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Hiatus

I think I may put this blog on hold for a while.It’s been an interesting experiment and I’m glad I brought it this far: I feel as though I gave it a good run. Although obviously you need to do more than 7 months if you want to genuinely build popularity. Still, I only have a limited amount of free time, and it turns out that these posts aren’t really the way I want to spend my time at the moment.

I wish someone else was doing something similar so I could point you there. Perhaps Scottish Renewables, which have syndicated a fair number of these posts? It’s not a technical perspective, though, and that’s what I felt I could contribute.

Hopefully I’ll return to this in time when the propaganda and politics gets me irritated again!

So, today’s ministerial statement from the Department of Energy and Climate Change (available here has confirmed that the subsidy available for onshore wind farms will drop by 10%.

Now, while I work in the wind industry, my expertise is on the measurement and analysis of the wind itself rather than the funding mechanisms used to support it. In their coverage, BBC News are grudgingly positive about this, and the tone of their article matches pretty closely my own appraisal of this. It is good that the funding has not been slashed 25% as was previously suggested as that would be a very steep climb in a very short time and such things tend to have strong impacts. I have far less concerns about a 90% subsidy.

The UK’s system for subsidising renewable electricity generation for large-scale projects is based on a ROC: a Renewables Obligations Certificate. This is an unusual scheme internationally, where the more common form is a simple feed-in tariff which pays a bit extra for every kilowatt hour from a particular source.

ROCs are distributed based on generated energy, and different sorts of generation earn different amounts; the amount of ROCs earned is loosely tied into how mature the technology is. The “renewable obligation” referred to in the title requires suppliers to generate a proportion of their electricity by means of renewables, a proportion which then increases year on year. Suppliers then have to present their ROCs as evidence that they have met their legal commitment. However, the certificates are not tied to the supplier themselves, but can be traded with other suppliers. While my understanding of the whole process is pretty sketchy it actually seems quite ingenious because of course from a government perspective they don’t care if individual suppliers meet an arbitrary percentage target: they care that the country as a whole meets that target.

Today’s announcement says that onshore wind will no longer earn one ROC but instead will earn 0.9 ROCs.

I first heard this suggested a few months ago, and I was rather surprised at the idea that the number of ROCs would drop below 1. (Which demonstrates my failing to pay attention as other technologies have earned less than 1 ROC per MWh before now.) After all, what is the certificate supposed to be saying? The whole point of the system was not so much to support emerging technology (although they worked that in), but rather to incentivise electricity suppliers to support the UK’s legally binding targets to reduce our CO2 emissions. I therefore assumed, wrongly as it turns out, that a non-thermal plant with no direct CO2 produced during operation would not earn less that one full certificate per megawatt hour, representing 100% renewable electricity.

The way the system is set up, there are knock-on effects from reducing the ROCs earned by onshore wind, above and beyond the financial implications (and my feeling is that the technology is now mature enough to weather this small loss of subsidy). Energy generated from onshore wind will now count less towards a supplier’s renewables obligation than their generated output would suggest. But the targets remain legally binding.

The reduction in subsidy is partially justified in the ministerial statement with the followeing text:

…delivering the best possible deal for consumers has been at the heart of the RO banding review. In considering the final shape of the banding package, we have focused on the need to balance cost-effectiveness with the range of objectives that the RO must deliver.

Any gap between current generation and the legal target, this year or in the years ahead as the target increases, will have to be met by some form of generation if we are to meet our legally binding targets. It may be more wind farms, or companies may risk more on offshore wind or emerging marine technology: all of which are more expensive than onshore wind and which will cost the consumer more in subsidies.

I think it is probably right, all in all, that the subsidy for onshore wind should decrease. I’m very interested to see how it plays out from here though.

Every so often a company gets it so wrong you just have to sit back and enjoy the show. And laugh.

I give you Shell’s Arctic campaign.


Edited to add:

Well, it did always look a bit unbelievable that a company would get things so wrong on such a sensitive ground. Looking back, another red flag was that all of the posters, rather than just a majority of them, were green-type protests. Seems like the campaign was a Greenpeace stunt all along.

I discovered this through this New Statesman piece, which has the tag-line “Since when were Greenpeace the bad guys?” Um, I work in wind farms, and I’ve always been suspicious about Greenpeace: not just their tactics, which are often dubious, but their targets as well. But that’s perhaps an article for another time. More philosophically, there’s no such thing as bad people; just people who sometimes do bad things.

Busy busy

Work — in general, I think, not just with wind farms — comes and goes in peaks and troughs. You get quiet weeks, where you can just putter on doing whatever it is you do. Sometimes you get almost to the end of your to-do list and wonder what you’ll do then! This week is not one of those weeks; not for me, anyway. I’ve been out at meetings a day and a half, this week, I’ve got management visiting from Down South, and New Starts needing training and support, and on top of all this I’ve got a list of things to Sort Out and three ongoing analysis tasks.

I come home pretty tired with all that, and I don’t have a lot of spare energy for blogging or twittering at present.

Still, I do keep thinking one thing, and that’s about our approach to choosing a career. When I was at school, they asked what subjects you liked and were best at and then advised accordingly. Like English? Try teaching or writing. Chemistry? Become a forensic scientist. I am increasingly starting to feel that a better approach would be to ask what sort of tasks would make up a typical day, and work from there. Want independence? Freelance writing, or run your own business. Like solving problems? Engineering or science. Want an office job? Get good computer skills. Want to work outdoors? How about environmental science, zoo-keeping, gardening or building?

I’ve often wondered if that’s a better way to choose a career.

Wind farms are still fairly new technology. In resource assessment, you see this when you look back at the sort of analysis that was done about 5-10 years ago, on older wind farms. To generalise, at the beginning of our industry we greatly underestimated the variability and complexity of the wind. This mostly resulted in an overestimation of the yield.

Differences compared to current best practice include having too few masts; making masts too small and then vertically extrapolating the wind flow to hub height; underestimating uncertainty on the whole procedure and the output prediction; a lack of understanding on how the landscape features would interact with the turbines.

The trouble is that this means that the wind farms which have been designed according to current best practice are pretty new. If it takes 4-5 years to get a wind farm from the stage of measuring the wind through all the technical and non-technical surveys, calculations and checks that have to be done and then through construction, then the best practice of 4 years ago is only just becoming operational. This makes it challenging to compare the actual output with the prediction and thus demonstrate that the current best practice works.

Of course, there are improvements that can be made, and there are several interesting developments of the last few years which are feeding back into best practice.

  • Lidar technology: This is based on radar technology and can measure wind speed using a laser pulse rather than a physical device actually sitting in the wind. That means you can put a lidar on the ground and measure up to 200m up (some models go further than this). While this technology has been around for decades and has been used in the wind industry for at least five years, it’s only relatively recently that the wind industry has really taken the opportunities this presents to heart. The reason for this, to my mind, is about understanding. Lidar measures the wind in a completely different way, averaging over a large area rather than at a tiny point the way previous anemometer technology did. This is a very fundamental difference on what the data are telling you, and frankly none of our tools really understand how to make best use of this. The difference gets most notable as the terrain gets more complicated — so hills and forestry; both of which are often found near proposed wind farms.
  • Computation Fluid Dynamics. Lay English considers a “fluid” to be a synonym for “liquid” but in fact gases are also fluid and therefore the movement of air is best described by fluid dynamics. Computational fluid dynamics or CFD is a way to solve the predictions for the movement of air in an environment which takes in as much information as we can manage about the complexity of the real world. This has become much more important with the rise of offshore, where, we discovered, the wakes of wind turbines behave very much differently than they do on land. Previous models, which were extrapolation and approximation to limit computing time (and which, I should add, do fairly well most of the time and are still both relevant and extensively used), couldn’t provide a reasonable approximation of wind farm wakes offshore. I don’t think CFD is being used much onshore at present, but given how complex the newest wind farms are it won’t surprise me if we begin to see CFD models being performed more often for onshore sites over the next few years.
  • Models: Virtual Met Masts created by meteorologists seem to be very popular at present. These use large scale climate measurements, such as satellite data, to feed into local models and provide detailed predictions of various aspects of the local climate such as wind speed and direction. What I’ve seen of these has been very positive, generally these predictions align well with mast measurements. Still, no scientist worth their salt would ever suggest that real world data could be removed in favour of model outputs: especially with weather and climate the world is complex and the only way to really see what happens out there is to be there measuring it. Where these models come into their own is in trying to establish what the long term climate is like. Anemometers degrade over time, and the landscape itself changes around a mast which has been there for decades. These two facts mean it’s hard to get long term wind measurements with the sort of accuracy the wind industry demands that can give confidence in how the wind at a particular site is likely to be over the lifetime of a proposed wind farm. Models have the potential to be perhaps more consistent.

I suspect that when we look back in five or ten years on the industry now we’ll still see it as a teething period when a lot of initial problems in analysis, measurement, modelling and prediction, let alone actually operating large scale wind farms, still had to be resolved. I don’t know which of these technologies, or perhaps something else entirely, will become the normal face of wind analysis in ten years time. And I find that uncertainty rather exciting.

I found this article interesting: Women And Clean Energy: Overcoming The Double Standard.

I don’t know if it’s just that I care more about renewables, but I have been gaining the impression that renewables are held to far higher standards than any of their more established competitors. This holds for planning constraints imposed (met masts often have “bird diverters” attached, but I’ve yet to see them on a telecoms mast), and it certainly holds for the press coverage. The “women must be twice as good as a man to be thought half as good” idea does seem to fit this reasonably well.

But it is true that in both cases it’s a subjective thing which is being measured, so it’s harder to demonstrate an effect. I don’t know of any research done into the public dialogue for wind, nor of any comparisons of the planning procedure for wind farms compared to other technologies. Still it was interesting that someone else, in the US at least, has a similar impression.

I don’t know if you care greatly, but the gender balance in wind resource assessment isn’t too bad in my experience in Scotland: I’d say women have made up about 30-40% of analysts. Engineering teams and people working on operational wind farms still seem to be overwhelmingly male though.

Firstly, I’d like to draw your attention to the following blog on the Guardian’s site: Why there’s only one honest objection to wind farms.

I have been forming much the same opinion over the last few years. Sure, there are a few that sound like good objections until you give them any sort of thought:

  • health impacts have never been proven at any sort of scale and what studies have been done are generally low statistics, self-reported or otherwise flawed. I’m not discounting the fact that psychosomatic effects are very powerful, but it’s simply not logical to hold a particular industry or technology to account for psychosomatic effects, however powerful.
  • government subsidies go to all forms of power generation in one guise or another. Besides, you only get subsidised for power generated which gives a powerful incentive to take great care in your developments and particularly in your initial spend. You don’t get subsidies to build wind farms; that risk is the developers’ and the banks’ own. The big driver of rising fuel bills has been gas prices, not renewables.
  • paying sums of money to the already rich land owners — well there you have an issue with capitalism, not with wind farms. I’m not disagreeing that it’s better to give money to the poor than the rich, who would? But that’s the system we’ve got and wind developers have no greater moral responsibility to tackle unfairness than anyone else.
  • intermittant, unpredictable, small scale. Turns out wind farms, and the wind, are predictable enough; they are also highly responsive and can be quickly shut down or curtailed (run at reduced power) if necessary. They can’t provide more energy if the wind isn’t there, but they’re a powerful tool for the grid when it comes to balancing supply and demand.
  • carbon cost of building and land space. There’s a carbon cost to all building projects but an airport, for instance, takes up a lot of land and then creates pollutants. Wind farms later reduce carbon output. And while they do take up a lot of land if you look at the boundary, in fact most of the land remains available for crops and livestock as normal.
  • noise and shadow flicker. Shadow flicker is known to be a hazard to health in some cases, but only at high frequencies, far higher than large wind turbines get to even at high wind speeds. Because the sun follows a predictable path, it’s easy to demonstrate when it will happen and where and to be honest it’s pretty rare. It’s also easily reduced by closing curtains during the appropriate time of year, or facing a different direction. Since I live and work in the city I find it hard to take the noise complaints seriously as a mass issue (rather than on the level of individual nuisance): at high wind speeds the wind itself is louder if you’re outside or near a forest. Most of the time the noise of a working wind farm even actually inside its borders, isn’t much more than a medium-busy road, and we’ve learned to all but tune out road noise.

There are others, obviously, but none that I can think of which aren’t similarly easily rebutted.

I don’t think the author of the blog intends to suggest that people who object to wind farms and quote other reasons than looks are actively lying, just that they’re failing to acknowledge that they give disproportionate weight to minor issues because ultimately they don’t like 1) wind farms themselves or 2) their position in our landscapes.

Confirmation bias is a known phenomenon where we hear what we want to hear and discard evidence which contradicts our own preferences. I am aware of this, and I do make a conscious effort not to apply it to wind farms. The evidence I’ve seen for any of the objections up to now has generally been poor and even with a genuine effort to keep an open mind it hasn’t raised any real concerns.

I do worry about the number of people who are willing to argue “Wind farms are pointless: we should be investing in tidal farms!” or championing some other form of technology. We are investing money in researching tidal farms, and wave generation, and offshore wind farms, and even nuclear fusion, and these things are, indeed, very important to our future supply. But none of these technologies can generate the electricity we need now. They’re still in the pipeline. Wind farms can, and are. If, in ten, or twenty, or fifty years, wave or tidal becomes a significant contributer to our electricity networks, it will be built on lessons learned through onshore wind farms on how to cope with variable supply, and with supply that relies on weather conditions. Stopping the development of onshore wind farms would make it harder, not easier, for wave and tidal to reach deployment scale.

Apologies for my lack of presence on twitter at the moment, I’m really pushed for time with one thing and another and it’s only my one-post-per-week New Year’s Resolution that’s keeping the blog going.

Wind farm layouts

Wind farm layouts are pretty controversial. The bare fact is that putting turbines in the most lucrative positions which catch the most wind generally means putting them on top of hills. Which makes them visible for miles around.

There’s not really much that can be done about this conflict.

Besides, developers of wind farms don’t, as a general rule, actually buy the land they’re building on. Usually they rent it under contract from the landowner. And although the area of the wind farm is usually large, there’s usually a fair bit of spare ground around the turbines which can continue to be used for livestock or crops. In Scotland, we have laws protecting the right to access land; this means that if you want to go mountain biking at an operational wind farm the law is on your side (up to the point where you do any malicious or criminal damage etc obviously).

Once a contract has been drawn up with the landowner or landowners for a particular wind farm, it’s time to design a layout. This remains a challenging issue.

There are a number of criteria which are likely to restrict your options before the wind can be taken into account. These will include bird and wildlife surveys; land use and availability for roads; waterways and steep valleys which restrict access to heavy plant; planning restrictions on tip height; noise considerations; nearby residents; ground suitability; and local considerations such as archaeology, sites of scientific interest, and so on.

From there, the best practice is to use actual wind measurements to model how the wind flow changes across the site. Because you need at least a year’s worth of data from a met mast before you can really use the data (to cover all seasons), the reality of this part will vary substantially depending on how far into the project we are. If the project has two years’ of measurements at one or more masts on site, then great. Otherwise there are other sources of wind information we can use: bought data from a Met office measurement station; a virtual met mast built from a model; reanalysis data based on satellite measurements; extrapolation based on a combination of measurements. If the worst comes to the very worst the rule of thumb that “higher elevation = windier” would provide at least a guide.

Once you have an idea of the wind flow, you need to decide where to put the turbines. There are a number of things to take into consideration when doing this.

Each individual turbine removes a little of the energy from the wind it encounters, resulting in a slower wind speed for those turbines behind it. It also increases the turbulence, which further reduces the effectiveness of the turbines behind: it’s harder to extract energy from turbulent air. The combination of these is called the “wake” effects in the industry. To reduce the impact, it’s considered best practice to leave between 4 and 7 rotor diameters’ worth of gap between the turbines. Larger spacing is generally left in the predominant wind direction so that the overall wake effect is lower. (Offshore the spacing is larger, because wakes travel further offshore for reasons to do with atmospheric effects. Best practice will also vary from region to region based on the appropriate climate drivers.)

Trees and slopes will have several impacts on your positions. The top of a hill will be the windiest location, but steep slopes can provide huge challenges for accessing the turbines for construction or maintenance. Steep slopes also tilt the wind to an angle, and above 17° or so start to cause real problems for accurate wind flow or turbine performance modelling. Forestry increases turbulence directly above the forest, and can have other effects on the wind flow (increased change in wind speed with height, for instance, and boundary effects at the edge of the forest) which reduce the efficiency of the turbines.

Dwellings should generally be avoided as far as possible. I think the guideline in Scotland is 500m (note: there are experts on these constraints, and I’m not one), but a much larger buffer zone is wise. The issues of noise and shadow flicker are only relevant with regards to nearby homes. The danger of ice throw from blades or of blade throw is not thought to be a risk beyond tip height of the turbine (so if the turbine is 160m tall and you’re more than 500m away the risk to your property from these things is vanishingly small). To be honest I think the main driver here is the good will of the community. Big wind farms are generally built by bespoke developers, and there is much to be lost in appearing to trample over communities.

You want to maximise both the number of turbines and their output. Developers (or the banks who lend to them) take on the financial risk of a project when they sink their money into constructing the wind farm; they get nothing back until they start to produce electricity. If the costs of building and maintaining the wind farm turn out to be more than the wind farm can generate, the project is a failure. So the energy output is actually critical to project success.

Ultimately, then, from an industry perspective, the challenges of layouts are as follows:

  • Comply with all planning restrictions
  • Keep the local community on-side as far as possible
  • Space the turbines 5 by 3 rotor diameters, which for an 82m rotor diameter machine (about average for large wind farms at present) is 410m by 246m
  • Keep the turbines away from steep slopes, forestry, and dwellings as far as possible
  • Install as many turbines as you can to increase your maximum production
  • Put your turbines as high up as you can manage

I’ve often seen the accusation “poorly sited” levied at wind farms in newspaper letters. Reading between the lines, I suspect that this is because the writer objects to wind farms on hills where they can be seen, rather than that they know a secret way of establishing the best place to put wind farms that the industry hasn’t stumbled on yet.

On austerity

I think the people most impacted by the current government’s completely inexplicable austerity drive are the people who rely on state money, whether as benefits or because the state pays their wages. I am in the very fortunate position to be privately paid, and in a high-skill, high demand area.

Even so, I’ve found that the austerity measures are having an impact.

I guess the first thing I’ve noticed is that my money isn’t worth as much, and my time isn’t worth as much. Wage rises are very low, generally less than inflation; and the rate of interest you get on any money you can afford to save is actually laughable. (My “interest paying current account” was demoted to “current account” when it stopped paying interest, and I recently saw a poster advertising an actual ISA with 3% interest which only a few years ago would have been miserly for instant access savings.)

At the same time, the public discourse is highly demotivational and depressing. “Do more with less”. Services being cut at every turn. Tabloids turning on the unemployed, the sick, and the disabled, as though the tiny fraction of GDP which represents benefits for the genuinely needy is anything to do with the size of our defecit. On a personal level, individuals have to stretch their money to pay for their own higher education, their own retirement, childcare for any children, their day-to-day living expenses, the astronomical cost of housing… It’s depressing to feel like your time is not worth as much and at the same time to know that you have to pay for your past, present and future (and that of any dependants) out of a shrinking pool of income at a time of high inflation.

And of course by cutting benefits the government is telling me in no uncertain terms that if I fall sick or lose my job, I’m on my own. And I actually can’t save up for that possibility because I’m too busy saving for home repairs, pensions, student loans and you know, actual living expenses.

The thing is, if you’ve always had money you won’t see that. If you are in the fortunate position of having always had a little bit put by either by your parents or through some other means then you’ll never see cost as an ultimate problem. Similarly if you bought your house in the early days of the boom and sailed up the housing ladder on equity then you won’t appreciate how different it looks when you stretched yourself to the limit at the end of the boom to buy your house and watched its value fall through no fault of your own. The rich don’t see money as a problem, it’s always there when they need it. It’s more a way of keeping score.

Any household which covers its debts by letting its members starve and die is doing something wrong. That’s what this government’s austerity politics are doing, as disabled people are villified by their neighbours for the pittance we spare them. The government is letting us down; failing in its duty of care to its own citizens.

It sounds like socialism, and it is. Because how can it be bad for the resources of the many to be used to help those with nothing? You can only villify socialism if you genuinely believe we all have equal opportunity to be rich. And you can only believe that if you walk around with your eyes closed and your fingers in your ears.

(For context, I just read this. Alongside some other things I’ve read, the whole thing really worries me. I have worries about the independence debate, most notably regarding how little information seems to be available about what the former Great Britain might look like after independence, but this government would drive me to a YES vote on the grounds that at least Scotland might not have to face the worst. And if it’s impacting me, the picture of the squeezed middle, how much more must it be hitting the genuinely poor?)

Normal service will be resumed shortly…

I’m starting to get really worried about the wind industry. I think it’s an important industry, for several reasons:

  • It brings jobs to Scotland, even in a time of recession,
  • It allows for our dependence on imports for electricity supply to be reduced,
  • It reduces the carbon intensity of our energy,
  • It serves as a point of learning on the road to making real use of our renewable resources: solar, wave and tidal, and whatever new technology comes after.

What worries me is that the debate on wind energy, from the pro-wind side, is totally dominated by three voices: the economists/business leaders, the politicians and the green activists.

The way I see the world, politicians are there to tell us if something should be done; economists tell us if people will pay for it; and activists are there to lobby for a pre-existing set of ideas. When it comes to “can something be achieved”, that’s where you need the geeks: specifically the scientists and the engineers. And the scientists and engineers are very, very quiet on the issue of wind power.

Part of the reason for this is that wind energy for large-scale electricity is still very much in its infancy. Ten years ago, the procedure for installing a wind farm was completely unrecognisable compared to what happens today: masts were smaller, turbines were smaller and closer together, and the softer requirements like bird surveys and protection for peat lands weren’t as well established. Ten years in a career is a long time; but it’s hardly any time at all when you look at how quickly the onshore wind industry has grown. (Offshore wind has barely begun its journey yet, so I’m not talking about that.)

Within that huge rate of growth, large companies have grown from small groups of tinkering engineers, and somehow the managers, the politicians and the economists have become the dominant voices. And they say: protect our IP, don’t say anything which will bring the industry into disrepute, keep to the party line. It’s scientists who say, share data, do best practice and let people see it’s being done. But somehow the scientists and the engineers aren’t making the decisions in this industry. And where they’ve risen to the top, they seem to do so by falling in line with the industry position. Don’t question, don’t talk about any issues, don’t ever suggest there’s anything wrong. And so they become the business leaders, the economists, the politicians.

One result of this is that an industry which employs hundreds, perhaps thousands of highly-qualified engineers, and a fair few scientists too, doesn’t seem to have the geeks on their side.

I’m talking about this blog. The author of the blog is Colin R McInnes, a professor of engineering at the University of Strathclyde. As a citizen, he’s been writing to newspapers fairly often lately. His letters tend to be good engineering, as you’d expect, but they tend to come down on the anti-wind side.

He’s not correct. But, and this is important: IT IS NOT HIS FAULT THAT HE’S WRONG.

He’s an engineer. More than that, this guy researches into solar sails for a living. If you asked him about whether solar sails were worth investing public money in, presumably he’d say yes. This is frontier research: it can’t fund itself without huge subsidies. Yet this same man is essentially arguing that if offshore wind farms, a very new attempt at large-scale deployment of technology to an extremely challenging environment, can’t fund themselves commercially then they should be scrapped. So what’s the difference?

He doesn’t know that we’re here. The scientists and engineers who are tasked with building wind farms and actually making them work. He’s not in the industry, doesn’t go to conferences or meetings. He’s only engaging with the public discourse. Which is, as I stated earlier, dominated by politics, activists and the party line. He is operating in a complete vacuum of technically-literate information on wind farms.

We need to start talking in a language that the technical people can understand. That means demonstrating good practice and actually letting the numbers out there. How much are wind farms generating? Why are they being installed where they are? What are the measured capacity factors? How do we determine the layouts? What actions do we take to mitigate public concerns? How do we re-power or decommission a wind farm at the end of its life? Are we held to account if we breach our planning?

I don’t know if I can make this happen. This blog is a start, I suppose. Perhaps you can. The time for secrecy is ending; if anything I’m very concerned that we’re already too late. What might have been good for an individual company is threatening to doom an entire industry. And that industry matters.