Bill Ponton’s “Reality Check” On UK Wind Power: The Issue of Energy Storage


Francis Menton

Bill Ponton’s new Report, “The Cost of Increasing Wind Power: A Reality Check,” contains a short but pithy section addressing the question of energy storage. Here’s the question to be addressed: If after the first round of overbuilding, adding new wind generation resources adds little useful energy and most of the added generation ends up getting “curtailed,” then why not just add some batteries or other energy storage to the system? Wind energy advocates suggest that some form of batteries can store the excess electricity production until it is needed, and everything will then just balance out in perfect equilibrium.

Is there any problem here? Ponton does the simple calculations with his UK 2022 spreadsheet to derive how much storage in GWh will be needed, and what its functional characteristics must be. His results are very similar to the results of comparable exercises previously undertaken by Roger Andrews for California and Germany, and Ken Gregory for the U.S.

The main problem identified by Ponton is the same one previously identified by Andrews and Gregory. Before you even get to the very high cost of storing electricity, there is another huge hurdle, which is that the availability of wind to generate electricity varies with a seasonal pattern. Therefore, to match electricity supplied to electricity demanded, the storage balance must be built up over about a six month period to an enormous level, and then discharged over the following six month period.

Ponton considers the case of a tripling of UK wind generation rated capacity, from the current 28 GW to 84 GW. Average usage is about 35 GW, and peak usage is about 45 GW; so the 84 GW of rated wind capacity provides plenty of spare electricity to charge the batteries when the wind is blowing at full strength, or even close to that.

Ponton next assumes purchase of 12,000 GWh of battery storage capacity. With that in place, here is his chart of additions and withdrawals from storage based on the UK 2022 data:

You can immediately see that the wind is much stronger and more consistent in the Spring and Fall than in the Summer. Then, here is the chart of the storage balance, assuming you initialized the system with zero storage at January 1, 2022:

The batteries build up to the 12,000 GWh maximum by about March, then discharge through September, and then begin building the storage balance back up starting in October. On the particular weather pattern of 2022, the 12,000 GWh of storage capacity was sufficient to get through the year, with the minimum stored amount in September being more than 1,000 GWh.

For readers who don’t recall the previous results from Andrews and Gregory, here is Andrews’s comparable chart for California based on 2017 data:

And here is Gregory’s chart for the U.S. with two different lines representing 2019 and 2020 data, both again showing the characteristic seasonal pattern:

All these results clearly illustrate the problem that the energy storage to accomplish the task of using the excess production from wind must have both very large capacity and the ability to charge and discharge in one grand annual cycle. Ponton’s comment:

Batteries do not exist that are up to the task of such long-term energy storage.

Pumped water storage does at least theoretically have the ability to charge and discharge to meet this criterion of an annual cycle, but it also has the problems of enormous cost and, even more important, complete lack of sufficient suitable sites. Ponton:

If there were sites in the UK for pumped storage, it would cost $2 trillion. The UK would have to construct 500 pumped storage facilities with 24,000 MWh capacity [each]. Each would be comparable in size to the largest facility in existence at Bath, VA, which cost $4 billion to construct.

My own comment: Ponton’s illustration of 12,000 GWh of storage needed to get through the year represents about 14-15 days of average usage in the UK. That figure is quite low compared to the amounts of storage found by Andrews and Gregory to be needed for California and the for entire U.S., which are in the range of 25-30 days of average usage. I think the difference is explained by the following things:

  • Andrews and Gregory assumed a renewables mix of wind and solar facilities in similar proportion to what exists currently in California and in the entire U.S., respectively. Ponton assumes only wind as the renewable addition. This makes a substantial difference because solar generation is much more seasonal even than wind, and operates at a much lower average annual capacity factor. (Note that both California and the full U.S. have substantial solar in the mix. Since solar is strongest in the summer, the peak of the annual charge/discharge cycle in the Andrews and Gregory spreadsheets is later in the year than in the Ponton spreadsheet. But the annual cyclical pattern is basically the same.)
  • Ponton assumes that the “other” category of generation currently existing in the UK remains in place. This “other” category consists of a mix of things like coal, nuclear, hydro and biomass, most or all of which may well be on the environmentalists’ chopping block. As shown on Ponton’s charts, the “other “ category operates at a quite steady 10 or so MW, covering almost a third of the UK’s average usage like a “baseload” generator. The continued existence of this “other” category substantially reduces the annual seasonality of production over what would be the case of wind was expected to take over all power generation.
  • Ponton has no assumptions for losses in storage, such as the loss from every charge/discharge cycle, or the dissipation loss from having energy stored in a battery for months on end. Since the costs he comes to are already ridiculous before adding these additional elements, he can be forgiven for not continuing to beat the dead horse.

Ponton does not compute prices for 12,000 GWh of storage using lithium ion batteries, which is reasonable since those batteries are not up to the job of storing energy for 6 months to a year without catastrophic loss. But just to give an idea, at $250 per kWh (lower than current prices for grid-scale storage), 12,000 GWh would run about $3 trillion — approximately equal to the entire annual GDP of the UK. If you start trying to shift the coal and nuclear production in the UK to wind, and if you then consider major losses from trying to store power for up to a year before use, you can multiply that $3 trillion by a factor of 2 or 3 or maybe 4. Whatever.

As stated many times at this site, this will never happen. The only question is how disastrous the crash will be when it all falls apart.

Again, many thanks to Bill Ponton for putting in the work to demonstrate these issues, all without compensation.

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April 5, 2023 2:14 am

Tell me again, why are we trying to reduce CO2??

Reply to  Paul_Rossiter
April 5, 2023 2:52 am

That is the leading question and there is no science to support a need for reduction.

Leo Smith
Reply to  Paul_Rossiter
April 5, 2023 3:01 am

We aren’t. It is an excuse to raise energy prices and shaft the plebs.

Joseph Zorzin
Reply to  Paul_Rossiter
April 5, 2023 5:26 am

because it’s been declared to be a pollutant that is boiling the oceans- that’s true, Al Gore said so /sarc

Reply to  Joseph Zorzin
April 5, 2023 11:45 am

Al needs to spend a couple hours in the “boiling oceans” off Greenland. End of story.

More Soylent Green!
Reply to  Paul_Rossiter
April 5, 2023 5:53 am

Reducing CO2 isn’t the goal. It’s a head fake. The goal is to completely re-engineer our governments and economic systems.

Reply to  Paul_Rossiter
April 5, 2023 6:04 am

Because it has been proclaimed an evil gas, even though without it no flora and fauna could exist. Go figure

Reply to  Paul_Rossiter
April 5, 2023 11:21 am

Exactly. Take a look at how desperate they’re getting to meet Net Zero targets.

Seize property to build wind and solar farms, says JP Morgan chiefGreen projects must be fast-tracked to meet net zero targets

AGW is Not Science
Reply to  Sommer
April 6, 2023 7:01 am

If they want to seize property, let them start with JP Morgan chief Green’s mansion as a “trial” for such “policies.”

Then let’s see how he feels about the “need” to do that.

April 5, 2023 2:23 am

No matter how many times they bang their heads against the wall it simply isn’t going to work

Leo Smith
Reply to  strativarius
April 5, 2023 3:03 am

It isn’t meant to work. That is clear to everyone. It is there to participate in the transfer of wealth from the plebs to the elites, and power from the individual to the corporate and the state.

Reply to  Leo Smith
April 5, 2023 3:24 am

It isn’t clear to Starmer, Miliband, Sunak and the rest of the snouts in SW1A 1AA

Nor is it clear to the erstwhile occupants of Fleet Street

Reply to  strativarius
April 5, 2023 7:28 am

It’s not expected to work. Because it cannot work.
Do you think Starmer hasn’t asked how much backup would affect energy bills? Do you think Sunak hasn’t asked how much backup would affect national debt?
These people aren’t Truss or Johnson. They are both clever, keen to achieve their aims and also politically skilful.
So, if they know this won’t happen, why not admit that it won’t happen?
A) There is a green minority in many constituencies who would turn that seat if the Green mantra was rejected by either party.

B) Saying you won’t do this means you have to say what you will do instead and that would also be very expensive with the worse condition of, maybe, actually having to do it.

C) The only industry that the UK can keep at the moment is being supported by state intervention. Green initiatives, like defence, are saving the nation from harm and so the subsidy can be justified in terms of the national interest. The economy needs every stimulus it can get as growth and productivity have been flat-lining since the Coalition’s austerity slammed the brakes on Darling’s
recovery from Lehmann Bros.
Simplistically, stopping Green nonsense is politically impossible without a major campaign against the last thirty years of AGW propaganda.

Reply to  MCourtney
April 5, 2023 10:12 am


Ben Vorlich
Reply to  MCourtney
April 5, 2023 1:13 pm

That’s a very good synopsis of the situation in the UK

April 5, 2023 2:53 am

Story tip: Tower Hamlets (London) council, Low Traffic Neighbourhood obstructions and an angry Mayor. 

Last May, Lutfur Rahman was elected mayor of the London borough of Tower Hamlets. His local borough party, Aspire, also won control of Tower Hamlets Council. One key plank of Rahman’s manifesto was that he would scrap the borough’s unpopular Low Traffic Neighbourhood schemes that limit vehicle access to many roads and estates.

Tower Hamlets has since held consultations on the future of LTNs and many expect the council to announce their closure soon. In response, Transport for London (TfL) announced last week that it will punish Tower Hamlets by withholding £1million worth of funding every year until Rahman relents on LTNs.

There is now effectively a stand-off between a local leader, elected partly because of his promise to get rid of LTNs, and London’s Labour mayor, Sadiq Khan, who is committed to expanding them.

One can see why Rahman has moved to get rid of LTNs. These schemes were imposed without consultation by local authorities, with the support of the UK government’s Department for Transport, during the lockdowns of 2020 and 2021. They have divided communities across the country, advantaging some while disadvantaging many more. They have made it more difficult to drive in cities than ever before. And yet rather than listen to people’s concerns, local authorities have formalised and extended LTNs in Bristol, Oxford and, most extensively, London,

there is more to this conflict than just an unpopular traffic-reduction scheme. There has been a grudge between Rahman and the Labour Party for more than a decade now. In 2010, Rahman was chosen to be Labour’s candidate for the new mayoralty in Tower Hamlets, only to be blocked by the party’s National Executive Committee. Rahman proceeded to stand as an independent candidate in the 2010 mayoral elections, which he went on to win with 51 per cent of the vote – double that of the second-placed Labour candidate. And in 2014, he was elected mayor of Tower Hamlets for a second time, much to Labour’s chagrin.

TfL’s decision to deprive Tower Hamlets of £1million in funding every year seems vindictive and punitive. The money was supposed to be earmarked for improving bus services. Surely, if TfL wants people on buses rather than in cars it shouldn’t matter whether the local borough backs LTNs or not? TfL is controlled by the London mayor, so the decision is definitely personal.”

60% of Londoners stayed at home rather than vote for the dross that was on offer to be Mayor. You can see why.

Reply to  strativarius
April 5, 2023 6:21 am

He was found guilty by an election tribunal in 2015 of vote-rigging and banned from standing for election for 5 years. Hardly a paragon of virtue, Labour were probably correct (which doesn’t happen often) to ditch him. But amusing to see resistance to TfL and Sadiq Khan from across the political spectrum.

Reply to  strativarius
April 5, 2023 10:24 am

Low Traffic Neighbourhood schemes that limit vehicle access”
is that a euphemism for toll roads?

I used to use a toll road into a city knowing that the route could move quicker because different commuters make different time-money-style trades. Toll roads, public roads or public transportation were engineered to take the same total time and cost where I came from (egalitarian), but the time and money were spent very differently.

Engineered by whom?

It doesnot add up
Reply to  KevinM
April 6, 2023 4:11 pm

Well, I suppose if you count the fines issued by ANPR cameras and computers for those who elbow planters that block road turnings out of the way and ignore the street signs as tolls…. but the fines are rather higher than any tolls I’ve ever come across.

April 5, 2023 2:55 am

“Batteries do not exist that are up to the task of such long-term energy storage.”

Oh dear…

UK energy policy.png
Reply to  Alpha
April 5, 2023 6:00 am

Haven’t you heard of Moore’s Law… solid state batteries… sodium batteries… something will turn up? You gotta love the Green Luddites undying faith in technological breakthroughs. How I learned to stop worrying and love the BoM (with the help of a backup genny).

Peter C.
Reply to  observa
April 5, 2023 2:14 pm

Moore’s Law worked for a while in regard to chip density, but not any more.

The Real Engineer
Reply to  Peter C.
April 6, 2023 12:56 am

Yes, the basic problem is that atoms are not small enough! Then there is the cooling problem, a bit like batteries really.

Peta of Newark
April 5, 2023 4:12 am

From NetZero’s email of Monday: as attached.

Also in that email:
Net zero factsheet 6

Heads. Must. Roll.

Windfarms and CfDs Net Zero.JPG
Reply to  Peta of Newark
April 5, 2023 5:53 am

Heads roll? Dream on, Peta.

“As the US and Europe speed off into the distance in the global race for green industry, we are sitting back in the changing rooms moaning about the rules. Sore loser syndrome won’t win any jobs for Britain.” – Ed Miliband

That, to my mind, is superb delusion. The kind that forgives any financial setbacks

Reply to  strativarius
April 5, 2023 10:48 am

As the US and Europe speed off into the distance in the global race for green industry,
Is that the wind I’ve been feeling?

Dave Andrews
Reply to  strativarius
April 6, 2023 5:37 am

Miliband is a fool.

All of Europe’s five wind turbine manufacturers have been operating at a loss for well over a year and have been pleading for more subsidies from the EC. Early in 2022 Wind Europe wrote to Ursula von der Leyen asking for help and noted that the industry in Germany alone had lost over 50,000 jobs over the last 6 years.

David Dibbell
April 5, 2023 4:15 am

Good article.
The piles-of-coal, caverns-of-gas, small-footprint power plant, more-atom-splitters approach to reliable, affordable energy storage, generation, and utilization looks better all the time.

BTW, these forms of basic analysis do not need peer review and journal publication to have credibility. All the data is readily available, and straightforward spreadsheet computation readily reveals the intractable issues with battery or other large-scale storage concepts.

Reply to  David Dibbell
April 5, 2023 10:56 am

I remember a 1990s (late 1980s? Hard for me to find with the way super hero reboots have undermined Internet search capability) Batman Returns movie plot about an evil genius building energy storage for his power plant.

Funny, this is a direct quote from someone’s article about it. I _have_ to read the rest.

Max Schreck may have been a killer, but the Batman Returns’ villain had a plan that would have saved the world from a major modern-day problem.

Yesterday’s comic book villain… today’s super hero.

Reply to  KevinM
April 5, 2023 11:00 am


As always, if you thought you had a good idea, you were probably not first:

“One of the biggest problems with solar and wind energy is that the sun does not always shine, and the wind does not always blow, and Schreck’s capacitor could help to address this. Rather than being another one of Gotham’s villains, Schreck would have no problem rising to prominence on exactly what he promises in the movie; the capacity for growth in Gotham, and avoiding brownouts or blackouts on the energy grid.”

David Dibbell
Reply to  KevinM
April 5, 2023 12:01 pm

Not far from me. This was from 2011. Ultracapacitors. Hook a bazillion together, and problem solved! /sarc

I guess they are still in business.

April 5, 2023 4:23 am

So let me see if I’ve got this right… Not only must we pay for wind and solar generation equipment that will only be working half the time, we must also pay for battery storage that will be used less than half the time and that’s supposed to be cheaper than using fosssil fuels on an as-required basis. How can it possibly be?

James Snook
Reply to  atticman
April 5, 2023 6:10 am

It’s the sort of catastrophic economic result that is inevitable with a command economy, which western economies have now adopted to ‘fight climate change’.

The equivalent of Mao’s ‘Great Leap Forward’.

April 5, 2023 4:59 am

America’s homemade inflation and banking crisis is killing renewables. Together with that other colossal own goal, the Ukraine war. Renewable expansion was predicated on cheap money with near zero interest rates. That’s gone for the foreseeable future, and so has the renewable pipe dream.

Joseph Zorzin
April 5, 2023 5:19 am

“Pumped water storage does at least theoretically have the ability to charge and discharge to meet this criterion of an annual cycle, but it also has the problems of enormous cost and, even more important, complete lack of sufficient suitable sites.”

The climatistas, here in Woke-achusetts are fighting hard to terminate one of the few in New England- in western Massachusetts, which was built to pump water from the Connecticut River to the top of a nearby mountain.

They complain that when it dumps water back to the river it’s causing some erosion and when it raises water to the mountain it’s sucking up some fish. The company is trying to deal with these issues but the complainers are determined to stop it- since it’s due to get a new license from the feds. This facility made sense when there was a nuclear power plant in nearby Vermont which has shut down. Without the nuclear power it still might make sense when there is extra power available to pump the water up the mountain.

The problem here is that climatistas complain about every sort of energy production. For years they were promoting solar “farms” until those farms got closer to themselves- now they complain that forests are being destroyed to build the solar farms – and they want to lock up the forests for one and only one purpose- to sequester carbon. They ignorantly think the state can arrive at net zero nirvana solely from solar on buildings- which of course is impossible.

Reply to  Joseph Zorzin
April 5, 2023 11:56 am

The interesting, overlooked problem with pumped storage is the energy loss. Pumping the water up loses 50% of the potential energy. Using a turbine to generate power from the water loses 50% of the potential energy. So, only 25% of the potential energy is available. Similar economics for green hydrogen. Every transformation requires an energy loss.

Joseph Zorzin
Reply to  Mason
April 5, 2023 1:25 pm

I think it made sense- when the nuclear power station was working close by- as it had a significant excess of energy at night. But the enviros pushed to terminate it like all or almost all nuclear in New England. It might be highly inefficient now- but it’s paid for and we’re going to run short of power soon since we’re heading to a net zero apocalypse. So I think it should keep working.

AGW is Not Science
Reply to  Joseph Zorzin
April 6, 2023 8:51 am

Nah, better to let the Eco-Nazis shut down everything that works quickly, so it can collapse quickly and the voters will finally see the futility of it all and start voting the idiots out of power. (No pun intended.)

Joseph Zorzin
Reply to  AGW is Not Science
April 6, 2023 9:26 am

sounds good but preferably not MY power source- I don’t care to do without it

It doesnot add up
Reply to  Mason
April 6, 2023 4:27 pm

Your assumptions on pumped storage are pessimistic. The round trip efficiency is typically 75-80%, perhaps a tad lower than (very expensive) batteries which are typically just over 80%. There are some alternative storage technologies that are of similar efficiency, but they are for a variety of practical reasons confined to limited duration. Other forms of storage are much less efficient – at least if you properly account all the energy inputs – although some do make some use of low grade energy that might otherwise be wasted (e.g. Liquid Air Energy Storage, best located adjacent to both an LNG regas terminal for free coolth and a water cooled power station for some free warm up energy to regasify the air). Going via hydrogen is very inefficient, so it requires a fair whack of extra generation capacity. That actually gets significant use in filling in some of the gaps that you might have thought the storage was going to cover.

April 5, 2023 5:59 am

There are some major errors regarding the batteries.

1) Batteries must not be operated at less than 20% charge and not more than 80% charge, for 15 year live, per Tesla and Battery University

2) During that 15 year life, the batteries lose about 1% per year in capacity, compounded, i.e., they store less and less.

3) Any electricity passing through the battery has about a 20% loss, from HV AC connection to HV AC connection

4) At present, the turnkey cost of Utility-quality, grid-scale battery systems is about $600/kWh delivered as AC, per US EIA

The above 4 factors will increase the $3 TRILLION mentioned in the article to about $10 TRILLION in the real world

Reply to  wilpost
April 5, 2023 6:51 am

Excellent comment!

Given deteriorating battery life, you would probably need double the nameplate capacity.

Worse still you would need to spend those umpteen trillions every 15 years!

Reply to  Paul Homewood
April 5, 2023 7:45 am


This article sums up the ins and outs of battery systems


Dave Fair
Reply to  Paul Homewood
April 5, 2023 11:09 am

Music to the ears of crony capitalist profiteers and their puppet politicians and revolving-door Deep State denizens.

AGW is Not Science
Reply to  Paul Homewood
April 6, 2023 8:54 am

Yes, THERE’S the part that is always cleverly ignored, the endless replacements.

AND the fact that every energy input into those original facilities AND their all-too-frequent replacements come from…FOSSIL FUELS.

A tail chasing exercise in futility.

Reply to  wilpost
April 5, 2023 10:10 am

2a) The more energy a battery is holding, the faster it will degrade.
2b) Each time a battery is cycled from full to empty or vis-versa, it degrades.
2c) The hotter a battery gets, the faster it will degrade.

Joe Public
April 5, 2023 6:25 am

A couple of salient points:

1) The ‘UK’ comprises England + Scotland + Wales + Northern Ireland.

His data refers to Great Britain i.e. England + Scotland + Wales only. Northern Ireland has a separate electricity grid.

2) “Ponton considers the case of a tripling of UK wind generation rated capacity, from the current 28 GW to 84 GW. Average usage is about 35 GW, and peak usage is about 45 GW”

The proposed increase in wind generation capacity is needed because enviros, eco-loons and politicians are attempting to switch the space-heating demand of the 80% of Britain’s homes currently met by natural gas, over to electricity. Natural gas supplies approx 3x the annual amount of energy supplied via non-gas generated electricity.

However, natural gas currently supplies approx 3.6x the peak daily demand and 4x the peak hourly demand vs electricity. In addition, Nat Gas currently supplies approx 7.6x the peak hourly difference in demand, and 7.3x the peak 3-hourly difference in demand vs electricity.

At our latitude, all our space-heating demand occurs in winter and the shoulder autumn/spring months. Precisely the period when electricity demand and prices are highest.

The net result is that even a doubling of annual energy demand would be compressed into the ~6 months of already-peak electricity demand.

Whilst storage offers an opportunity to time-shift supply, cold weather is un- time-shiftable.

Britain currently has 27GWh of pumped hydro storage plus less than 2GWh of batteries. If (but they don’t) they were capable of rapid discharge, they’d keep our grid ‘live’ for approx 40 minutes at 5pm on a cold winter weekday.

PS. We’ve ~40,000GWh of natural gas storage.

Reply to  Joe Public
April 5, 2023 8:02 am


It is absolutely necessary to have highly reliable electricity service, if we are forced by the government to “ELECTRIFY”, i.e., have heat pumps, and electric vehicles, and electric ovens.

Europe Learning an Expensive Wind/Solar Lesson: There was hot weather and plenty of sunshine, but little wind and little rain, i.e., a drought, in Europe, in 2021

As a result, there was plenty of solar electricity, but less than normal wind and hydro electricity 
Also, French nuclear plant output had to be curtailed, due to: 1) delaying proper maintenance, 2) strikes for higher wages, and 3) insufficient cooling water. France, instead of a major exporter, became an importer of electricity.

Europe, in addition to the scrounging around to replace Russian gas, also had to fire up all of its gas plants, and re-start some retired coal plants, and, in Germany, keep some nuclear plants running, to offset the unreliability of weather-dependent electricity, such as wind, solar, hydro, and even nuclear.

Wind and Solar are Deficient Electricity Sources: Wind and solar could not be fed to the NE grid, unless the traditional power plants were present to counteract their output variations, on a less than minute-by-minute basis, 24/7/365. That means, almost none of the traditional power plants, and their fuel supplies and fuel storage capacity, can be shutdown, if wind and solar become high percentages of the annual electricity load onto the NE grid.

It would be very prudent, to have a large capacity, MW, of coal, oil, and gas plants, that are staffed, with nearby fuel supplies and fuel storage capacity, kept in good working order, to be ready to operate, on demand, especially during:

1) Peak demand hours of late-afternoon/early-evening
2) Wind/solar lulls that could last 5 to 7 days, and could be followed by another multi-day wind/solar lull a few days later, before any battery systems could have been recharged!!

Wind systems generate electricity when the wind is blowing, but zero electricity when the air is still
Solar systems generate electricity when the sun is shining, especially around noontime, but generate less electricity when the sky is cloudy, and zero electricity when the sky is dark, or when panels are covered with snow and ice for several days.

As a result, wind and solar cannot function as dispatchable resources – meaning, they cannot be quickly deployed, on demand, such as during the peak-demand periods of late-afternoon/early-evening.

This article shows the wind/solar generation shortfall, and turnkey capital cost, due to a one-day wind/solar lull in New England
It also shows the electricity drawn from the high-voltage grid to enable grid-scale battery systems to counteract the one-day shortfall

Joe Public
Reply to  wilpost
April 5, 2023 10:58 am

“Europe Learning an Expensive Wind/Solar Lesson: There was hot weather and plenty of sunshine, but little wind and little rain, i.e., a drought, in Europe, in 2021

As a result, there was plenty of solar electricity ….”

The UK is “one of the darkest countries in the world” – according to the late Prof Sir David MacKay. Consequently, our million+ solar installations rated at 13GW generate at a pathetic 4% (or less) capacity factor in January, our month of greatest electricity demand.

Reply to  Joe Public
April 5, 2023 1:01 pm

You are right in general, but I was talking about 2021

Joe Public
Reply to  wilpost
April 5, 2023 1:47 pm

For 2021 as a whole, Britain’s entire fleet of solar installations generated at a mere 9.8% capacity factor.

Their monthly output is inversely proportional to our monthly demand. 😀

2021 Solar generation 4% of our energy mix 9.8% Capacity Factor.jpg
April 5, 2023 7:07 am

In theory, the 30%ish capacity factor of wind can be doubled or more to match the 60% to 80% cap factor of nuclear or fossil fuels.
However, it is becoming increasingly clear that overbuilding must occur – so more than 2 times more wind vs. nuclear/fossil fuels and closer to 4 times more.
As for curtailment: the problem isn’t overproduction of electricity per se. The problem is contracts and subsidies that mandate every kWh produced by wind or solar received both a minimum fixed payment even if unwanted and have priority in consumption by the grid. The latter is literally bass-ackwards; intermittents should be on the margin, not the core.

Reply to  c1ue
April 5, 2023 1:03 pm

Would adding intermittents on the margin, not the core, be an admission of defeat?.

April 5, 2023 8:30 am

Place people, flora, and fauna in sardine cans, and spread the Green blight through occupation.

April 5, 2023 10:07 am

“Renewables” might have reached a tricky part of the Technology Adoption curve.

“Innovators, Early Adopters, Early Majority, Late Majority and Laggards: These are the 5 groups that consumers can generally be divided in. Already in 1962, the sociologist Everett Rogers published the book ‘Diffusion of Innovations‘ in which he classified consumers in distinguished groups with different buying habits by synthesizing research from over 500 of diffusion studies. Today, the model is better known as the Technology Adoption Life Cycle and describes the adoption or acceptance of a new (technological) product or innovation, according to the demographic and psychological characteristics of these 5 distinguished adopter groups.”

Non-visionary, risk averse humans who worry (not always rationally) about what things cost versus what they do might stop renewables or might pull renewables into the mainstream. As always “we’ll see”. Based on survival bias, most things that exist succeeded.

AGW is Not Science
Reply to  KevinM
April 6, 2023 12:52 pm

You make it sound as if wind and solar are “emerging technologies” in the sense that they do something (a) never before conceived and/or (b) better than the technologies they propose to replace.

Both wind energy (windmills used to create mechanical energy) and solar (passive heating of stone or other materials) have been attempted/applied before. If the new tech of modern wind turbines and modern solar panels producing electricity was being compared with these methods of harnessing the wind and the Sun as energy sources, there would be little resistance to their adoption.

But comparing modern wind turbines and solar panels to coal, oil, gas or nuclear power plants is kind of like suggesting the “Technology Adoption Curve” be applied to the notion of replacing automobiles with donkeys.

April 5, 2023 11:55 am

Maybe if they use any excess power to pump water from the North Sea into the Irish Sea and then generate power from letting it flow back out at peak demand?

What? It makes just as much sense as spending enough money to re-insulate 100% of the houses in all of the B.I. on windmills to gift to the power company.

April 5, 2023 12:37 pm

The world community needs to choose a nation to use only wind and solar. My choice would be Australia, they are already enthusiastic about moving to wind and solar, they aren’t connected to another grid so there can be no cheating and we could refurbish the fossil fuel units while they are down. The deal is if Australia is successful we move forward with wind and solar. However when they fail and everyone knows they will, we put this renewable energy fiasco behind us. I want it to fail, I want people to hurt, it is the only way to put this mess behind us. Of course my experiment would never make it to total failure because even the least of us aren’t that stupid. But it needs to be done.

Reply to  Bob
April 5, 2023 1:02 pm

Australia needs a revolution to throw out the wind solar idiots

Reply to  wilpost
April 5, 2023 6:34 pm

That may be true I don’t know. What I do know is that we have to go all out and prove that wind and solar are not up to providing the energy needed when it is needed at an affordable price. If the wind and solar junkies were worth their salt they would jump at the chance to once and for all prove that they are right. But it is too soon taking advantage of the cash cow for them to risk it because they would lose big time.

AGW is Not Science
Reply to  wilpost
April 6, 2023 1:13 pm

As does every other “western” nation.

Reply to  Bob
April 6, 2023 7:40 pm

Recently printed in the Australian Financial Review; Six of Australia’s top CEO’s / executives held a round table meeting. This is a quote from the meeting;
Australia’s transition to net zero is going to cost us $5 trillion to $10 trillion dollars and it’s not going to follow a straightforward path.” Australia’s lame media response was nothing to see here, the plebs don’t need to know the cost.

Spending up to ten trillion dollars will turn the Australian economy into a 3rd world basket case. Can you please choose another country to be your crash test dummy?
To prove the transition, building a million to one scale model on a quarter acre block. It would be less financially painful when it fails and it will fail.

Nick Stokes
April 5, 2023 1:57 pm

The main problem identified by Ponton is the same one previously identified by Andrews and Gregory. Before you even get to the very high cost of storing electricity, there is another huge hurdle, which is that the availability of wind to generate electricity varies with a seasonal pattern.”

There is a basic failure of arithmetic in these analyses. The problem isn’t seasonal variability of wind. It is seasonal variability of demand, and all generation has the same problem.

The way it has always been solved is to provide sufficient generation capacity to meet the peaks. What Gregory and successors do is to fail to do that for wind. And so they say storage is needed to carry through the year, which of course leads to ridiculous numbers. Storage was meant to carry through windless periods, but not over a year.

As I showed here, if enough generation is provided to meet the peak, as is done for all other generation, the costs rapidly come down.

Frank from NoVA
Reply to  Nick Stokes
April 5, 2023 4:33 pm

‘The problem isn’t seasonal variability of wind. It is seasonal variability of demand, and all generation has the same problem.’

Well, I guess it’s our own fault for having built a system that could cheaply and reliably provide energy on demand.

old cocky
Reply to  Nick Stokes
April 5, 2023 5:11 pm

You only wound up with 4 – 6 hours of storage in that analysis.

Yes, it should be designed to meet peak demand rather than average, but it also needs sufficient storage to cover the longest low supply.period. That is in the order of days rather than hours.

Actually, I’ll amend that. It’s not peak demand, it’s worst-case demand-supply gap. Peak demand is during the day in summer, but the largest gap may well be winter nights,

Nick Stokes
Reply to  old cocky
April 5, 2023 5:48 pm

You only wound up with 4 – 6 hours of storage in that analysis.”

Well, that was for the whole USA48 (where the wind is usually blowing somewhere) and with a degree of overbuild. But that is how the arithmetic goes. If you build not enough capacity for the annual peak, storage costs are huge. But a small amount of overbuild brings storage costs way down, and is well worth it.

old cocky
Reply to  Nick Stokes
April 5, 2023 5:59 pm

I’m not arguing that there isn’t an optimal overbuild/storage mix, just that 6 hours of storage is at least an order of magnitude too low a margin.

Probabilistic approaches always run into problems if you don’t allow a sufficient spread, especially with asymmetric distributions.

Nick Stokes
Reply to  old cocky
April 5, 2023 6:07 pm

Yes, I agree. As I said in that analysis, it would have been enough for 2019, but you would want a margin for less favorable years.

old cocky
Reply to  Nick Stokes
April 5, 2023 6:34 pm

On a “wet finger in the air” basis, your H=10 (51 TWh storage) is probably close to the mark (5 days) as far as safety margin is concerned.

Another interesting exercise would be to add gas turbines back into the mix to cover extended low W&S.
Somewhere around 14 hours peak demand storage should cover 95%+ of low supply situations, depending on the W&S mix.

It’s not zero carbon [dioxide], but sometimes the perfect is the enemy of the good enough.

Nick Stokes
Reply to  old cocky
April 5, 2023 8:51 pm

Hydro has a role too. In Australia, say, it runs at about 7%. Even without pumping, reserving that for peaks would go a long way. It would need more generators installed to increase peak MW.

old cocky
Reply to  Nick Stokes
April 5, 2023 9:19 pm

I think you had some figures earlier which showed that Snowy Hydro has enough storage to supply the eastern states for around 16 hours if it could be pushed that hard. The flow rate may be a limiting factor, and the bulk of our dams are for irrigation or water supply.

It would certainly be interesting to calculate the potential generation rates of the existing dams.
The release rates of the dams and downstream non-flood capacities of their river systems would be a limiting factor.
Most of them only have limited fall available as well, because it’s flat downstream.

ps – found this list of Australian dams, etc.

Chaffey is upstream of Keepit, so might have potential for pumped storage hydro.
Nope, the confluence of the Peel and Namoi is just below Keepit, but Split Rock is upstream.

Nick Stokes
Reply to  old cocky
April 5, 2023 9:49 pm

I think Snowy capacity is higher than that. A rough calc says that Talbingo alone could supply the NEM for 15 hrs, if there were enough generators and you ran it dry. Snowy 2 claims to store 350 GWh, which is 17.5 hrs at 20 GW. But I think that is just the pumped storage capacity.

old cocky
Reply to  Nick Stokes
April 5, 2023 10:19 pm

Talbingo is around 200,000 ML. Blowering is 430,000 and Eucumbene is just over a million.

The 20 GW may be a catch – current Snowy Hydro generating capacity is 4GW. There is sure to be scope to increase it, but 20 is probably pushing it.

It looks like peak demand is around 32GW (, so even SH2’s 350 GWh is under 12 hours even if the generation rate could be bumped up. Even adding Tas hydro probably doesn’t give sufficient generation or storage capacity. Bummer 🙁

old cocky
Reply to  old cocky
April 5, 2023 10:02 pm

There’s all sorts of interesting info available –

Snowy Hydro currently has a potential output of around 4GW. but it was designed largely as a hydro-electricity system and has well over half of NSW’s water storage capacity – probably over 2/3.
That shows te rationale for Snowy Hydro 2.

Reply to  Nick Stokes
April 6, 2023 1:17 pm

Is there any lie so discredited, that Nick won’t repeat it?
In reality, there are times where there is no wind blowing at all, not for an area thousands of miles across. Nick also doesn’t consider the cost of building sufficient wind for every part of the country to be able to power the rest of the country all by itself. Nor the cost of providing the infrastructure needed to transport electricity of the thousands of miles between where the wind is blowing and the power is needed.

Nick Stokes
Reply to  MarkW
April 6, 2023 4:33 pm

I used the hourly data of Ken Gregory for 2019, USA48. Mean solar+wind was 40 GW. The hourly minimum for the year was 10 GW.

On transmission, China four years ago completed a 3293 km, 1100 kV, 12 GW DC line across China. It’s all possible.

It doesnot add up
Reply to  Nick Stokes
April 6, 2023 5:47 pm

DIfferent years can produce very different results. For a system to be viable it has to cater with the toughest years, not an average year or a favourable year. Forecasters don’t know when the next year with ultra low renewable output and/or lengthy spells of Dunkelflaute will occur. Neither do they have much handle on the consequences of extensive exploitation of wind, beyond some early modelling and data of the effects of building downwind of existing capacity. Assumptions that the next windfarms will be more productive than the last abound, but reality doesn’t seem to be turning out that way. We are also beginning to see the engineering limits on wind turbine dimensions because of the stresses caused by differential wind speed, tower shadow etc. which cause more frequent maintenance and parts replacement that make them less economic. This has long been a problem for designs for tidal stream turbines, where the much higher density of water, random turbulence from surface wave action and steep gradient of current velocities with depth have wrecked many a design, constraining them to small turbines that are economically very unattractive. Your assumption of a copper plate grid also results in a very significant underestimate of the required resources. It really is not practical to assume that windy weather in California can result in a surplus that can be transmitted across the continent to deal with icy still weather in Maine. If you want to supply so large an area your analysis must be geographic, and look at asset utilisation economics. It will make your numbers a whole lot uglier.

Nick Stokes
Reply to  It doesnot add up
April 6, 2023 10:58 pm

It really is not practical to assume that windy weather in California can result in a surplus that can be transmitted across the continent to deal with icy still weather in Maine.”

That is not assumed. It forgets the role of distributed storage. Maine would draw on storage; because it is a sub-region, the draw is not so great. Meanwhile power from Cal (overbuild) would travel East, helping other parts where the wind is down, and sparing storage for use where it is needed.

The key thing is that storage is only called on for calms. Gregory, Ponton etc were forcing it to cover for generation that was inadequate for the annual demand peak in average wind.

Joe Public
Reply to  Nick Stokes
April 7, 2023 1:25 pm

“The key thing is that storage is only called on for calms.”


How much of the much-lauded Hornsdale BSAB storage project 100MW/129MWh was available for market participation?

Only 30MW – because 70MW was reserved for grid stabilisation to overcome the destabilising effects of so much ….. wind capacity. What irony.

Likewise for many subsequent battery projects that are ‘sold’ to the masses for their storage capability, with little mention that most of their power capability is needed for stabilistion.

Hornsdale_Power_Reserve_penalised__900_000_for_inability_to_provide_contingency_services_as_offered___Australian_Energy_Regulator BSAB.jpg
Nick Stokes
Reply to  Joe Public
April 7, 2023 1:54 pm

Only 30MW – because 70MW was reserved for grid stabilisation to overcome the destabilising effects of so much ….. wind capacity. What irony.”

Yes, because the 70 MW made money (lots of it). The 30 MW didn’t, because SA for now does not need storage. It fires up the gas generators, or imports. The 30MW was actually used for arbitrage (buy low, sell high). It hasn’t been very profitable because the storage is limited and the occasions to sell high are not frequent enough.

Joe Public
Reply to  Nick Stokes
April 8, 2023 4:16 am

“Yes, because the 70 MW made money (lots of it). The 30 MW didn’t….”

Can you then explain why its commercial, profit-driven owners didn’t commit its entire 100MW to grid stabilisation in order to make even more money?

Poor South Australians – their electricity bills inflated to have to pay for the stabilisation that was previously provided free of charge by its gas generators. Gas generators that didn’t destabilise its grid as its wind capacity does, in the first place.

Nick Stokes
Reply to  Joe Public
April 8, 2023 2:52 pm

No, in fact SA exported stabilisation (and made money from it). It wasn’t so much the frequency control, but smoothing the transitions when generators switch on and off. That is a long standing problem, and batteries are a much better solution.

The Real Engineer
Reply to  old cocky
April 6, 2023 1:15 am

You have forgotten something as usual Nick. Ok your plan might work 90% of the time, the 10% where it doesn’t would scupper the US for days after the failure! It probably would be once a month on average. Then the idea of emptying a dam system in a few hours, how do you fill it up again, that would take weeks! Talk about lack of practicability.

old cocky
Reply to  The Real Engineer
April 6, 2023 5:16 pm

Was this a reply to Nick or to me?

Nick’s analysis of a particular year got away with around 6 hours storage, which seems rather optimistic.

The risk profiles of W&S need to be investigated thoroughly to determine the amount of storage required. We do 100-year and 1000-year flood risk assessments for building (well, we used to), so something is necessary for W&S.
Then it comes down to the level of acceptable risk, and how to recover from a complete system failure. The more difficult and time-consuming it is to recover, the lower the risk tolerance.
To use an analogy from my working life: I couldn’t care less about an individual user PC, but I put in a hell of a lot of effort to keep the mission-critical servers in the data centres available all the time, and to replace them without anybody noticing it had been done.

Reply to  old cocky
April 7, 2023 2:16 am

Its not worth arguing with. Anyone who is prepared to argue that the US can move to net zero by way of wind with 4-6 hours of storage isn’t worth the time. I’m giving up on Nick.

Its a classic advocacy of the impossible by someone who has no accountability for the outcome of his prescriptions.

Lets see a pilot somewhere if its so easy.

Nick Stokes
Reply to  michel
April 7, 2023 1:56 pm

 Anyone who is prepared to argue that the US can move to net zero by way of wind with 4-6 hours of storage “

Actually, I didn’t say that. That was Old Cocky, deriving it, I think, from the cases of high overbuild that I analysed.

old cocky
Reply to  Nick Stokes
April 7, 2023 2:38 pm

That was Old Cocky, deriving it, I think, from the cases of high overbuild that I analysed.

I just divided the storage by daily demand to provide some more context. I think the 4 hours was peak demand and 6 was average demand.
Most people’s eyes glaze over if they see equations or raw numbers, so it’s handy to convert to more immediately usable units.

It just happens that it worked out at such a low number for that particular year. Repeating the exercise for 10 years should give a better idea of the variability.

Joe Public
Reply to  Nick Stokes
April 6, 2023 5:35 am

1) “As I showed here, if enough generation is provided to meet the peak, as is done for all other generation, the costs rapidly come down.”

There is a basic failure of qualification in your claim.

That generation capacity needed to meet the peak must include sufficient dispatchable capacity.

Britain already has sufficient renewables capacity (>50GW) to exceed our recent actual peaks by 10%, but there’s never been an instant when fossil fuels weren’t needed to prevent blackouts. Often, their shortfall has been 90% of the then-current demand.

2) “Storage was meant to carry through windless periods ….”

Which for Britain can last a week or longer during our month of greatest electricity demand, and during which our entire fleet of 11,000 turbines generates at less than 10% capacity factor.

Reply to  Joe Public
April 7, 2023 7:24 am

Yes. This is of course the obvious point. But (and I apologize for having been critical in the past of people who have said what I am about to say) there are none so blind as those that will not see.

Reply to  Nick Stokes
April 6, 2023 1:14 pm

The problem is that the seasonal variability of wind and solar are out of phase with the seasonal variability of demand.
Of course the socialist solution is not to fix the problem with generation, it’s to require consumers to only use power when it is available.

Nick seems to think it is easy to just over build wind and solar sufficiently so that even when the sun isn’t shining and the wind is blowing, they can still produce enough power.

Reply to  MarkW
April 7, 2023 8:16 am

Yes, exactly the point. And you can see it very clearly in the charts here which give a graphical version of your point of the UK record:

Its very easy. You just use the historical archive to look at 2021 or 2022 in 90 day increments, and also annually. Nick says:

“The problem isn’t seasonal variability of wind. It is seasonal variability of demand, and all generation has the same problem.”

This is totally wrong.

As you say, in the case of wind, high demand, as you can see from the charts, often coincides in the UK with low wind output, and low demand with high wind output.

Its the unreliability of wind in any season that is the problem, and you will not solve that by overbuilding

Nick then goes on to say that “all generation has the same problem”. Of course it doesn’t! The whole point about a mixed coal or nuclear and gas grid is that its dispatchable. You turn on the gas to meet high peaks, whether seasonal or not is immaterial. And you keep them on as long as the peak lasts. You cannot do this with wind. The claim is straightforwardly dishonest.

The solution to unreliability is to think about it in a quite different way. You are not running wind supplemented by gas. You are running gas supplemented by wind. The question is whether such a system is more cost effective and reliable than running on gas and coal without any wind.

Does supplemental wind pay for itself? No-one has pointed to a fully costed case showing an example where it does.

Joe Public
Reply to  michel
April 7, 2023 1:43 pm

Thanks for the link to Energy Dashboard, Michel. 👍

Nick Stokes
Reply to  michel
April 7, 2023 4:02 pm

“This is totally wrong.
As you say, in the case of wind, high demand, as you can see from the charts, often coincides in the UK with low wind output, and low demand with high wind output.”

I was actually talking about the US. But looking at UK, here from the dashboard is the last year total generation (hence demand):

comment image

Demand peaks in winter. And here is wind+solar

comment image

Wind also peaks in the winter.

But anyway, it is the deficit (supply-demand) that counts. And you just have to provide enough generation to cope with the predictable annual peak, at least. As has always been done.

Joe Public
Reply to  Nick Stokes
April 8, 2023 4:23 am

“Demand peaks in winter.”

“Wind also peaks in the winter.”

Winter lasts over 12 weeks.

January is our month of greatest demand, and week-long lulls, when our entire fleet of turbines generate at less than 10% capacity factor, also occur in January.

Week 16-23 Jan 2017 GB
April 5, 2023 3:59 pm

I wish this article had taken the calculations ALL THE WAY TO THE FINISH LINE…

Add all the EV Energy demand at NetZero.

Add the Costs of Industrial Heat not provided by the Grid.

Add the Costs for Carbon-Free AVIATION FUEL That WE DON’T HAVE YET.

Add all the CO2 involved in BUILDING ALL THIS INFRASTRUCTURE (that will have to be offset to reach NetZero and THAT WILL BE EXPENSIVE).

Add all the Home conversion costs for heat pumps.

Add all the costs of home improvements to old buildings not compatible with Heat Pumps.

Add continuing costs for Wind Turbine and Solar Panel replacements…every 20-30 years.

Take a stab at calculating the costs of power back-up using Liquid Air Energy Storage (that uses technology we already have) and appears to be in “first place” in $/kWh of Storage.

Get a final total… then Divide the FINAL TOTAL by the population… and find a way to broadcast that $$ Total PER PERSON Cost to the Nations and the World.

The POPULATION has got to wake up to the impossible COSTS INVOLVED.

They’re REAL COSTS… and we’re sliding down that mountain slope to CRASH AND BURN when the bills come due.

……… AND THEN we can address the fact that CO2 Emissions will not even decline before 2100 no matter WHAT WE DO IN THE WEST… with India, China, Africa and SE Asia building Coal Generation rapidly…and with Russia, Saudi Arabia, Iran, and Indonesia PUMPING OIL that the BRICS NATIONS will be burning in their cheap cars the next 100 yesrs.


Elon Musk isn’t helping with this unfortunately… he won’t address the Power Storage $Costs comprehensively…AND WE’LL NEED TWITER… and Specifically Musk himself since HE cant be silenced…TO GET THIS DUSCUSSION MAINSTREAMED.

Else… we are doomed.

The Lying Globalists destroy us Economically and they win.

April 5, 2023 4:12 pm

Once you permit the first intermittent generator onto the grid, you are lock into higher grid power costs.

However there is a mix of overbuild of intermitents, base load generation and storage that can be settled on to minimise the cost. It is based on the cost of each element of the system.

A 100% intermittent/storage grid is possible for any network but it is not possible globally and its is not going to give the lowest cost power in any network apart from those now with 100% hydro and limited perched water like Norway.

Intermittents offer an economic solution to Norway’s perched water limitations.

Reply to  RickWill
April 6, 2023 1:21 pm

It’s not so much the addition of intermittent generators, it’s the requirement that the power created by them must be used first.

The Real Engineer
April 6, 2023 1:07 am

I am concerned that these large energy storage systems, particularly batteries are extremely dangerous should anything go wrong (a very likely scenario over years timescale). The enormous energy contained release over a period of even hours would be catastrophic, in a few seconds would be like an impossibly large hydrogen bomb. It would be extremely unwise to be even 100 miles away if something did happen, say a few shorted cells starting a fire. The protection needed to keep the assets safe would be huge, they would be an ideal terrorist target, or even some other enemy.

April 6, 2023 11:12 am

The True Environmentalists will go bonkers over even the Idea of more pumped storage. Here are some facts;

  • Lower Reservoir Dam is 135 feet high and 2,400 feet long, containing 4 million cubic yards of earth and rock fill.
  • Lower Reservoir consists of 555 surface acres and water level fluctuates 60 feet during operation.
  • Upper Reservoir Dam is 460 feet high and 2,200 feet long, containing 18 million cubic yards of earth and rock fill.
  • Upper Reservoir consists of 265 surface acres and the water level fluctuates 105 feet during operation.

Useless for recreational use, possibly usable for fishing but would increase costs of the facility by adding Traveling Fish Screens and their maintenance. The site was built in 1977 and that $4-Billion would easily be $10 to 20 Billion. EPA regs have been drastically changed.

Pumped storage is still the least costly but has drawbacks. There is a reservoir near Pulaski, NY, which my son almost got our Jeep stuck in the mud when the Siren sounded warning that water was coming down the creek.

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