UK's largest battery storage facility at Tilbury substation
106 comments
·September 1, 2025myrmidon
AnotherGoodName
Check out https://en.m.wikipedia.org/wiki/Hornsdale_Power_Reserve
63days from start to completion. Paid itself off in 2 years. Saved consumers well over $100million/yr across the state in power bill reductions (only 1.8million people in that state and this is after the battery owners took their profit).
There's really nothing but positives from grid scale batteries. They cut out all those <0 and >100x price fluctuations on the grid and the payoff for investors is ridiculous right now.
Australia's expected to 20x it's grid connected battery capacity between 2024 and 2027. The growth in battery storage is ridiculous since the costs have come down. https://elements.visualcapitalist.com/top-20-countries-by-ba...
curtisblaine
> There's really nothing but positives from grid scale batteries
I'm pretty sure they have a matching number of positives and negatives.
rwmj
Is it 300 or 600 MWh? Or is the storage 600, but it can deliver 300MW/h?
Edit: The company press release is much clearer: https://stateraenergy.co.uk/news/thurrock-energisation The storage is 300 MWh, but it can deliver a peak of 600 MW/h (presumably for half an hour).
nicoburns
The orginal article is pretty clear:
The 300MW Thurrock Storage project... with a total capacity of 600MWh
riedel
The OP says it the other way around though. Power is 300MW and capacity 600MWh=2h*300MW. There is no mentioning of 300MWh in the OP.
iaebsdfsh
Storage is measured in MWh, power in Watts, I think the original press release is wrong and it can output 300W for at most two hours. The following link confirms that: https://www.ess-news.com/2025/08/18/statera-energy-powers-up...
pietjepuk88
> The 300MW Thurrock Storage project, developed by Statera Energy, is now energised and delivering electricity flexibly to the network across London and the south east.
> With a total capacity of 600MWh, Thurrock Storage is capable of powering up to 680,000 homes, and can help to balance supply and demand by soaking up surplus clean electricity and discharging it instantaneously when the grid needs it.
Unless they updated the original post, that all sounds correct to me. It's a 2-hour battery, rather common in the industry.
EDIT: Ah, you mean the https://stateraenergy.co.uk/news/thurrock-energisation is wrong, with the fantastically outrageous statement of "delivering its full output of up to 600MWh within seconds."
nickdothutton
As an aside, this is exactly the kind of nonsense you get when marketing or PR firms have control over final wording. Once had someone change "uninterruptible power supply" to "non-interruptible" and then finally "interruptible" and that is how it went out in the final press release. There was some harsh language that day.
ragebol
> This landmark 300MW battery storage site is capable of powering up to 680,000 homes with instantaneous power over two hours
Power is 300MW (300000000 Joules/second), which it can deliver for 2 hours, so capacity (energy contained in the device) is 600 MWh (or 2160000000000 Joules)
adamm255
Time to decouple the UK Electricity price from Gas so we can actually reap the benefits of this as a consumer.
trebligdivad
It effectively decouples for any period when no gas is needed; so if those batteries let you turn off the gas generators for an hour the price decouples from gas.
u02sgb
Think OP is taking about UK bills which are coupled too the cost of gas for historical reasons. Which needs to change in my view too.
trebligdivad
Right - but if we start getting a useful amount of time when the grid doesn't need any gas, the amount of coupling should start to drop off.
jacquesm
That will never happen. They'll use that excuse until the very last gas powered plant is alive and then there will immediately be some other reason why energy prices have to stay the way they are.
ZeroGravitas
The only sensible way to do this I've heard is to roll out more renewables faster and so burn less gas.
Is there some other plans you support?
SideburnsOfDoom
While this is worthwhile, I think that the parent post may be referring more to the "UK Electricity price" to consumers, and how this is calculated. It is related, but not quite the same as "roll out more renewables faster and so burn less gas"
https://www.theguardian.com/business/2025/apr/20/why-the-uks...
> "If we actually paid the average price of what our electricity now costs to produce, our bills would be substantially cheaper."
> In simple terms: the price in the electricity market on any given day is dictated by the most expensive source of generation available, which in the UK would be its gas-fired power plants.
I support "roll out more renewables faster" and pricing reform. Linked article makes it clear that the UK has "one of the most expensive electricity markets in the world" and this impacts consumers and businesses.
Which does raise the question: who benefits from the current pricing arrangement, and why do they have the deciding vote?
CorrectHorseBat
Is this not simply how markets work? Everything is sold at the marginal price.
You could change that, but it would just mean prices will be higher at another moment (in a perfect market), no?
skippyboxedhero
Rolling out more renewables faster will mean more reliance on gas.
I am not sure how people still don't realise this after ten years of doing this and energy prices going up non-stop.
myrmidon
We did not start to push for renwable energy to get prices lower, this is mainly a mitigation against previously unaccounted-for externalities (CO2 emissions and air pollution).
Complaining about transition costs, to me, is like complaining that industrial waste disposal was cheaper back when we just dumped everything into the next river.
nicoburns
Only needing gas when the renewable energy isn't available seems strictly better than needing gas 24/7
rcxdude
At this point, there's not that much other non-renewable generation on the UK grid, so expanding renewables will reduce the impact of gas on prices (though it'll likely be non-linear).
myrmidon
You do realize that this is coupled with a 450MW gas power plant?
Gas is a really appealing backup option for both renewable and nuclear powered grids (at least in the absence of freely available hydropower).
But as installed power/capacity grows and batteries get cheaper, reliance on gas will hopefully decrease (and supply might get bolstered by renewable-powered synthgas within the next decades).
cjrp
It's more about the negative effect that using gas has on the wholesale price of energy; electricity prices are determined by the most expensive source at that point in time. So we either need to get gas usage to 0, or change how that wholesale price is calculated in order to see a consumer benefit.
stuaxo
Its attached to the national grid, so surely it can also charge of the grid as needed too.
boredpudding
Does the UK not have an option for hourly-pricing? That's usually where as a consumer you can have the most gains. In the summer, with solar panels, my energy bill is negative (in The Netherlands)
Havoc
The UK has a stupid system where the pricing for everything is determined by the most expensive thing in the mix:
>The UK’s electricity market operates using a system known as “marginal pricing”. This means that all of the power plants running in each half-hour period are paid the same price, set by the final generator that has to switch on to meet demand, which is known as the “marginal” unit.
i.e. if you have 99 units of solar but have 100 demand, 1 unit of gas plant fires up to fill it then all 100 units are compensated at the gas rate even if the wind was cheap.
0rdinal
Some suppliers (e.g., Octopus Energy) offer half-hourly tariffs whose rates track the day-ahead wholesale market and are published daily. Prices usually fall when supply is abundant (e.g., windy/sunny periods)
Day ahead pricing: https://agileprices.co.uk/ National grid supply/demand and energy mix: https://grid.iamkate.com/
rcxdude
Yes, but the hourly price is still largely set by gas, because it's still a minority of the time where renewables are supplying 100% of the grid.
Kognito
We do, but I can’t imagine it’s hugely popular. Only a few of the smaller suppliers offer it AFAIK.
zeristor
There was the largest one in Scotland a few months ago.
These are, dare I say it, the easy wins. Reusing the infrastructure from a demolished coal fired power station.
However I have yet to see Battery storage feature in the charts for UK energy usage yet.
I’m guessing that there are a lot of similar such sets that are being, or could be repurposed for battery storage.
WJW
We had an interesting case here in the Netherlands, where at the moment the biggest problem for big battery operations is to get sufficient grid transmission capacity. One clever company bought the site of a bankrupt aluminium smelter for cents on the euro, purely because said smelter had a direct high capacity connection to the national high voltage grid. Getting the rest of the site and the machinery was just a bonus.
jacquesm
Yes, Aldel. I think that will pave the way for more moves like that. They have yet to install anything but the financing is there:
https://giga-storage.com/giga-storage-rondt-financiering-van...
DamonHD
Lots of good stuff in here: https://www.gov.uk/government/publications/clean-power-2030-...
blitzar
> However I have yet to see Battery storage feature in the charts for UK energy usage yet.
There are also four pumped-storage hydroelectric power stations providing a further 2.8 GW of installed electrical generating capacity, and contributing up to 4,075 GWh of peak demand electricity annually.
https://en.wikipedia.org/wiki/Hydroelectricity_in_the_United...
ZeroGravitas
On one of the sources of grid usage it has a placeholder for batteries but says:
> Several battery storage systems are in operation in Great Britain, but full reporting is not yet available: reports include discharging but not charging. As this would lead to double counting, with power being reported both when originally generated and when discharged from battery storage systems, battery storage data is not yet shown on this site.
DrScientist
Conceptually it is no different from pumped hydro storage. - for that they simply use negative numbers for pumping and positive for release.
I guess it's some technical problem with standardisation/tracking/reporting of the charging right now.
As/if Vehicle-to-Grid becomes more widespread, where you have highly distributed battery storage, it will be interesting to see if this will be publicly tracked.
Already domestic solar production is largely invisible ( as that mostly manifests in reduced demand ).
However I assume, in terms of managing the grid day to day, that such information is going to be important. ( eg if it's a largely cloudly day then that will be manifest as a rise in domestic demand ).
arethuza
Probably this one: https://www.zenobe.com/news-and-events/blackhillock-battery-...
Very much aimed at storing surplus from a couple of wind farms in the Moray Firth.
Presumably we'll see a lot more of these given the scale of some of the new windfarms...
ZeroGravitas
That one claims to Europe's biggest, this one is claiming to be the UKs biggest which I guess means an even larger one went live in Europe somewhere in between.
femto
> However I have yet to see Battery storage feature in the charts for UK energy usage yet.
Grid connected batteries are more about aiding grid stability, filling short term mismatches between loads and renewable generators, rather than raw capacity in terms of kWh.
jacquesm
It will be a long time before you will. That's just not the best application right now.
tpogden
For comparison with a gravitational battery, Dinorwig pumped hydro in north Wales has a max power output of 1.7 GW and storage of 9.1 GWh.
ZeroGravitas
About 10-15 percentage points less efficient because of losses pumping the water uphill though, and slower to react (seconds vs milliseconds) which will probably force it out of the fast frequency response market which batteries have rapidly saturated.
3eb7988a1663
Batteries are not perfect either. The EIA published numbers that grid scale batteries were something like 81% roundtrip efficiency.
jacquesm
It's pretty much tailor made for batteries and flywheels. 2 seconds is not feasible for pumped hydro, though it still is impressively fast at less than 30 seconds. It is interesting how all of these technologies have their sweet spots.
philipwhiuk
The title change rather obscures the actual event that occurred - that this facility is now connected to the grid...
jeffbee
Do the fission bros shrivel up a little every time one of these goes online? "But my base load!" they shriek as they vanish into an infinitesimal point.
Temporary_31337
What is the chemistry and expected lifetime of the batterries? They are saying this is for sustainable energy future but it looks like it's using natural gas (not sustainable) powered energy to charge up Lithium(?) batteries that will need to be replaced every n years (also not sustainable). Which part of this facility makes it more sustainable?
chippiewill
Why would they charge up with natural gas?
The UK often has excess wind energy, and for Tilbury in particular that problem is set to grow as National Grid are building out massive grid capacity from the North Sea wind farms through Tilsbury
Hilift
A similar project in Australia used Tesla megapack batteries, which are lithium ion.
Another form of stored energy uses thermal. A large scale project to plug ~50,000 idle and abandoned oil wells in Kern County, California.
Probably worth noting that for states and utilities, consumer solar without batteries has become a liability and doesn't scale up. So effectively, all future consumer solar installations in California will likely have batteries. So there will be batteries at the consumer point, and centralized large scale battery farms like this one to address peak demand and prevent situations where blackouts may need to occur.
https://eepower.com/news/engineers-repurpose-oil-wells-as-so...
ViewTrick1002
Generally LFP with cycles in the at least 5000 range.
They are pure arbiters of the market. Filling up when it makes sense and delivering when it makes sense. Which sometimes means buying expensive fossil gas powered electricity to sell it even higher priced later.
But what this means is that at that ”later” the peaking plant that originally has been used did not have to start and consumers enjoy cheaper electricity.
But what they do is extend the time renewables deliver. In for example California storage has reduced fossil gas usage by 40% in recent years.
rsynnott
> With a total capacity of 600MWh, Thurrock Storage is capable of powering up to 680,000 homes, and can help to balance supply and demand by soaking up surplus clean electricity and discharging it instantaneously when the grid needs it.
I mean, I get what they’re saying, but I’d certainly hope it is not capable of discharging 600MWh _instantaneously_!
beAbU
Would like to be around when that happens though, should be quite the spectacle!
okasaki
Cool so when will this translate into cheaper energy? Why am I paying $0.4 per kwh?
AnotherGoodName
Pretty much straight away actually.
In Australia prices were reduced by over $50 a year per person in the state on average once a similar battery went online. Similar policies and market there to this case too. Details: https://en.m.wikipedia.org/wiki/Hornsdale_Power_Reserve
I get that it's easy to be pessimistic but batteries like the above not only pay themselves off in 2years (From the article above, $46million profit in one year alone on a $90million install cost!) they also cut prices on the grid from day one.
Behind the scenes prices can fluctuate between <0 and >100x baseline. These types of installations immediately smooth out the costs. As long as you have competing wholesalers/providers the price reductions will come through pretty quickly based on similar cases.
hdgvhicv
One issue the U.K. has is a grid bottleneck but wiggle pricing across the grid. While excess power may be available in some places, there’s not enough interconnection to move it where it’s needed, so those with excess power (lots of wind etc) can’t benefit.
3eb7988a1663
If the batteries are installed south of the interconnect, won't that help the problem?
benrutter
I think a big reason for net-zero policies getting bad press, is that these kind of things are difficult to quantify. Energy is largely set by gas price, so having more non-gas assets on the grid probably means you do have cheaper energy (or, at least will have much cheaper energy in the future when gas ceases to dictate the energy price)
I guess what we can't do is step into the alternative world where there's less batteries and renewables, and complain about paying $0.6 per kwh.
rwmj
This project won't do anything (as you likely already know). The reason electricity is so expensive is because it's tied to gas prices, which is an entirely political decision.
xnorswap
Isn't the price tied to the marginal price, rather than the price of gas?
Even if they're typically the same, because CCGT is the best for on-demand generation, flattening the demand curve ought to slightly reduce that marginal cost.
I've seen the UK generation market attacked quite a lot lately, but to me it makes sense to price everything at the marginal cost, and doing so also helps encourage capital investment in generation that can have lower generation costs themselves, because the marginal cost is only slowly impacted rather than a boom and bust model.
chippiewill
I agree, although I think one of the disadvantages in the UK is that the suppliers aren't paying the cost for their own volatility. A renewable supplier can add 1GW supply to the grid, but 1GW of natural gas generation capacity is still required.
Fixed costs and capital costs end up being shouldered by the consumer which ironically ends up pushing overall costs up.
justincormack
Yeah we still need some more renewable capacity (and transmission) before gas usage can go to zero much of the time (which will need more batteries to deal with short term fluctuations). Right now we are using around 10% gas, which is a decent amount. Prices are still going negative at night some of the time, like last night.
ZeroGravitas
Batteries will reduce the number of times gas sets the marginal price, so they will have a near immediate impact on that.
They'll also likely reduce the balancing costs by relieving congestion.
Probably too small to notice among all the other costs and changes, like deploying more renewables and starting to pay in advance for new nuclear.
tomatocracy
The current marginal market price is not the same as the current average price being paid for all electricity delivered. A lot is delivered via fixed price arrangements of one sort or another (CFDs, PPAs, etc) and then there are things like the Balancing Mechanism which is paid as bid, and capacity payments which are outside the marginal cost per kWh part of the system.
mytailorisrich
Gas prices are a political decision, too in Europe. For demand to reduce and for other sources to be more competitive prices have to be and remain high.
In the UK I believe it is policy for electricity prices to be high in general for thse reasons and to encourage lower usage.
skippyboxedhero
Retail energy prices are subsidised. It isn't policy to encourage lower usage, the government is paying billions to sustain retail consumption (and yes, this is whilst another part of the government is driving prices higher).
The issue in the UK is that we moved to renewables that can't produce energy at the margin, marginal prices are still driven by gas, and we simultaneously decided to shut down large amounts of non-renewable sources of energy to satisfy the ambitions of politicians.
Result? Highest energy prices in the world, most energy-intensive industry shutting down, and massive reliance on political direction/regulators by industry (the original comment is not right, since the mid-2010s energy companies have been directed day-to-day by the state, invest in this project, don't do this anymore, etc. Our policy is made by people who wish the world was a certain way, reality doesn't matter to them).
blitzar
I'm paying £0.06 at the moment and I got paid to use electricity on the weekend thanks to the sun shining and wind blowing.
beAbU
I call bullshit on this claim. Sure, you might be paying pennies a kWh, but likely only for a few hours at midnight, then it spikes to £0.50 during peak times.
okasaki
I don't know how you're accomplishing that.
The lowest mine goes is $0.3 1am-4am.
scrlk
Probably on a half-hourly tariff, e.g. Agile Octopus: https://www.octopriceuk.app/agile
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rcxdude
Once there's enough renewables and batteries that the UK is running off of near 100% renewables a decent fraction of the time, so the price is not being set by the gas turbines making up the margin.
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happosai
If you are paying for electricity in dollars, this battery won't translate to cheaper energy for you. The battery is in Scotland.
hgomersall
Essex
okasaki
I'm just translating for USD for an American audience.
gadders
Not really. The higher proportion of renewables a country has, the more expensive the energy. See the chart on this page:
https://ca.finance.yahoo.com/news/bjorn-lomborg-solar-wind-p...
grues-dinner
Alternatively, the higher the cost of non-renewable energy in a country, the more attractive renewables are in that market.
If gas costs £1 a unit and solar is 90p, solar is profitable (especially if you get paid the gas price). If gas is 50p a unit, solar isn't going to be much of an investment.
ZeroGravitas
Bjorn Lomborg is a hack propagandist and that is obviously bad science.
Just look at all the unnamed points in the lower left that are actually creating the trend he claims to have found.
If you graph developed nations the correlation reverses.
triceratops
Fires burn wherever firefighters show up, it's weird.
Lio
Personally, I'd take Bob Ward's analysis over Bjorn Lomborg's.
https://www.lse.ac.uk/granthaminstitute/news/more-misinforma...
gadders
I'd like to see them debate. All I know is my energy cost keeps going up in the UK, and we seem to have some of the most expensive energy in the world.
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tomdickandharry
[dead]
Found some older article on financing/timeline since there's not much info here:
https://www.ess-news.com/2024/11/05/financial-close-for-uk-p...
The battery storage was ~$200M. Pure prismatic lifepo cells are currently ~$60 per kWh in single digit quantities (would be $40M or 20% of total costs, which seems reasonable). The attached 450MW gas power plant cost ~$350M.
I find it rather remarkable how they aquired the contracts in early 2023 and the thing is already running.