the kitchen. 1938 house.
My dad and I did lots of loft insulation and filled the cavity walls. We got the single glazed Crittal windows replaced with double glazed UPVC.
Because she owns the house, access to any grants is unlikely and so she does not see much point in spending her money for something that will probably not bring her much benefit. Floor void insulation does not seem to be in the scheme!
British housing stock, as with so much in this place, is a disgrace and decades behind the civilised world.
SteveCook Your mum could be eligible for grants. Have you tried these?:
Vestas In the UK Red Diesel is not for the exclusive use of agricultural vehicles.
As time goes by there will be changes on taxation of many things not just motorists.
Prices are being sent out for a 12 month fixed cosy tariff. Taken from the octopus forum.
Check out the prices here.
https://octopus.energy/octopus-smart-tariffs/fixed-cosy-octopus-rates/
You are tied in for a year with £25 exit fee.
Better to get more solar panels for the winter!!!!
I need a new 50m fence anyway 😂
NormC Thanks for sharing the Cosy fixed link.
For my region (Eastern), standing charge is the same as the new Cosy rates and the off-peak, day and peak unit rates are all 3.94% less than the new Cosy rates. At least it reverses a bit of the 15% price increase.
My estimated £810 Cosy import bill for Dec/Jan/Feb consumption (which is £706 on current Cosy rates) would come down to £778, a £31.91 reduction.
Predicted price cap rates for a typical household:
So if you plan to stick with Cosy long term this looks to be good deal. Even sticking with Cosy for just the winter (as I probably plan to do) means a saving against the October Cosy rates so I’m definitely considering it.
[unknown] This is from the body of the email I received from Octopus.
"The rates are cheaper than our new Cosy Octopus Flexible rates from October 1 — that’s because while our Flexible prices are based on recent historical wholesale costs, when you fix your prices, we’ll go out and buy a year’s worth of energy in advance, and those future costs are about 4% cheaper overall at the moment.
And it’s because we buy that energy in advance, that there’s also an early exit fee should you choose to switch tariff or supplier more than 45 days before the end of your fixed term.
Several customers have also asked why Cosy Octopus Flexible rates are increasing more than a typical home from October 1.
The first factor is gas unit rates. They are falling in October, which means electricity only tariffs like Cosy are more affected than the average dual fuel tariff.
On top of that, we now have a full year’s data of how real—world heat pump owners warm their homes and respond to price signals. And based on that, we need to adjust prices to ensure we’re not selling Cosy Octopus at a loss.
We probably should have made these adjustments earlier in the year, but instead we held prices below cost through spring and summer. Now that we’re heading into winter, we can’t artificially keep them below our cost to supply the energy to your home.
After the October adjustments, we expect Cosy Octopus Flexible to roughly break even on the cost of the electricity to your home.
We are absolutely committed to ensuring warming your home with clean electricity is cheaper than burning fossil fuels, and rewarding early adopters like yourself for your courage — with the new prices factored in, a typical Cosy Octopus Flexible customer will have saved £150 vs gas heating in 2025, and that figure rises to £250 if you’ve ditched gas entirely."
Still doesn't explain the EV tariffs. I think we can all see that on Octopus at least, everybody is subsidising EV users. It would be nice if they told the WHOLE truth, rather than the bits which suit them.
[unknown]
[unknown] No. A neighbour replaced their gas boiler just shy of £3000. Our ASHP was £1750 to us. Our boiler system needed regular pressure top up. We also had to pay £90 for a new solenoid valve (redundant with the ASHP).
Stored hot water is delivered 20 seconds faster as well.
Vestas The Octopus exec on FB said it was because EV load can shifted almost entirely to off-peak hours.
Vestas I take it you don't own an EV? :-) I sometimes think I'd like a hybrid (not the car) between IOG and Cosy but then realise I'd only benefit a few days a year and I have a word with myself.
I just did some rough calculations and I'd be better off staying on Go, I'd have to use 10kWh of peak rate to match how much Cosy would cost entirely off peak.
Rough cost on Cosy would be £5.5/day so I'd have to use hit that amount on Go before it's worth switching.
8.5p to 14p is almost 65% more!
Avenir Which is complete crap as the Agile rates are double that of the EV tariff at the same time.
thevilla Not yet but my wife's car needs replacing so it'll no doubt happen. I just object to Octopus using everyone else to subsidise EV owners while telling lies as to why thats the case.
Vestas over a whole year?
Avenir Pretty much. Unless its very windy overnight & sunny/windy during the day (rare) the Agile rates are double that of the EV tariffs low-rate at the same time, making a mockery of Octopus' explanation regarding off-peak hours.
The rates were somewhat comparable in 2023 but not since then. Agile users have been subsidising EV users since then.
Vestas is it possible that agile is based on very short-term wholesale pricing, whereas for go/IOG they save by buying it much further in advance? Cosy usage is possibly much harder to predict since it depends very much on the temperatures day to day.
DD Its possible but unlikely and even if that were the case then it'd be a 4% difference (or similar) as said above for Cosy, not a 200%+ difference at exactly the same time.
EV tariffs on Octopus are subsidised by all the other tariffs. It really is as simple as that.
Edit - the alternative is that Octopus only have retired EV owners who charge their car once a week 😉
I am too ill at the moment for a detailed Cosy Fixed/Flex comparison but a quick eyeball puts my fixed offer pretty close to the Apr-Jun Cosy Flex.
I have opted for the fix as my big fuel hit is the 1600-1900 tariff for the ASHP.
How are we all modelling this? I’ve had a great year on Next Drive v4, but with ashp potentially on the way, eyeing up the HP tariffs. Don’t think my gen 1 inverter will be good with the Cosy peak though.
[unknown] Don’t think my gen 1 inverter will be good with the Cosy peak though
Why? It is what I have. For ASHP use you need a battery sufficient to carry through the 1600-1900 slot. I have 5.25kW which covers about 50%. We are however home all the time and need warmer rooms.
Roy124 because at peak time on a cold day the house load plus the heat pump would be around 4kw
Avenir Do you have a 9kW heat pump being quoted for installs? It's also worth noting that the heat loss is usually against a reference temperature of minus two or three so if you had a measured heat loss of say 7kW it would be much less than that in normal conditions.
Thus 95%+ of days you might get away with your existing inverter.
If your background load is 500W and you get a 3.5kW Heat Pump that refers to the Heat output and not electrical input so I would expect your usage to be more like 2kW.
pwdst Heat pump would probably be 5kw, which has a peak draw of 2kw, which I think we'd sustain for a period on a -2C evening, based on previous winter's gas usage. This is hypothetical of course! Add the oven and hob in that period and we'd be looking at 4kw for an hour or so in the peak period – again based on previous usage. Days where the temp goes below freezing would be around 10% annually. We have a 9.5kwh battery.
Curious how other folk are modelling it, the level of detail and assumptions made.
Avenir could you boost the temperature 1pm to 4pm, then reduce heating demand during peak? And/or shift cooking outside peak? (Main meal at midday? We've been meaning to switch to that, but old habits die hard.)
[unknown] I was talking about the installation cost, not the gas price.
[unknown] No, I don’t really want my behaviour and comfort to be dictated by the tariff.
[unknown] Pretty much. Unless its very windy overnight & sunny/windy during the day (rare) the Agile rates are double that of the EV tariffs low-rate at the same time, making a mockery of Octopus' explanation regarding off-peak hours.
The rates were somewhat comparable in 2023 but not since then. Agile users have been subsidising EV users since then.
I’m pretty much of the same view as @[deleted] that Agile users are subsidising EV owners electricity. I get that there is some pre-purchasing of electricity on long term contracts for EV overnight charging, and on iGo Octopus can and do shift charging around to manage peaks and troughs of demand, but Agile is almost always double the EV rates and a few pence more than the Cosy rates. In 2023 and the first 3/4 of 2024 this wasn’t the case, so something has changed. Electricity prices have not increased by as much as Agile has.
When I switch the heat pump on sometime next month, I had planned to go to Cosy, but am likely to go to Cosy fixed now. I’ve been on Agile through this summer again and the occasional windy days have been very cheap, but they are occasional. Tonight the Agile peak rate hit 50p, a worrying sign of things to come.
[unknown] Heat pump would probably be 5kw, which has a peak draw of 2kw, which I think we'd sustain for a period on a -2C evening, based on previous winter's gas usage. This is hypothetical of course! Add the oven and hob in that period and we'd be looking at 4kw for an hour or so in the peak period – again based on previous usage. Days where the temp goes below freezing would be around 10% annually. We have a 9.5kwh battery.
Curious how other folk are modelling it, the level of detail and assumptions made.
I think you will just about be OK with a Gen 1 inverter. I have two Gen 1 inverters, one with a 9.5 and one with a 5.2 battery. In November I drilled a hole in my 9.5 battery (see other post), leaving me with just the 5.2 for the winter.
I have a 9kW heat pump so peak draw can be 4 or 5 kW, and was on Agile at the time and so Predbat would choose which cheaper slots to grid import and which to let the battery discharge. Together yes I did have some peak rate grid import when heating, oven and hob were all on, but it wasn’t too awful and through that winter I found the battery would just about cover me for the peak period.
Its not ideal but it is do-able.
Vestas Pretty much. Unless its very windy overnight & sunny/windy during the day (rare) the Agile rates are double that of the EV tariffs low-rate at the same time, making a mockery of Octopus' explanation regarding off-peak hours.
The rates were somewhat comparable in 2023 but not since then. Agile users have been subsidising EV users since then.
I’m pretty much of the same view as @Vestas that Agile users are subsidising EV owners electricity. I get that there is some pre-purchasing of electricity on long term contracts for EV overnight charging, and on iGo Octopus can and do shift charging around to manage peaks and troughs of demand, but Agile is almost always double the EV rates and a few pence more than the Cosy rates. In 2023 and the first 3/4 of 2024 this wasn’t the case, so something has changed. Electricity prices have not increased by as much as Agile has.
When I switch the heat pump on sometime next month, I had planned to go to Cosy, but am likely to go to Cosy fixed now. I’ve been on Agile through this summer again and the occasional windy days have been very cheap, but they are occasional. Tonight the Agile peak rate hit 50p, a worrying sign of things to come.
Avenir Heat pump would probably be 5kw, which has a peak draw of 2kw, which I think we'd sustain for a period on a -2C evening, based on previous winter's gas usage. This is hypothetical of course! Add the oven and hob in that period and we'd be looking at 4kw for an hour or so in the peak period – again based on previous usage. Days where the temp goes below freezing would be around 10% annually. We have a 9.5kwh battery.
Curious how other folk are modelling it, the level of detail and assumptions made.
I think you will just about be OK with a Gen 1 inverter. I have two Gen 1 inverters, one with a 9.5 and one with a 5.2 battery. In November I drilled a hole in my 9.5 battery (see other post), leaving me with just the 5.2 for the winter.
I have a 9kW heat pump so peak draw can be 4 or 5 kW, and was on Agile at the time and so Predbat would choose which cheaper slots to grid import and which to let the battery discharge. Together yes I did have some peak rate grid import when heating, oven and hob were all on, but it wasn’t too awful and through that winter I found the battery would just about cover me for the peak period.
Its not ideal but it is do-able.
geoffreycoan There is of course another explanation for the higher Agile rates - and that's to do with grid trading a la predbat etc 🙂
Apart from windy days Agile pricing does seem to bottom out just below the outgoing "fixed"* rate of 15p - close enough that cycling batteries wouldn't be profitable.
I've always thought it was a bit of an anomaly that you could opt for Agile import but fixed rate export.
Probably just me being cynical 😉
*fixed but they can change it within the contract term now.
NormC On top of that, we now have a full year’s data of how real—world heat pump owners warm their homes and respond to price signals. And based on that, we need to adjust prices to ensure we’re not selling Cosy Octopus at a loss.
This is the key bit to me. Reading between the lines: The dynamic pricing is doings its job too well. Heat pump owners are probably more likely than most to also have battery storage. Like me, they import the vast majority on the low rate (for me 96.9% over the last 12 months according to OctopusWatch, though I was on Agile for the first few months of that, so probably not quite so clear a picture), only a small amount on the standard rate (2.6%) and almost never import on the peak rate (0.5%). This is unsustainable for Octopus, hence the big uplift on this tariff.
I switched to Cosy Fixed. It is lower than the October tariff which is good. It is also slightly lower than the April tariff which, for me, was a net zero quarter. The break point will be the Jan 26 quarter as the previous Jan qtr was lower than Apr.
If the Jan 26 qtr is higher than Oct 25 the fix will be a good thing.
Roy124 If the Jan 26 qtr is higher than Oct 25 the fix will be a good thing.
The predictions https://www.moneysavingexpert.com/utilities/what-is-the-energy-price-cap/
suggest a small 0.5% fall for Q1 2026 then up 7% in Q2
For me with my consumption I think I will get the Cosy fix even if I break it in Spring next year, I’ll still save compared to the standard Cosy