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23 April 2015

Snow White and the Seven Dwaunderers

The annual PreWalkDaunder (PWD) has been held for over twenty years. In that time the average age of the Daunderers has risen inexorably. On last week’s Daunder we came across some wonderful signposts; the one snapped below the captures Phil’s and my enfeebled state of mind rather well.

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A southerly PWD was chosen for this year’s venue ~ the Chiltern Hills ~ home to Brakspears; a fine brewery, sadly gobbled up by an international brewing conglomerate. However, the beer is still excellent and so the Chilterns are still worth a trip. These hills are absolutely packed full of red kites; one random blast of a shotgun skywards is sure to bag you a brace to bolster provisions. Unfortunately not a single Daunderer had the presence of mind to bring one along.

If you click on any of the pictures below they will open up much larger in another window. They won’t be the pictures you expected but I think you will agree that ‘Tracy from Bolton’ is a far better sight than grubby, sweaty hikers.

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DAY ONE:

Young Morpeth wasn’t feeling too chipper and sadly had to withdraw prior to the event. We were lucky in that Margaret stepped into the breach to add a steadying influence. And here they all are, in their cleanest, freshest kit, prior to setting off. The foreground is composed of unexploded WWII German Bombs. If one of these blighters were to go off, we would be spared three days of pointless walking around in circles. My headache from the pub in Wallingford the previous night was not helped by staring into the blinding sunlight.

I suffer for my art.

SNOW WHITE & SIX DWAUNDERERS

SNOW WHITE AND THE SIX DWAUNDERERS

L-R: GERRY, MARGARET, ROBIN, JJ, LORD ELPUS, BOB, CROYDON. I’M THE HANDSOME CHAP TAKING THE PICTURE

 

And below you will see some immaculately presented examples of the TGO Challenge’s finest shelters.

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CROWMARSH GIFFORD CAMPSITE

We walked uphill. In fact, we walked quite a bit of uphill and there were mutterings of dissent in the ranks. This is all quite normal for a PWD and is assiduously ignored by the creator of the route. He’s old and couldn’t give a fig for those in his care. Sod the lot of them!

There wasn’t a cloud in the sky and so eight old and infirm Daunderers slip-slap-slopped themselves with gallons of midge repellent. After all, this was practice for Scotland.

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You will notice two purposeful Daunderers in the picture below. It is all an act; these two charlatans spent the rest of the walk lying on their backs, sobbing uncontrollably.

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DIDCOT POWER STATION, WITH A BIT OF SCENERY IN THE FOREGROUND. SEE IF YOU CAN SPOT THE TEN RED KITES.

 

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A PICTURE FOR ALAN RAYNER – A TRACTOR ENTHUSIAST.

Quite why this chap is ironing his fields with a roller escapes me; it’s far too hilly for cricket.

 

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The picture above worries me a great deal. We resemble a bunch of Ramblers. And as any fool knows, Ramblers are a bunch of old fogies who walk in gangs in crocodile formation. I think this was the ‘B’ Walk.

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There will be lots of pictures of this tree in the Daunderers’ photo albums, as everyone took a picture of it. Because of these thoughtless acts, that tree could well develop a complex, that in time could lead to phone calls to the Samaritans. It won’t get much help there if Lord Elpus has his way… But more on that later.

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Miraculously and with astonishing good fortune, the Rising Sun at Witheridge Hill materialised before our very eyes, just in time for a rather tasty luncheon and a few pints of Brakspears.

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THE SATISFIED SMILE OF A MAN WHO HAS JUST FARTED & THINKS NO ONE HAS NOTICED. MARGARET BEGS TO DISAGREE.

 

We strolled down the hill through the wonderfully plush outskirts of Henley. Northerners in the group nodded knowingly to each other; all these posh houses were owned by rich Bastard Bankers! Boo! Hiss!

After a tortured slog of some 13 miles or so in the burning heat of the Oxfordshire sunshine, an evening was spent in the Three Tuns in Henley Marketplace, drinking Brakspears, bedded down with Fish and Chips.

 

DAY TWO:

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Lord Elpus, slumped casually against a stile, (his legs had gone, after a stiff climb uphill) alone with his thoughts, musing on the previous nights shenanigans with Tracy from Bolton.

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In the picture above you will recognise two alcoholic Daunderers who had spotted a pub sign on their maps at the bottom of the footpath. The Landlord told them to sod off as it was another half an hour to opening time.

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A particularly sexist signpost. Someone should write to the Guardian about this and get these places assigned new names. Just after this spot, bang on time, our morning coffee-break was entertained by an aerobatic display provided by a biplane as we lay in the cool environs of an ancient church that is being restored.

 

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LORD ELPUS, LOOKING PLEASED WITH HIMSELF AS HE BELIEVES NO ONE HAS NOTICED HIS HORRENDOUSLY LOUD FART.

 

 

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It was noted that there were quite a lot of Very Rich People buried in the graveyard of this extremely attractive church. Even in death, eh? And then, quite by accident, the Crown Inn at Pishill arrived, just in time for a tasty soup and pint or so of Brakspears.

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HELPFUL PUBLIC SERVICE NOTICE IN THE CROWN INN GENTS.

It was another beautiful day, and the woods sang in the sunlight. It was as well, as otherwise Bob and Croydon would never have found us, as they had fallen from the back of the peloton. The singing trees guided them towards the pack.

Quite wonderfully, Margaret was concerned about these bums, and actually went back to try to find them! Lord Elpus and I exchanged a knowing glance. Left to us, the Red Kites would be picking over their sorry carcasses right now.

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Now would you believe it! After the team’s miraculous coming together another public house hove into view. Good Lord! They served Brakspears as well. There was a short shower (whilst we were warming our bottoms by the fireside), to dampen down the dust of the evening’s campsite.

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LORD ELPUS, TELLING MISS WHIPLASH ABOUT HIS NAUGHTINESS WITH TRACY FROM BOLTON. HE WILL REGRET THIS LATER.

 

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Statistically, there are far too many Ns on that signpost. I’ll leave that with you.

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A ROMANTIC SHOT OF DIDCOT POWER STATION, WITH SOME UNNECESSARY FOREGROUND CLUTTER.

 

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THE WHITE MARK: LOOK IT UP: IT’S A GREAT STORY [THAT’S A LINK – CLICK ON IT!]

 

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After over eleven of Her Madge’s Imperial Miles, the annual Pitch and Strike a Hike Tent Competition was held: Robin was the winner. (Fortunately for Robin, the Adjudicator ruled his own shelter out of the running.)

 

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Margaret astonished the Daunderers; finding the evening venue by employing the highly unusual tactic of asking a passer-by for the directions to the best pub in the village! The Chequers at Watlington. Brakspears and Brontosaurus Burgers.

It was at this point that Lord Elpus mused he could increase the happiness quotient of Great Britain ~ lifting it from the bottom of the European list of Happy Countries. All he had to do was volunteer to man the phones at the Samaritans. Yes, granted, the death rate would rise dramatically, but on the flip side, on average, Great Britain would be a far far happier place.

That’s that sorted then.

 

DAY THREE: 

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Red Kite pictures: Swarms of the things. I just don’t see it myself. What’s it all about eh? They’re multiplying like rabbits. Soon they’ll be worse than the Scottish Midge, and when these blighters bite you’ll know all about it. I tell you, it will end in tears.

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It was then but a short seven mile stroll back to the pub in Crowmarsh Gifford through leafy wooded paths and gentle Chiltern lanes, with just a few hundred Grundon Waste Disposal Lorries chucked in every now and then. But who’s counting?

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You’ll note that there are two Daunderers missing from the picture below, taken in the Beer Garden of the pub. Well, six out of eight’s not too bad an attrition rate, is it?

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It was a jolly fine PreWalkDaunder. Many thanks to the survivors.

08 April 2015

The Catch-22 of Energy Storage

Robin Evans kindly pointed me to a post of fundamental importance concerning renewables. If anyone ever tells you that wind or solar is the answer to our energy problem, just steer them to this post, because they are talking out of their arse.

This post has been reprinted in its entirety from HERE from the blog “Brave New Climate”.

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The Catch-22 of Energy Storage

Pick up a research paper on battery technology, fuel cells, energy storage technologies or any of the advanced materials science used in these fields, and you will likely find somewhere in the introductory paragraphs a throwaway line about its application to the storage of renewable energy.  Energy storage makes sense for enabling a transition away from fossil fuels to more intermittent sources like wind and solar, and the storage problem presents a meaningful challenge for chemists and materials scientists… Or does it?


Guest Post by John Morgan. John is Chief Scientist at a Sydney startup developing smart grid and grid scale energy storage technologies.  He is Adjunct Professor in the School of Electrical and Computer Engineering at RMIT, holds a PhD in Physical Chemistry, and is an experienced industrial R&D leader.  You can follow John on twitter at @JohnDPMorgan. First published in Chemistry in Australia.


Several recent analyses of the inputs to our energy systems indicate that, against expectations, energy storage cannot solve the problem of intermittency of wind or solar power.  Not for reasons of technical performance, cost, or storage capacity, but for something more intractable: there is not enough surplus energy left over after construction of the generators and the storage system to power our present civilization.

The problem is analysed in an important paper by Weißbach et al.1 in terms of energy returned on energy invested, or EROEI – the ratio of the energy produced over the life of a power plant to the energy that was required to build it.  It takes energy to make a power plant – to manufacture its components, mine the fuel, and so on.  The power plant needs to make at least this much energy to break even.  A break-even powerplant has an EROEI of 1.  But such a plant would pointless, as there is no energy surplus to do the useful things we use energy for.

There is a minimum EROEI, greater than 1, that is required for an energy source to be able to run society.  An energy system must produce a surplus large enough to sustain things like food production, hospitals, and universities to train the engineers to build the plant, transport, construction, and all the elements of the civilization in which it is embedded.

For countries like the US and Germany, Weißbach et al. estimate this minimum viable EROEI to be about 7.  An energy source with lower EROEI cannot sustain a society at those levels of complexity, structured along similar lines.  If we are to transform our energy system, in particular to one without climate impacts, we need to pay close attention to the EROEI of the end result.

The EROEI values for various electrical power plants are summarized in the figure.  The fossil fuel power sources we’re most accustomed to have a high EROEI of about 30, well above the minimum requirement.  Wind power at 16, and concentrating solar power (CSP, or solar thermal power) at 19, are lower, but the energy surplus is still sufficient, in principle, to sustain a developed industrial society.  Biomass, and solar photovoltaic (at least in Germany), however, cannot.  With an EROEI of only 3.9 and 3.5 respectively, these power sources cannot support with their energy alone both their own fabrication and the societal services we use energy for in a first world country.

Energy Returned on Invested, from Weißbach et al.,1 with and without energy storage (buffering).  CCGT is closed-cycle gas turbine.  PWR is a Pressurized Water (conventional nuclear) Reactor.  Energy sources must exceed the “economic threshold”, of about 7, to yield the surplus energy required to support an OECD level society.

Energy Returned on Invested, from Weißbach et al.,1 with and without energy storage (buffering).  CCGT is closed-cycle gas turbine.  PWR is a Pressurized Water (conventional nuclear) Reactor.  Energy sources must exceed the “economic threshold”, of about 7, to yield the surplus energy required to support an OECD level society.

These EROEI values are for energy directly delivered (the “unbuffered” values in the figure).  But things change if we need to store energy.  If we were to store energy in, say, batteries, we must invest energy in mining the materials and manufacturing those batteries.  So a larger energy investment is required, and the EROEI consequently drops.

Weißbach et al. calculated the EROEIs assuming pumped hydroelectric energy storage.  This is the least energy intensive storage technology.  The energy input is mostly earthmoving and construction.  It’s a conservative basis for the calculation; chemical storage systems requiring large quantities of refined specialty materials would be much more energy intensive.  Carbajales-Dale et al.2 cite data asserting batteries are about ten times more energy intensive than pumped hydro storage.

Adding storage greatly reduces the EROEI (the “buffered” values in the figure).  Wind “firmed” with storage, with an EROEI of 3.9, joins solar PV and biomass as an unviable energy source.  CSP becomes marginal (EROEI ~9) with pumped storage, so is probably not viable with molten salt thermal storage.  The EROEI of solar PV with pumped hydro storage drops to 1.6, barely above breakeven, and with battery storage is likely in energy deficit.

This is a rather unsettling conclusion if we are looking to renewable energy for a transition to a low carbon energy system: we cannot use energy storage to overcome the variability of solar and wind power.

In particular, we can’t use batteries or chemical energy storage systems, as they would lead to much worse figures than those presented by Weißbach et al.  Hydroelectricity is the only renewable power source that is unambiguously viable.  However, hydroelectric capacity is not readily scaled up as it is restricted by suitable geography, a constraint that also applies to pumped hydro storage.

This particular study does not stand alone.  Closer to home, Springer have just published a monograph, Energy in Australia,3which contains an extended discussion of energy systems with a particular focus on EROEI analysis, and draws similar conclusions to Weißbach.  Another study by a group at Stanford2 is more optimistic, ruling out storage for most forms of solar, but suggesting it is viable for wind.  However, this viability is judged only on achieving an energy surplus (EROEI>1), not sustaining society (EROEI~7), and excludes the round trip energy losses in storage, finite cycle life, and the energetic cost of replacement of storage.  Were these included, wind would certainly fall below the sustainability threshold.

It’s important to understand the nature of this EROEI limit.  This is not a question of inadequate storage capacity – we can’t just buy or make more storage to make it work.  It’s not a question of energy losses during charge and discharge, or the number of cycles a battery can deliver.  We can’t look to new materials or technological advances, because the limits at the leading edge are those of earthmoving and civil engineering.  The problem can’t be addressed through market support mechanisms, carbon pricing, or cost reductions.  This is a fundamental energetic limit that will likely only shift if we find less materially intensive methods for dam construction.

This is not to say wind and solar have no role to play.  They can expand within a fossil fuel system, reducing overall emissions.  But without storage the amount we can integrate in the grid is greatly limited by the stochastically variable output.  We could, perhaps, build out a generation of solar and wind and storage at high penetration.  But we would be doing so on an endowment of fossil fuel net energy, which is not sustainable.  Without storage, we could smooth out variability by building redundant generator capacity over large distances.  But the additional infrastructure also forces the EROEI down to unviable levels.  The best way to think about wind and solar is that they can reduce the emissions of fossil fuels, but they cannot eliminate them.  They offer mitigation, but not replacement.

Nor is this to say there is no value in energy storage.  Battery systems in electric vehicles clearly offer potential to reduce dependency on, and emissions from, oil (provided the energy is sourced from clean power).  Rooftop solar power combined with four hours of battery storage can usefully timeshift peak electricity demand,3 reducing the need for peaking power plants and grid expansion.  And battery technology advances make possible many of our recently indispensable consumer electronics.  But what storage can’t do is enable significant replacement of fossil fuels by renewable energy.

If we want to cut emissions and replace fossil fuels, it can be done, and the solution is to be found in the upper right of the figure.  France and Ontario, two modern, advanced societies, have all but eliminated fossil fuels from their electricity grids, which they have built from the high EROEI sources of hydroelectricity and nuclear power.  Ontario in particular recently burnt its last tonne of coal, and each jurisdiction uses just a few percent of gas fired power.  This is a proven path to a decarbonized electricity grid.

But the idea that advances in energy storage will enable renewable energy is a chimera – the Catch-22 is that in overcoming intermittency by adding storage, the net energy is reduced below the level required to sustain our present civilization.

BNC Postscript

When this article was published in CiA some readers had difficulty with the idea of a minimum societal EROI.  Why can’t we make do with any positive energy surplus, if we just build more plant?  Hall4 breaks it down with the example of oil:

Think of a society dependent upon one resource: its domestic oil. If the EROI for this oil was 1.1:1 then one could pump the oil out of the ground and look at it. If it were 1.2:1 you could also refine it and look at it, 1.3:1 also distribute it to where you want to use it but all you could do is look at it. Hall et al. 2008 examined the EROI required to actually run a truck and found that if the energy included was enough to build and maintain the truck and the roads and bridges required to use it, one would need at least a 3:1 EROI at the wellhead.

Now if you wanted to put something in the truck, say some grain, and deliver it, that would require an EROI of, say, 5:1 to grow the grain. If you wanted to include depreciation on the oil field worker, the refinery worker, the truck driver and the farmer you would need an EROI of say 7 or 8:1 to support their families. If the children were to be educated you would need perhaps 9 or 10:1, have health care 12:1, have arts in their life maybe 14:1, and so on. Obviously to have a modern civilization one needs not simply surplus energy but lots of it, and that requires either a high EROI or a massive source of moderate EROI fuels.

The point is illustrated in the EROI pyramid.4 (The blue values are published values: the yellow values are increasingly speculative.)

Finally, if you are interested in pumped hydro storage, a previous Brave New Climate article by Peter Lang covers the topic in detail, and the comment stream is an amazing resource on the operational characteristics and limits of this means of energy storage.

References

  1. Weißbach et al., Energy 52 (2013) 210. Preprint available here.
  2. Carbajales-Dale et al., Energy Environ. Sci. DOI: 10.1039/c3ee42125b
  3. Graham Palmer, Energy in Australia: Peak Oil, Solar Power, and Asia’s Economic Growth; Springer 2014.
  4. Pedro Prieto and Charles Hall, Spain’s Photovoltaic Revolution, Springer 2013.

03 April 2015

Wind threatens security of Scotland’s power supplies

  • NOTE: I have reproduced this article in its entirety from Scottish Energy News. It is of fundamental importance to the debate about wind energy in Scotland

 

Dash for Scottish renewables is creating an ‘economic cuckoo’ which threatens security of Scotland’s power supplies

Scientific Alliance Jack Ponton power chart graphic Feb 2015

By Prof. JACK PONTON and JOHN WILLIAMS

By 2020, Scotland will be generating a huge surplus of heavily subsidised renewable electricity that it cannot use, sell or store.

The cost implications of producing this surplus will run into billions of pounds, and experts are now demanding that the Scottish Government confirms how it will deal with this huge green surplus – just as Scotland’s cheapest source of electricity – Longannet coal-fired power station, faces closure.

This crisis has been widely predicted. It is entirely a consequence of reducing Scotland’s ability to balance electricity demand by rapidly increasing the variable supply from wind generated power. Wind power is intermittent, it is not secure, and it cannot be stored in the quantities required.

Given the Scottish Government’s renewable energy policy, the crisis is, ironically, a double one of shortages and (very costly) surpluses. 

At times, there will be a shortage of supply that could lead to power cuts, unless power is imported from England (in 2014, Scotland imported electricity from England on 162 days ).

At others, there will be an excess of production that cannot be used but will have to be paid for by consumers or taxpayers. 

In 2010, Scotland had a secure and balanced electricity supply.

There were two nuclear, two coal and one gas-fired power stations, a suite of hydro electric stations providing dispatchable, ie available on demand, power of about 8.4GW. There was a nominal wind capacity of just over 2.5GW.  The red line shows approximate peak demand of 6GW. Scotland’s electricity needs were safe and secure.

Even the loss of a major power station for maintenance or emergency repairs would not have required import of power from south of the border.

By 2015, a major transformation has taken place: the system is still secure but perhaps only just: the lights are still on – but it is costing more.

Cockenzie coal-fired station had been closed. Although Peterhead gas power station now has a reduced capacity there is still 6.7GW of dispatchable power, comfortably in excess of peak demand but susceptible to a nuclear outage.

The transformation has been in the expansion of wind to 7.1GW nominal capacity. Flexible dispatchable power, ie coal, gas and hydro, totals 4.7GW. (Nuclear cannot be conveniently turned on and off so, although it is dispatchable, it is not flexible.)

When the wind blows hard, there is still conventionally generated power to take off line, and the capacity to export up to 3.3GW via interconnection to England.  In 2010, there was 8.6GW of generating capacity; today there is a theoretical 13.9 GW capacity.

However, potential problems are beginning to emerge. Minimum wind load factors of less than 5% can occur so that wind generation can be lower than 0.35GW. For instance, at 2.30pm on 19 January 2015, UK wind load factor was 2.2%) If low wind generation coincides with a reduction in dispatchable generation, power has to be imported. Indeed, imports of power have been required on 162 days in the last three years.

Conversely, high wind speeds resulting in load factors of more than 80%, have at times of low demand required output reductions from Longannet – now the only major Scottish energy resource that can be turned down relatively easily. This increases the cost of operating the plant, and along with other factors such as carbon taxes has brought its future into question. 

Wind turbines may also need to be shut down to avoid overloading the grid, in which case their operators receive ‘constraint payments’ well in excess of their lost revenue.

What will be the position in 2020? Will Scotland benefit from the green electricity ‘bonanza’?

Or will the renewables’ surplus become an unbearable cost to the Scottish economy?

The 2020 configuration assumes that already consented wind farms totaling 8.68GW will have been built, exceeding the Scottish Government’s ‘100% renewable generation’ by nearly 20%.

It is likely that Longannet will have become unprofitable and will close down.  The two Scottish nuclear plants (owned by the French nationalised operator, EDF) should still be operational.There will be 4.4GW of dispatchable power, 1.6GW below the safe threshold. Although the 15.8GW of wind capacity operating above 10% capacity should cover that for most of the time, when load factors fall below this significant shortfalls will occur.

These will have to be met by importing dispatchable power from England, assuming that adequate capacity does in fact exist there. The 2.07GW of nuclear power should provide reliable base load regardless of the weather.

However, when one of these nuclear plants is off line for scheduled or unscheduled maintenance, Scotland’s security of supply will become entirely dependent upon imports.

This is one aspect of the problem that an unbalanced electricity supply will produce. The other, ironically, is what to do with a surplus of power.

Peak demand is at around 6pm on a week day in winter, and minimum demand is always at night at the weekend in summer. This minimum is about 38% of peak, roughly 2.3GW.  Night-time summer demand for electricity would be almost met by the two Scottish nuclear power stations, neither of which can be turned down easily.

With approximately 15GW of installed wind capacity operating at a realistic maximum of 80% load factor, wind generation could peak at 12GW, nearly all of it surplus to Scotland’s needs. 

Since producers get paid their elevated guaranteed price regardless of whether or not there is demand for the power, this represents a substantial cost to consumers – unless the surplus can be used effectively.

Interconnection capacity to England is to be increased to 6GW (at great cost), but this is only about half of the possible excess. 

The current Scottish Government plan is evidently for Scotland to somehow profit from exporting its surpluses. However, when the wind blows hard here it is usually also blowing hard in England and Europe, and consequently spot power prices hit rock bottom.

As it is extremely unlikely that Scotland’s neighbours would be prepared to pay the premium prices which the wind generators have been guaranteed, the cost of the difference will fall on local consumers.

Renewable energy enthusiasts talk about storing electricity but currently the only available means of large scale storage is pumped hydro.

There are two such schemes in Scotland and two in Wales. These have a storage capacity of only 27GWh, just over three quarters of an hour of UK average demand. The new Coire Glas scheme, approved but awaiting a final investment decision, is the only addition currently proposed. This would have a storage capacity of 30GWh.  Average daily electricity consumption in Scotland is about 100GWh. 

Peak excess production over a very windy 24 hours could be nearly 300GWh but Coire Glas could only handle 0.6GW. To absorb 12GW of excess generation would require at least 20 schemes of this size – but the geography and hydrology of such projects is so restrictive that it is not clear if there are any further suitable sites in the country, let alone 20.

How long will it be before the Scottish Government finally acknowledges the truth: that the blind dash for wind is pointless, it will be hugely expensive, and that degrading even more of Scotland’s landscapes will be futile?

Not only is there no need for any more wind in Scotland’s energy mix but the country’s lack of conventional supply will ensure long-term reliance on the UK and Europe for the safety of Scotland’s electricity supply.

Jack Ponton, FREng

John Williams is Chairman of the Borders Network of Conservation Groups.

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