Octopus Energy - is it worth trading energy?

OmegaA

It seems I am missing the point as I feel it is not worth trading energy with Octopus Energy:
1. Flux tariff: 2:00-5:00 buy 14.77p, sell 4.68p; 5:00-16:00 buy 24.62p, sell 13.13p; 16:00-19:00 buy 34.46p, sell 26.21p; 19:00-2:00 buy 24.62p, sell 13.13p

2. So, I charge during the day on solar and the battery discharges 100% between 16:00 and 19:00, so then I have to buy energy back
3. I assume the price is kWh, so I sell for 26.21p and buy back for 24.62p, or earn mere circa 1.5p per kWh. And , since Tesla Powerwall 2 battery is 13.5 kWh, I earn only 20p per day at best (one cycle or charge and discharge), or about £70 a year, or £700 within 10 years, but in reality significantly less
I suspect having less deep charge-discharge cycles will extend the life of the battery, so it is not worth trading electricity. Also, I find that I use a lot of electricity starting from about 18:00
it looks like trading energy is not worth it
Do you think my calculations are incorrect?
Thank you

matt_drummer

It's worse than you think!

You take no account of charging and discharging losses.

You operate your batteries like many other people but not like me.

I do not charge cheaply to discharge for a profit even though I could.

It increases the cycles on the batteries, you make very little if anything and it really goes against what I think batteries are for.

I use mine to store energy for use later, either from solar or importing at the cheapest times of the tariff I am on.

I do not see batteries as an income source, rather a way of reducing expenditure.

My solar panels, I regard as source of free electricity that I either use immediately or store in the batteries for use later.

Anything I get paid for exporting, which is quite a lot actually, is used to pay for what I charge my batteries with when the solar generation isn't enough to satisfy my demand. My exports cover all of my imports, my standing charge, and my heat pump servicing. With some left over!

The idea that you could install batteries and generate an income from them was not a good justification for installing them.

It may have worked to some extent in the past but it was never guaranteed and if that was the reason you installed them you should have thought it through more.

Why don't you sell for 26.21p and buy back for 14.77p?

Surely that would make more sense if that is what you want to do?

debitcardmayhem

The latest tariff for flux has turned things around, you used to be able to buy at 13.xx (2-5) and sell at 15.xx (5-1600) . Now you make a “loss” , but gain more 1600-1900 buy forcing export. But then the battery in my case won’t cover my usage from 1900-0200. Agile and fixed export may work out better but needs constant monitoring. The other side of the downside is that if you export between 16-19 then you can’t realistically take part in DFS by exporting during the saving sessions, which could be more lucrative, I benefitted by over £100 in the earlier sessions lat year, but hospitalisation stopped me make the best of the 2024 ones.

Scot_39

Solar or battery export was never a guaranteed income.

The ever growing level of renewables - several GW per year for install online targets per year being licensed in recent auctions rounds - even allowing for previous to last auctions offshore failings - changes the market balance significantly.

The UK now has an excess peak electrical generation capacity.

And a rapidly growing domestic solar PV - up near third in last 2+ years.

If add up fossil, nuclear, grid level solar (ave let alone peak), grid level wind (ave let alone peak) it already far exceeds demand.

Add in another c5GW domestic solar [3.7kWp ×1.4m = 5.2 GW] in summer when demand runs at c25 GW - you might just see the problem beyond your own meter.


We have net zero preference (not cost preference - wind CfD alone adding 1.45p per kWh - to wholesale in cap price) grid level renewables capacity swapping in when available, fossil capacity in standby for when it is not and nuclear generation fixed on non load following plant or contracts.

There is therefore at times very little commercial demand for micro generated power.


Now that may change again in future - as more move from GCH and ICE - but they are not best seasonally or even daily - suited to solar - but may be more eo for your battery model  - but right now total generation capacity growth is leading demand growth. 

And people sharing their excess - dumping it into an often crowded oversupply market - for payment - should no longer be considered normal.  It cetainly isn't in other nations.

Why should you get paid above market 1/2 hr settlement bid auction linked rates.  Rates that can see those on Agile pay far less per kWh in the same time slots.

UK maybe not their yet - but it could be as near c150,000 per year have added solar in last couple of years in response to energy crisis pricing. 

And solar uptake highly regional - peaking at near 14% of homes - in parts of Wales and Devon/ Cornwall etc in S West.  Getting on for 1 in 7 homes.  And you can bet it's focused on wealthier areas in many.  

My home use 25-100W when house empty during day in summer - it would take dozens or hundreds like me to absorb someone exporting c4kW.  Far far beyond 1 in 7.

There just isn't local demand for the power at 230V DNO level as install density increases.

In a grid system designed for top down voltage and frequency regulation / management not bottom up - that becomes an issue.

And so in some sunnier nations - Solar PV export capped or even not an option. 
You might see solar water het tanks on every other roof etc but not solar PV export at UK scale - not peak ukm density anyway. 
In some areas - you wont get an export license at all - in others it will be capped to an absolute and modest max - so only able to export fraction of typical solar / invertor ratings. 

Solar - or excess solar above export limit - in those areas - for own demand only. Not for sale.

NedS

Scot_39 said:

Solar or battery export was never a guaranteed income.

The ever growing level of renewables - several GW per year for install online targets per year being licensed in recent auctions rounds - even allowing for previous to last auctions offshore failings - changes the market balance significantly.

The UK now has an excess peak electrical generation capacity.

And a rapidly growing domestic solar PV - up near third in last 2+ years.

If add up fossil, nuclear, grid level solar (ave let alone peak), grid level wind (ave let alone peak) it already far exceeds demand.

Add in another c5GW domestic solar [3.7kWp ×1.4m = 5.2 GW] in summer when demand runs at c25 GW - you might just see the problem beyond your own meter.


We have net zero preference (not cost preference - wind CfD alone adding 1.45p per kWh - to wholesale in cap price) grid level renewables capacity swapping in when available, fossil capacity in standby for when it is not and nuclear generation fixed on non load following plant or contracts.

There is therefore at times very little commercial demand for micro generated power.


Now that may change again in future - as more move from GCH and ICE - but they are not best seasonally or even daily - suited to solar - but may be more eo for your battery model  - but right now total generation capacity growth is leading demand growth. 

And people sharing their excess - dumping it into an often crowded oversupply market - for payment - should no longer be considered normal.  It cetainly isn't in other nations.

Why should you get paid above market 1/2 hr settlement bid auction linked rates.  Rates that can see those on Agile pay far less per kWh in the same time slots.

UK maybe not their yet - but it could be as near c150,000 per year have added solar in last couple of years in response to energy crisis pricing. 

Gary does Solar on youtube talked about this issue recently here:

https://www.youtube.com/watch?v=4loz5EAHVUY

Scot_39 said:

And solar uptake highly regional - peaking at near 14% of homes - in parts of Wales and Devon/ Cornwall etc in S West.  Getting on for 1 in 7 homes.  And you can bet it's focused on wealthier areas in many.  

My home use 25-100W when house empty during day in summer - it would take dozens or hundreds like me to absorb someone exporting c4kW.  Far far beyond 1 in 7.

There just isn't local demand for the power at 230V DNO level as install density increases.

In a grid system designed for top down voltage and frequency regulation / management not bottom up - that becomes an issue.

And so in some sunnier nations - Solar PV export capped or even not an option. 
You might see solar water het tanks on every other roof etc but not solar PV export at UK scale. 
In some areas - you wont get an export license at all - in others it will be capped to an absolute and modest max - so only able to export fraction of typical solar / invertor ratings. 

Solar - or excess solar above export limit - in those areas - for own demand only. Not for sale.

This is also a real issue. As you elude, our infrastructure isn't designed for many small sources of generation. When we export excess solar, it is consumed locally by our neighbours. It is generally not transmitted back up the grid past our local transformer.

Once more people apply for export than can be consumed downstream of the local transformer, the DNO has to deny (or limit) those applications, or upgrade the local transformers to allow excess to flow in the opposite direction. Of course this is exacerbated by the fact peak domestic production occurs during the middle of the day, just at the time when consumption is lowest in many cases as people are out at work. Batteries can help by storing excess daytime generation for evening/night time usage.

I expect to see the size of DNO export approvals fall now solar is reaching critical mass, and suspect the days of 15p SEG are numbered. Maybe we will reach a point where solar can only be installed alongside battery storage for later use with no export. Maybe we will see intelligent inverters that the energy companies can control to vary the amount of export based on real time demand.

Scot_39

The grid can tell grid level renewables not to generate (at a cost).

It can tell fossil plants to sit in standby and or not generate (at a cost)

But it has no control over what now could be c20% of demand in summer.

And in high density areas - possibly exceeding that.

The only easy cut off (inaction rather than action arguably)  and then people complain is if do let voltage levels rise and so rely on modern solar invertors eventually cut themselves off - in which case their owners complain.

Scot_39

NedS said:

I expect to see the size of DNO export approvals fall now solar is reaching critical mass, and suspect the days of 15p SEG are numbered. Maybe we will reach a point where solar can only be installed alongside battery storage for later use with no export. Maybe we will see intelligent inverters that the energy companies can control to vary the amount of export based on real time demand.

My uncle in Aus was capped - many years after installing his solar - ironically when extended his array - he ended up unable to export as much in theory - the cap iirc just over 60% of new invertor rated - - but he needs to run air con 24/7 in summer - so wasn't a big issue for him.

His neighbours were forced to upgrade their invertors or controllers if lucky - to apply the retrospective cap - a year or so later.

People with existing export permission may not be as safe as they might think.

My cousin - different regional provider - moved into a new home - nearer town - same supplier roughly same solar ratings - but couldn't export at all - at the new address (a city wide ban ) - due as you elude - to local grid saturation issues - despite the prevalence of energy hungry domestic air con.

But then their average solar density is something like 30% homes iirc - twice current UK peak - but UK being growing rapidly.  And many will have lower demands.

I''ve also rented in Southern USA - - expensed to employer so not my problem - Texas, Alabama - with solar arrays - and no export payments

MP1995

Battery export will surely outlive solar. We are getting to the point where we produce too much solar for the demand during the day so I expect solar export prices to plummet over the next few years.

Batteries though, that can be controlled by your Energy provider,and you grant them control means a future where you can sell your battery stored power for much more than solar can ever be sold for.

Just my opinion if anyone is considering one or the other and not both solar and battery.

Reed_Richards

Allude: 

suggest or call attention to indirectly; hint at.

"she had a way of alluding to Jean but never saying her name"

Elude: 

escape from or avoid (a danger, enemy, or pursuer), typically in a skilful or cunning way.

"he tried to elude the security men by sneaking through a back door"

Scot_39

Reed_Richards said:

Allude: 

suggest or call attention to indirectly; hint at.

"she had a way of alluding to Jean but never saying her name"

Elude: 

escape from or avoid (a danger, enemy, or pursuer), typically in a skilful or cunning way.

"he tried to elude the security men by sneaking through a back door"

We stand corrected

Netexporter

Anyway, I'd have thought siting some battery storage at every area substation would be a good start. Soak up excess solar for the evening peak, fill up the previous night if there is going to be a shortfall in the following day, just like a home battery on a larger scale. Very quick to install, as they are usually containerised units, just needing a firm base to be sited on, and prices are are at rock bottom, currently. It would buy a bit more time whilst bolstering the high voltage grid.