Winding up Wind Power

Perhaps there’s been a recent birth in your family? If so, are the new parents being swayed by popularity trends? Mitchell Newberry is an evolutionary biologist at the University of Michigan, and he explained to Julia Ravey what drives the popularity of baby names…

Mitchell - As soon as a name gets about one in 500 or 100 babies, people really don't want to use it anymore. And if you look at the most popular names at any given point in time, they're probably part of these boom bust trends. And so those names get more popular than any other names really do.

Julia - So you mentioned there, there were these boom bust cycles with names. What exactly are those?

Mitchell - Some names, like for example, Britney, just didn't even exist before about the 1950s in the US. And then by 1990, it was the most popular name. And about 75% of people that were named Britney were born between 1985 and 1995. So this name went from something that really nobody had ever heard of to being the most popular name. And then the trend went out as quickly as it had come in.

Julia - And why do you think we steer away from names once they reach a certain frequency in the population?

Mitchell - Well, it's probably just what it is to be a name. We wanna be able to identify ourselves. And so being unique as part of what a name is, and I don't know about you, but my elementary school classes had two or three Jessicas per classroom. You know, so maybe that's annoying

Julia - Are the names that retain a certain frequency in the population?

Mitchell - Yeah. So not all names are boom bust. There's plenty that are perennially popular, maybe because they're just in this cultural repertoire. So we've noticed for example, names that are in the Bible tend to be given a little more often than other names.

Julia - Does it also coincide with instances in popular culture? So if a film comes out?

Mitchell - Yeah. So names do respond to popular culture. And one of my favourite examples of this is Maverick, which didn't used to even be a name. It was a last name, but there was a cattle rancher in Texas who refused to brand his cows and the cows that didn't have a brand became Mavericks because they were renegades or, you know, this Maverick character, he wasn't mainstream. So it started to refer to a personality type. And then Tom Cruise in Top Gun got Maverick as a nickname. And then gradually over the last 30 years or so Maverick gradually became a name that people would actually name their babies. And today it's the 50th most popular name in the US.

Julia - Oh my goodness. Are we seeing, as we become more individualistic as a society with, you know, the rise of social media, all of us are being sort of driven to be these individualized selves. Have we seen changes in the frequency or uniqueness of names like this Maverick example, a name just sort of coming out of nowhere?

Mitchell - Yeah. Well, we're able to kind of measure at what frequency in the population a name really starts to be rejected because it's too common and that frequency has somewhat declined over the last hundred years in the United States, but we've actually also been able to show that people's sensitivity to how common a name can be before they start to reject. It has also changed. So people are more sensitive to how common a name is than they were in the past.

Julia - Right now in the UK, the most popular girl's name is Olivia and the most popular boy's name is Oliver. So how long do you think they'll sit on the top spot?

Mitchell - That's so interesting because a friend of mine asked me to consult with them about naming her baby. And she gave me a candidate list of names and they actually included Olivia. And I looked up the whole list of names in the database and found that my friend is actually quite on trend. All of the names that she gave me are trending upwards right now in popularity, but they all had a curious similarity that they had also had big trends about a 100 to 120 years ago. And so some of these trends that are currently happening, like I said, if any name that's the top name at any given time is likely to be a trend. And so it's likely to fall out of fashion, roughly the same way that it fell in, but these names that are popular now and Hazel and Emma are some other examples were also popular a hundred years ago. And so these trends kind of cycle on these long intergenerational timescales.

Hailed as one of the solutions to the current energy crisis, Small Modular Reactors - or SMRs - are intended to fill the renewables “gap” when supplies from alternative sources cannot be relied upon: like the loss of solar power at night, for instance. The intention is that they should step into the breach to replace the UK’s ageing and retiring nuclear fleet as the last few existing nuclear stations go offline. So, has new research suggesting that SMRs will produce 30 times more nuclear waste than existing larger station designs effectively put the concept on hold? Chris Smith spoke with Sheffield University’s Claire Corkhill, who works on how we handle nuclear waste, to hear her take on the matter…

Claire - The paper that was published this week by Lindsay Krall and her colleagues at Stanford took a look at how much radioactive waste is gonna be generated from small modular reactors compared with the larger types of pressurised water reactor that are being built around the world, including in the UK at Hinkley Point C. And what they did was an assessment of exactly what kinds of wastes are gonna be generated in terms of the nuclear fuel, but also reactor components. And what they found was that a small modular reactor will generate about 30 times more radioactive waste than a pressurized water reactor, depending on the reactor design.

Chris - And when you say a pressurized water reactor, we're talking about the sorts of things. We are currently deploying more mainstream, large nuclear reactor that we currently use to generate electricity.

Claire - Yeah, that's right. So we currently have one of these at Sizewell B and we're building another at Hinkley Point C, they generate about three gigawatts of electricity. So that's like boiling a hundred thousand kettles all at once^*. Whereas the small modular reactors, which are really relatively new on the scene, these are much, much smaller and they're a hundred megawatts of electricity. So that's more like boiling three hundred kettles at once.

Chris - But the government have very much got behind this concept. Haven't they? The regulator received an approach from Rolls Royce to table some ideas or some plans for how to do this. A number of other companies have now entered the market with designs to do this. People think that they're an excellent idea. Why is there this disparity?

Claire - Well, one of the major reasons, and for the popularity of SMRs is really their size. They're much smaller than these very large PWR reactors, which are extremely expensive to build. We've seen the cost of that Hinkley Point C reactor just increase and increase by millions and tens of millions of pounds, year on year throughout the construction process. So by building smaller reactors, the advantages that we can manufacture all of the components within the UK, we can use the supply chain that's already established here to build more economic reactors.

Chris - Well, if there are economies of scale that you can get with the SMRs, why does that not also transfer to the waste?

Claire - That's really interesting question. That's precisely what Lindsay Crawl and her co authors have discovered in this paper. One of the major issues is actually to do with the size. So if we think about how a nuclear reactor works, we have uranium atoms that are splitting and they create neutrons subatomic particles. And these neutrons, we use them to power the chain reaction. They go on to split more atoms of uranium. Now to make that as efficient as possible, we need to keep the neutrons inside the reactor. But the problem with small modular reactors is it's difficult to do and what we get is something called neutron leakage. What that means is that these neutrons then start to interact with the structural components inside the nuclear reactor, and it turns them radioactive. So the stainless steel, for example, that the reactor's built out of then becomes radioactive. And that is then when it comes to decommissioning those reactors intermediate level waste that we have to manage and dispose of.

Chris - Where does the difference between relative and absolute come into this? Because relatively, yes, it's producing about 30 times more waste than a massive great power station. But given that these are much smaller, does it still not translate into a very small amount of waste? And given the other benefits that would come with embracing this technology, it still adds up to a good thing, or is the case overnight becoming a lot less compelling thanks to this research?

Claire - We really do need a short term fix to the energy crisis. And there's good potential for small modular reactors to come to the rescue here. That being said, you know, in comparison to other technologies like wind and solar and so on, they don't create the same kinds of wastes as we've been discussing here. So I think it's a balance. We need to think about what we need in terms of generating our electricity now and what we are happy with being the consequences moving forward in the future.

[*We think Claire meant a million or so kettles here, rather than 100,000: assuming a very energy-hungry kettle draws 15A at 240 volts, 100,000 such kettles would use only 15*240*100,000 = 375,000,000, or 0.375GW, rather than 3GW.]

Now, scientists believe that they can ascertain prehistoric food chains by looking more closely at the chemical composition of their teeth. Jeremy McCormack from the Max Planck Institute for Evolutionary Anthropology, believes his recent study of the giant Megalodon’s giant gnashers could lead us to the cause of its demise. Harry Lewis reports...

Jeremy - They went extinct around 3.6 million years ago, and they had a worldwide distribution. It is the last member of the so-called mega tooth lineage. And the megalodon itself could have potentially reached sizes of up to 20 meters in total length.

Harry - You were able to compare the diets of different shark species, including that of the great white shark and the megalodon, because they were at one point in time, both swimming around together, and you've used zinc isotopes to do that. How can those isotopes help?

Jeremy - An isotope of course the same element, but with a different mass. So we look at the ratio of the heavier zinc to the lighter zinc in the mineral of these teeth, and this ratio tells us how far up a food chain an animal was feeding. The way this works is that the zinc isotope ratio changes as we move along the food chain within the vertebrae remains of different animals.

Harry - Right. And why is it that teeth make for such good samples?

Jeremy - So we look at teeth because teeth are very well preserved as fossils over millions of years. And because zinc is incorporated into this mineral phase of teeth, we basically can look back millions of years, study the diet along extinct animals.

Harry - Were there any similarities then between the diets of great whites and Megalodons?

Jeremy - There is this hypothesis that the emergence of the great white shark during the early Pliocene led to competition for dietary resources between megalodons and great white sharks and our zinc isotope results show that both species fed on a similar trophic level. And now this does not necessarily imply competition, but it really doesn't reject the hypothesis of competition between both species.

Harry - I've got you. So they could have been eating pretty similar prey. Can we guess at where the diets of these two sharks may have crossed over?

Jeremy - So from fossil evidence, we know that both species, at least occasionally fed on marine mammals. So these included both toothed and baleen whales, although the baleen whales back then were much smaller than they are today. Um, but such kind of fossil evidence is rare, and it only gives us a snapshot of predator-pray interaction and does not give us the information about the regular diet of these species.

Harry - And of course, what makes it so fascinating is it's the first time that this method using zinc isotopes to infer one's position in the food chain has been used on such old samples. So there must be quite a lot more to come. This is an exciting time?

Jeremy - Yeah, that is ultimately the goal to use this new method, to investigate the diet ecology of longing animals, which obviously has important implications for their evolution. But in some cases also their extinction.

We've been using wind to generate electricity for over a century, but for thousands of years, and of course long before electricity became our energy currency, wind power was still a staple. Back then, our forebears used it to move water and to grind grain. Julia took a trip to Burwell museum and windmill in Cambridgeshire to hear how...

Andrew - Welcome. My name is Andrew. I am the head of the mill team at Burwell Museum, and we are in charge of maintaining, preserving and operating Steven's Windmill Burwell, which is the last working corn mill in the village. She's 200 years old and I have been working with her for the last eight years.

Julia - Wow. Well, she looks good for 200 years old. How high is the windmill?

Andrew - The main tower is approximately 50 feet and each sail is about 35 feet long. We get nearly a hundred feet by the time you get to the tip of the topmost sail.

Julia - Wow. It's big.

Andrew - Yes. This land has been called Millfield since the 1200s. We have found evidence of windmills dating back to the 1300s.

Julia - So, we've been using wind power all that time.

Andrew - Yes. There has been wind power used in this village for at least 700 years.

Julia - Let's go inside. I'd love to see how that mechanism works.

Andrew - We call this the great spur wheel. It's the largest diameter wheel in the whole building. It is the penultimate gear before the stones. It turns free stone nuts, which then turn the free pairs of stones above. This mill, when it was built, was capable of grinding three different meal; flour, rye, barley, and also had a grain cleaner and a sieving machine to produce white flour.

Julia - All of those different contraptions, are they powered by the wind?

Andrew - All can be powered by the wind, yes. All powered by gears coming down from different gearing and different take-off drives.

Julia - Am I allowed up here? Oh my goodness. This is a steep staircase.

Andrew - This is the most important floor in the mill. This is what we call the stone floor. It is also here that you can see our principle secondary drive, what we call the crown wheel, which was the wind powered drive that drives the auxiliary machinery, including the grain cleaners and the white flower machine, which we call the dresser.

Andrew - (Tapping noise) So, you can hear that noise. That's the shoe, which is rattled by a large lump of metal projecting out of the stone called a mace. That rattling gently feeds grain into the eye of the stone and is then drawn through by the motion of the stones which, in a scissoring action, cuts the grain open and releases the flour. Then it comes through to the shoot which takes it down to the ground floor. In the Victorian period, we had four corn mills in the village alongside countless small drainage mills which assisted in draining the fens. There were many examples of wind power being used for different purposes. We were a corn grinding mill. They also had pumping mills and they also had mills that ground fertiliser for the local farms.

Julia - We're really making the use of the windy area that we live in.

Andrew - Almost certainly. We still use wind power to operate and we are very pleased that we can do that.

Julia - Not knowing when the wind will blow and how hard is one of the main drawbacks confronting energy companies that rely on wind power to supply their customers. If they bank on seeing a certain level of supply, but a law means they're short of power, they have to make up for the shortfall by buying supplies off their competitors, often at shockingly high prices, undermining the viability of their business. But if we improve our short term weather forecasting for turbines so predictions about wind speeds and therefore outputs can be improved, the situation is much less risky for the operators who are more likely to invest. That is what Martin Shields from Colorado State University is trying to do as he explained to Chris.

Martin - Our problem is, how do we provide a better wind forecast to utilities so they can better plan for producing tomorrow's electricity demand.

Chris - That sounds like a bit of a trivial problem, though - it might not be windy tomorrow, we'll just get the electricity from somewhere else? Is that not how it works?

Martin - Well, sure, you can go out on the market and buy it from someone else, but it's a lot more expensive when you expected the wind to blow and it didn't. You have to go out and pay a lot of money for electricity on what's called the spot market.

Chris - Are our forecasting methods good enough to give that kind of fine grain detail, though? What sort of resolution of energy generation, and also wind speeds, are we talking about?

Martin - Well, we are looking at winds that are very localised. We need to know how the wind is going to blow near the wind turbines where the electricity is produced. That's a tough act for forecasters to do. It's really difficult to know how fast the wind is going to blow at any particular time in a very small locale.

Chris - So how are you going to solve that for them?

Martin - We work with scientists at the National Oceanic and Atmospheric Administration, part of the US government, and every day they're hard at work, fine tuning their models. What we do, in our project, is look at how the old model that's currently running does in predicting wind 12 hours ahead versus the developmental model, which is behind the curtains. 12 hours later, we see how good those predictions are. We look at what the cost of a mistake is under each of those regimes. What we found is that, as the model is improved by the scientists, there are substantial savings and that can subsequently be passed on to consumers through lower electricity rates.

Chris - Does this give generators more confidence, essentially, to invest in this and go down this path because rather than take the sure fire way of generating electricity, you burn some coal, or some gas, or some oil, you know how much that's going to cost you, you know that you're going to get electricity at the end of it, and therefore very low risk. Versus, if you've got to take a gamble on the weather, high risk. Whereas if what you are doing can be brought to bear and prove that actually they can save a few bob, it does mean they're more likely to invest in this sort of market.

Martin - Exactly. The uncertainty of wind is an impediment to its adoption. Sometimes it blows and sometimes it doesn't. But, also, the uncertainty about the uncertainty is an impediment. What we're trying to do is remove the uncertainty about the uncertainty, and that provides value to the utility and helps increase the likelihood that they'll use more of it.

Chris - Where are you basing the analysis because is this going to be applicable everywhere? And what about with an eye on the future? People are very worried about climate change and some of the predictions about the rate at which that is going to happen are quite scary because they suggest quite near term changes and they're very variable. There's a lot of those uncertainties that you're referring to geographically as well. Are we looking at an even more uncertain future and therefore how much certainty can you bring to the uncertainty at the moment?

Martin - That's a tough question, Chris. We're doing this for the continental United States and, even within the US, our wind forecasters do better jobs in some places than others. As we introduce climate change - we know it's happening, what we're trying to do is make this transition to whatever the future holds as costless as possible, or as least costly as possible.

Chris - Are utility companies receptive to this kind of thing? Can you see them actually having trust and confidence in the sorts of numbers that you are beginning to generate?

Martin - Yeah. We've talked to a few utilities who are clamouring for this information. It really is an expensive problem when there's a mistake made and anything they can do to keep rates down to consumers, they're excited about. We're just hoping that we can help in that effort. It might be a few dollars per year or a few pounds per year for the average customer but, when you add that up across the economy, it can run into the hundreds of millions of dollars in annual savings and that's money that can be spent on other things. People can have something a little bit more exciting in their lives than electricity.

Although wind turbines are providing huge benefits in terms of us getting more clean energy into the UK and around the world, on windy days at least, it's important to recognise that these are really huge, potentially intrusive structures. These turbines jut up hundreds of feet into the air. So what impact is that having on birds which normally fly through these paths? And for offshore wind farms, are they impacting life below the sea? Over to Chris Smith...

Chris - There are thought to be over 8,000 onshore and 2000 offshore turbines in the UK alone now, with numbers still rising. While the energy they generate will over time, of course, form part of our solution to the climate change problem, their immediate impacts on proposed construction sites do of course have to be taken into account...

Aedán - So we're not only in a climate emergency, we're in a nature emergency as well and wind turbines, wind farms -really good at generating low carbon energy, so that's really positive, but they do present some risks to birds and their habitats

Chris - That's Aedán Smith, he's head of policy and advocacy at RSPB Scotland. This danger was highlighted in one of the first wind farms in the United States in Altamont Pass, California...

Aedán - It's really important migratory route for lots of bird species, and lots and lots of birds were tragically killed by colliding with the turbines there as we were passing through

Chris - From this tragic incident, bird behaviours and habitats are now taken into account before a turbine is erected...

Aedán - Working with conservationists and with government agencies to avoid the most sensitive places for the most part. So that fortunately has meant we've not had too many of those really terrible situations like at Altamont pass.

Chris - Even though some may argue that more birds are killed by cars and cats in a year than turbines, particular species might be more vulnerable...

Aedán - There are not all that many Eagles for instance killed by domestic cats, but actually that is a sort of species that is potentially at risk from colliding with wind turbines

Chris - Wind turbines can disrupt bird populations in three ways with the first being...

Aedán - Collision. So collision with a moving turbine blades. The other thing is though that these structures are novel if you like, it's not something which wildlife has evolved to coexist with. So sometimes birds see a turbine and then go absolutely nowhere near it, which is great for avoiding colliding with this structure. But maybe if they avoid an important feeding area or nesting habitat, then that could have an impact on their ability to survive. And a third type of impact is more of a barrier effect. Birds often will nest or roost in a certain location and then go off to feed somewhere else; they're journeying, they're commuting, if you like. And if a wind turbine suddenly appears on that commuting route, they may need to avoid that. And if the bird is using up every last ounce of energy just to survive, and then suddenly it's got to take a longer route, that could maybe tip the balance and tip it over the edge

Chris - These factors are taken into account when sighting turbines to avoid disruption to populations, and we've now got years of data to help us to ensure that the sites on land are selected successfully. But when we look offshore, we don't have a similar body of data to fall back on yet. So it's much trickier to predict what sort of impacts these turbines are going to have on that wildlife. There's currently also a conflict between generating more green energy by erecting more offshore wind turbines, and trying to better understand - and ultimately protect - seabird populations...

Aedán - Fortunately, technology is helping us quite rapidly here. It's possible to put tags on seabirds and that's quite a recent development because the technology has got such that the tags have got small enough that they can fit on some of the smaller seabirds now. And that is really rapidly increasing our knowledge about where birds are going after they're leaving nest sites on the coast, and they're going out to feed out at sea, and also where they're going in the winter.

Chris - But the effects of these offshore wind turbines are not confined just to the air they spin through because scientists are increasingly documenting impacts in the underwater realm too, particularly for crustaceans like crabs and lobsters. Thanks to advances in tracking technology, we can now much better understand how these animals get about. Alastair Lyndon is a marine biologist at Heriot-Watt University, where he's been following the travails of the edible brown crab...

Alastair - Recent tagging work has suggested that they move over quite large distances, particularly the males. And it seems that they, generally speaking, move up the coast from the southeast to the north, and then from the north round the top of Scotland and down the west coast.

Chris - The female crabs, although not traveling as far, still move away from the coastline in order to brood their eggs and ensuring their numbers is vital...

Alastair - Crabs, in terms of volume and value, are the second most important crustacean catch in the UK, as far as fisheries are concerned. They're extremely important for small rural and isolated communities.

Chris - Increased numbers of offshore wind farms means inevitable changes to the surrounding marine environment, which could influence wildlife behaviour...

Alastair - It means that there'll be a lot more electrical cables around on the seabed compared to what there have been in the past. And the implication of that is that they generate a magnetic field around the cable, which can't be shielded. We know that a lot of marine organisms have - or at least we suspect have - magnetic senses, probably for navigation, using the earth magnetic field, which of course is very, very weak. So if they can detect the earth magnetic field that might interfere with any movements or migrations where they might be using that magnetic field for direction finding

Chris - It is currently pretty hard to test this theory out in the water. So Alastair and his team have set up scenarios that mimic this potential electromagnetic field effect in their lab. They did it using a water filled tank with a large coil of copper, called a Helmholtz coil, placed underneath it. And by putting crustaceans in the tank, Alastair and his team have made some striking observations...

Alastair - With edible crabs, brown crabs, when we have electromagnets under their tank and we switch them on, the crabs tend to triangulate on the magnets and then sit there without moving very much. It tends to reduce their activity levels quite substantially when the magnets are on. So it looks as though the magnetic field might actually reduce their natural movements, which might reduce their interactions with other members of the same species, so potentially mate finding, and it might also reduce their ability to forage, to feed and find food

Chris - In terms of developing offspring, the magnetic field also appears to impact another species too...

Alastair - We found that when female lobsters with eggs were exposed to the magnetic fields throughout the eggs developmental phase, the larvae were almost three times as likely to be disrupted in the development in terms of physical deformation and morphological changes. That had an impact on their ability to swim and swimming for these larval stages once they've hatched is very important because they need to be able to swim up to the surface to obtain food.

Chris - Now it's unclear if the cables currently sitting on the seabed have these impacts on crustaceans in the wild, but burying the cable was under the sand, as most companies do, might...

Alastair - Burying the cables would clearly be beneficial because the magnetic field round the cable drops off relatively rapidly with distance.

Chris - But continuing to study these effects, both in the lab and on the shore is important if we continue to move to more offshore wind energy in the future...

Alastair - It's important to know that we're not having unintended negative consequences in trying to do something good. Are the magnetic fields sufficient to disrupt the migrations of male crabs, which might have implications for the population biology of these species? How small a small effect is actually not significant as far as survival of these organisms is concerned, either as larvae or as adults? We don't really know that and we would need to do further tagging experiments to see what sort of movements might be affected by the cables in practice. We might also need to think about the impact of construction of these facilities, which clearly are on quite a large scale as well. The current practice would appear to be adequate, but we still have to continue research to make sure that there aren't any other unintended consequences.