Poles and trenches

Tweet An issue much troubling many people in this part of the world at the moment is the proposal for an overhead line to connect the Brechfa wind farms to the National Grid.  The final line is yet to be identified, but some broad corridors have been painted on maps as a basis for consultation.

As owners of land (to wit, a house and garden) which sits squarely in the centre of one of these corridors, we were invited to a session organised by Western Power Distribution recently for them to explain the proposals.  Whilst it was helpful to see the lines on a larger scale map, there really wasn’t a lot to be said.

To be honest I’m not particularly exercised either way about the prospect of a few extra telegraph poles with wires strung between them crossing the field in front of the house, and I don’t really understand the demand from some quarters for the entire route to be placed underground.  It would be visually better of course, and perhaps in some sections of the route which are particularly sensitive scenically it’s worth doing that.  But the disruption of digging a deep trench through the area is not to be lightly dismissed either.

Some of the opposition seems to be more about fighting yesterday’s battles rather than about the line itself; a sort of rear-guard action against the wind farms.  Making it impossible to connect them to the grid would certainly undermine the rationale for building them, but it’s a false hope and a misplaced campaign.

Some of the political opposition is less than honest as well; politicians who claim to be in favour of renewable energy and against fuel poverty doing their best to block renewable energy projects and increase the cost of the energy from those which are approved.

And there’s no small dishonesty either in the claims being made by some that putting the cables underground would cost no more than putting them overhead.  I don’t know who’s doing their sums or where they get their figures.  Western Power Distribution claim that the costs are £150,000 per kilometre for an overhead line and £986,000 per kilometre for an underground cable - six times as much.  It’s possible – of course – that they’ve exaggerated the difference a little, but the difference doesn’t go away just by asserting that it doesn’t exist.  And it isn’t just the installation cost which is different; digging up cables for repairs and renewal costs more than patching any overhead line.

Would I prefer that overhead lines never intruded on the view, anywhere?  Yes, naturally.  I want a nice clear view with no poles and wires.  But I also want affordable electricity when I need it, and I want it from renewable sources.  We can’t always have everything we want.

The answer is still blowing in the wind

Tweet This report a couple of weeks ago demonstrated:

a) that using wind energy leads to significant carbon savings, and

b) that use of wind energy at a level of up to around 20% of the UK’s electricity needs poses no threat to security and reliability of supply.

Neither of these conclusions will come as any surprise to those of us who support the inclusion of wind as part of the overall energy mix.  And I suspect that neither will be believed by those who oppose wind energy and prefer unsubstantiated assertions to the contrary. 

Indeed one reaction which I saw to the report in the letters column of the Western mail simply dismissed the report on the basis that it was written by individuals who had a vested interest.  Now clearly, having a vested interest in the outcome of a particular proposition means that one should read very carefully what people have to say on the subject, but it is not enough in itself to dismiss a report with which one disagrees.

Part of the problem in reconciling opposing views is the difficulty in putting precise figures on some aspects of the calculation.  The report itself can only estimate the CO2 savings, and provides a clear explanation of why that is so.  (And in fact, that makes it no different from many other areas of policy; it is invariably the case that while some things can be precisely measured, others always have to be estimated.)  I don’t doubt that the lack of precision will be seen as a cloak from behind which the naysayers will continue to use words such as “useless”.

On a related note, one anti-wind letter writer to the Carmarthen Journal last week came up with a “solution” to our electricity needs which avoids the use of wind energy completely.  He said that we should use electricity to produce steam to generate electricity, and that

"… a water screw producing enough electricity for just a few thousand homes can instead be used to produce enough steam to turn turbines which produce electricity for tens if not hundreds of thousands of homes ...”

In essence, his argument seems to be that small amounts of electricity can be used to generate steam, but that steam can then generate 10 or even 100 times as much electricity as was used to generate the steam in the first place.

If that were true, it would be a simple and elegant solution to the world’s energy needs.  Indeed, by simply repeating the process several times over, a small mountain stream in mid Wales could meet the entire world demand for energy.  Which sort of exposes the basic fallacy in the argument.  Unfortunately, power to amend the first law of thermodynamics has not yet been devolved to Westminster, let alone to Cardiff.

Gwynt y Môr

Tweet MH at Syniadau has already done a mathematical demolition job on the anti-wind campaigners referred to in this story.  I won’t repeat that analysis, with which I agree.  The reportage disappointed me somewhat, however.  Whilst it (I assume accurately) reported the claims and counter claims of the two sides, there was something of a lack of analysis as to whether either or both were right, and very little light generated as a result.

Truth can sometimes be an elusive concept, but in this case, it seems to me that it’s possible for both sides to be right.  However, they’re not talking about the same thing, and therefore one side being right about one thing does nothing to prove the other wrong about something quite different.

One of the arguments about wind is its predictability (or rather lack thereof).  But it isn’t quite as simple as that – wind is quite predictable in the very short term and in the long term; it’s in between that it becomes unpredictable.  Ask a meteorologist what the wind is going to do in the next hour or two, and (s)he will give you a pretty accurate prediction.  Ask how much wind we’ll get over a year, and you’ll get another pretty accurate prediction.  But ask what the wind speed and direction will be at 2.30 on the afternoon of Tuesday 4^th September, and you’ll be lucky to get any sort of prediction at all.

The overall predictability of the UK’s wind and weather means that it is perfectly possible to predict with a high degree of confidence how many kwh of electricity can be generated by any wind turbine over a year.  And whilst one may quibble with the detail of the mathematics (see MH’s post), converting that into a proportion of Wales’ total annual need, or even a number of homes whose needs can be met, is just simple arithmetic.  So the claim put forward by those behind Gwynt y Môr is entirely reasonable.

The counter claim by the opponents is based on the proposition that the energy produced may not be available at the time required by those households, and at other times electricity will be produced which those households cannot use.  It means that at times of surplus, the electricity produced will be used elsewhere, and at times of deficit, those households will be using electricity produced from other sources.  So, the argument goes, those households cannot rely on Gwynt y Môr to supply their needs.

That’s also true, but the proposition it demolishes isn’t the one being made; it’s something completely different.  And it certainly doesn’t support the conclusion that wind is therefore a useless source of energy.

Given the starting point of this post, I’ve only referred to wind, but we can actually generalise from that.  Any type of electricity generation based entirely on (free, unlimited) natural renewables (whether wind, tidal, solar, hydro or whatever) will never be able to match the certainty of availability when required which can be obtained from a power station fed by (expensive and depletable) fuels. 

That isn’t an argument for sticking with fossil fuels, nor for rejecting the use of renewables; it's just a feature of a different apporach to energy policy.  What it tells us is that, if we want to use emission-free renewables, we have to think in different ways about our electricity supply and distribution infrastructure.  Up to a certain percentage – as I recall, National Grid figures suggest that to be around 20% – the impact on security of supply is fairly minimal and can be coped with more or less within existing backup and contingency arrangements.  Beyond that, we will undoubtedly need to look at ‘storage’ facilities.  In addition to that, grid interlinks which spread the risk over a wider area are already being built.

We can’t – and no-one is suggesting that we can – rely on wind for all our electricity needs, but we can and should use it as part of the overall mix.

Green armies

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If there’s one aspect of human activity which I’d never describe as being in any way environmentally sound, it has to be warfare.  Using the earth’s resources to build weapons to kill, maim, and destroy is never going to be on anyone’s top ten list of sustainable activities.  So I was fascinated to read at the weekend that the army is ‘going green’.

It seems that they’re planning to install solar panels and wind turbines at bases in Afghanistan, and have been testing such an installation in Cyprus.  The plan is to deploy the new equipment later this year, and that it will slash fuel consumption by 45%.

However, lest anyone should think that the army is going soft, a member of the test team made it clear that this plan was all about saving lives, and had nothing to do with “tree hugging”.  The problem to which this is a response is really nothing to do with the environment at all – it’s just that the efforts to pacify that country have been so unsuccessful that fuel convoys are being regularly attacked by the Taliban.  The equation is a simple one: fewer convoys = fewer attacks = fewer deaths.

Now of course we should commend the army for reducing fuel usage, and for doing anything and everything it can to cut the loss of life in Afghanistan.  But we should not pretend that it has anything to do with environmentalism.  The only ‘green’ warfare is no warfare.