Offshore Wind Series: Challenges, Opportunities, and the Future of Renewable Energy

In this episode of Intertek’s Sustainability Talks, host David Muil is joined by Richard Sargeant from Intertek Industry Services, to dive into the exciting and complex world of offshore wind energy. From the scale of turbines to the unique challenges developers face—like corrosion, lightning strikes, and environmental concerns—Richard breaks down what makes offshore wind so different from onshore. The discussion also explores the financial viability of offshore wind, the latest technological advancements, and the future outlook of the industry. 

Tune in to learn why offshore wind is considered a key player in the global transition to green energy, and what makes this sector both challenging and thrilling. 

To connect with our expert Richard Sargeant, email richard.sargeant@intertek.com.

For more information and the latest updates, please visit us at http://www.intertek.com/wind and feel free to come see us at our Offshore Wind Events that can be found at www.intertek.com/events/2025

Speakers:

• David Muil - Global VP of Sustainability for Intertek
• Richard Sargent - Offshore Wind Strategic Development Lead at Intertek Industry Services

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Transcript

Podcast Transcript

David Muil
Welcome to Intertek’s ongoing sustainability talks. The podcast that cuts to the chase to bring you everything you need to know about sustainability.
I'm your host, David Muil. Today, we're diving deep into the sea—literally—to talk about offshore wind and renewable energy.
We're going to discuss things like: Why is it so different from onshore wind?
What makes it so challenging? And most importantly, is it really financially viable?
To answer these questions today, I'm joined by Richard Sargeant, Offshore Wind Strategic Development Lead at Intertek.

Richard Sargeant
Well, thanks, David.
I'm excited to be here and even more excited to talk about what I think is one of the most exciting parts of the green energy world.

David Muil
Fabulous. Thanks for joining me, Richard. I look forward to this discussion, and without further ado, let's just jump right in and learn more about this topic. Let's start with the basics. Why is offshore wind so different from onshore wind?

Richard Sargeant
Yeah, it's a basic question, but it's also a good question too.
It's very easy to assume when you drive down the highway or if you look at some of the larger logistics companies or department stores, they'll have a little wind turbine on the top, or you may see them out on farms in the Midwest, that offshore is the same. And it isn’t.
There are really three key differences, technically speaking.

So the first one is scale.
 If you imagine the biggest wind turbine you've ever seen onshore, the largest one offshore could easily be 2–3 or even four times the size of that.
 So the scale is much bigger. If you imagine looking at a blade, a blade in an offshore wind turbine now can be as much as 130 meters, so approximately 400 feet long. That's just one blade.
 So they're much, much bigger, and obviously, there are engineering challenges that come with that.

One of the other major differences is site accessibility.
 Wind farms get built offshore to mitigate the risk of complaints from visual impairment and people not wanting them to obscure their view, so they get put far out at sea. But of course, the downside of that is when something's out at sea, it’s very difficult to reach. I'm kind of stating the obvious here, but there are so many wind farms that are way out to sea that you never even see them. You can imagine how long it takes to get there by boat.

But then the final challenge is nature's variability, and that is linked to the previous point. With onshore wind, if you have a turbine failure for whatever reason (we can maybe talk about that later), you can generally fix that with a crane, concrete, and some welding. It can be a bit of a primitive fix, but it can be done quite quickly.

With nature's variability offshore, it’s very expensive to even reach the site, let alone repair things. So the variability of Mother Nature means not only the wind and things you can see—like blades turning or not—but also the sea state, the current, and the way the seabed behaves. The seabed is an incredibly difficult thing to predict.

If you imagine you’ve got foundations piled into a soft seabed, and that soft seabed moves… anyone familiar with longshore drifts or fishing will tell you that sandbanks come and go. So, the variability of nature is the third major difference between onshore and offshore wind. And honestly, it’s why I find it so interesting.

David Muil
Oh, that’s fascinating.
I had no idea that they could be 2–3 times the size of onshore. That really puts it in perspective. That leads nicely into the next point. What are the major challenges that developers and operators are facing in this space?

Richard Sargeant
There are quite a few.
I’m going to talk about the more technical issues that developers and operators face. The obvious one is financial, and that’s quite an interesting topic in itself, but I’m going to talk about the specifics of the technical challenges because obviously, Intertek, my employer, is an inspection company, after all. So those are my primary concerns, and I’m going to give you 3 examples.

#1. Corrosion is a constant threat, particularly to the foundations and the support structure. Salt water is a fairly unforgiving medium. If you take into account the variability of the seabed, you’ve got areas of foundations being exposed that may not have been exposed. Designs have changed over the years, where previously they might have been coated to help inhibit corrosion, and now the designers allow free corrosion. So, they simply don’t fight Mother Nature—they just let Mother Nature do her thing.

So, there are a lot of variables in corrosion, and again, we’re really at the early phase of offshore wind globally speaking. Even though it’s a huge industry, there’s so much more of this coming as all these assets get built and get older. They’re all going to corrode.

This is a really interesting topic, and there are certain things that can be done around it. I can give you a couple more. Lightning strikes on turbine blades happen more frequently than you think. And of course, it’s exceptionally costly if it causes a fire or other damage.

Now, the latest turbines have a very sophisticated lightning protection system, which essentially is a conductor that attracts the lightning strike, much like it would on a church steeple or a tall building. If you imagine out at sea, a wind turbine is hundreds of feet tall—it’s the tallest thing in the air, so it’s going to attract lightning. On the other hand, lightning protection systems are not immune to failure.

Also, now as they’re starting to use composite materials in the blades (instead of glass fibre, they might be using carbon fibre), the way lightning behaves when it hits the turbine is relatively unknown and exceptionally complex to understand. So, lightning strikes happen all the time, and they can be quite costly if you damage a blade. We go back to that being offshore—how easy is it to actually remove a blade and repair it when it’s nearly 400 feet long? And then, of course, there’s the cost of downtime associated with that as well.

So yeah, lightning is Mother Nature doing her violent thing in a very interesting way.

Let me give you one more. You've also got environmental concerns.
 Now, this works in a number of ways. The biggest issue, frankly speaking, is the planning phase and the ability to get a permit to build a wind farm in the first place. If we go back to what we said earlier, wind farms are built offshore to reduce the environmental impact concerns, broadly speaking, out at sea. But you still have to take into account migratory birds, for example, and fisheries.

There are some fascinating studies done where operators have been hit with quite hefty fines because they’ve miscalculated and misunderstood the role of birds and how they react to the blades, which are spinning at huge speeds, or the tips traveling at huge speeds.

Also, the wider aviation—by which I mean bats and insects. In the US, for example, the few wind farms that have been built are generally quite far out at sea, and those turbines act like magnets for insects, which is very strange. There’s nothing else much going on, and they tend to wander offshore to live on offshore turbines, which then attracts bats.

Which, of course, want to eat them, and then you’ve got raptors—birds—which then, in turn, want to eat the insects and the bats. So it becomes a hub for those things. In addition, of course, you've got potential disruption with traditional industries such as fishing. Fishing is disrupted because the turbines act as foundations that subsea, serving as havens for fish and lobster. If you’ve got people trawling or fishing, they don’t want to get their nets snarled up in these things.

There are very complex and very well-regulated systems in place to ensure that disruption to avi fauna and fishing is absolutely minimal.

So yeah, corrosion, lightning, disruption to birds and fisheries—there’s quite a few interesting challenges that developers face before the wind farm is built and certainly once they’re open.

David Muil
That’s great information.
So just picking up on that, would you say that these challenges are universal, or do they vary from site to site?

Richard Sargeant
They do vary.
It’s exceptionally interesting. I would say, to start with, even with the basics of what is on the bottom of the sea. You might have a nice, easy, soft sand bed that’s easy to pile a foundation into. Or as we’ve found off the coast of the Northeast US, there’s a material called Glaconite, which should behave like sand and be easy to pile into, but actually acts like clay once it starts to impact. So, it can be very difficult to pile into.

There’s obviously a very complex geotechnical site assessment done prior to that, but really you don’t know what you’re dealing with until you start smashing things into the seabed. You’ve also got regulations around the world. You might have warm or salty waters, and, of course, ice loading on blades is a major issue for those in places like Northern Europe.

So, they do vary from site to site.
 It’s amazing how little salt is in seas like the Baltic, where they’re building wind farms. The salinity is different, and therefore, the coating and the steel might need to be different.

You can also get into wildlife interactions, and again, this is completely site-specific—migratory bird paths, where whales might appear, local fisheries—all these have to be studied and accounted for.

That’s one of the reasons offshore wind developments require pretty intense permitting and environmental regulations. But it also means it’s a very important industry overall.

One thing I want to talk about is the alternatives to doing this, because while it’s disruptive, once these things are built, they’re generating clean energy for life with the bare minimum of intervention and the bare minimum of environmental impact. So while it might seem like there are a lot of interactions with nature, they’re actually very, very minimal over the lifespan of an asset generating green electricity.

David Muil
Oh, that’s brilliant.
What is the typical lifespan of a unit that’s placed offshore?

Richard Sargeant
That’s a nice question as well.
They’re typically designed to last 25 years.
So, if we rewind to some of the earliest offshore wind farms that were built and are now operational, you get to the late 90s phase.

It’s interesting to look at those, which are now coming out of service, and to see where they failed and what went wrong. We, as a company, have done a lot of research in that area. I find it really interesting.

So yeah, the history of these wind turbines is particularly interesting, but as we now get into bigger contracts, particularly in the North Sea, the Atlantic, and elsewhere, we’re still relatively early in the industry’s life.

They’re designed to last 25 years, but we’re looking at assets now that are 15, 18, or 20 years old and thinking, “Well, what’s likely to fail with them, and what can we do better to make them last longer?” Because even the designs have improved, and our knowledge of how they perform has increased massively with operational data over the last 1 to 2 decades.

David Muil
Very good.
So, given all these challenges, you have to ask the question: Is offshore wind still financially viable?

Richard Sargeant
This is a hot topic in the media, particularly in places like the US, where changing governments and energy policies have a huge impact.

It has to be done on a case-by-case basis, of course. And one thing I also want to say is that offshore wind is only part of the energy mix. It’s never going to provide everything.

If we look in the UK, for example, very often we get the majority of our energy from wind, and the UK was one of the leading areas for green energy production from wind. In many places in northern Europe now, we’re getting huge amounts of energy from wind.

So, it is financially viable there, but of course, constructing it is the crucial difference between this and carbon-based energy production. Once this asset is up and running, it is clean, and it costs Mother Nature nothing really.

But there’s probably quite a substantial financial outlay at the outset. One of the mechanisms we’ve had in Europe and the UK is a thing called a contract for difference, which provides price certainty for developers and reduces risks, attracting investment.

Although these make the news when there are no bids for new sites, there are still hundreds proceeding around the world. So for those that might not know, a contract for difference means that if an investor invests in a wind farm and they don’t make enough money from the energy they sell from it, the government, broadly speaking, tops them up.

Conversely, if they make more money than the price they agreed with the government, they pay that back. It’s like an insurance premium that gives investors assurance they will make a minimum amount per kWh for the energy produced.

This is a great example of governments working together to ensure the long-term benefits for everybody.

There’s been a huge case in Europe recently about a wind farm called Hornsea 4 being cancelled, but Hornsea 3 is being built, and the total spend on that is about £8 billion.

These are just individual wind farms among hundreds going on around the world, so it’s huge, huge money—and it’s good for the planet.

David Muil
So, is it safe to say we’re going to see a lot more offshore farms spinning on the horizon in the future?

Richard Sargeant
Yeah, I hope they’re spinning over the horizon where people can’t see them and can’t complain about them!

That’s the best location. From an engineering viewpoint, they’re quite graceful—a bit of a light-hearted answer!

I mean, absolutely. The outlook is positive.
 There’s a global pipeline of over 250 offshore wind projects in various stages around the world, from initial planning consent through to construction. And something like 200 are already in operation, across Europe, Asia, and now the Americas.

China has changed its energy policy, and suddenly, there are dozens of wind farms in China. They’ve understood the importance of green energy and found a way to make it financially viable.

So yeah, there’s a colossal pipeline, and we’re really only at the start of what is a huge industry.

David Muil
Terrific.
Well, I hope our listeners enjoyed today’s talk. I certainly did. That’s a wrap for today’s episode of Sustainability Talks. For more information and the latest updates, please visit us at http://www.intertek.com/wind and feel free to come see us at our Offshore Wind Events that can be found at www.intertek.com/events/2025.

A special thanks to you, Richard, for joining us on this enlightening topic. I'm sure we’ll have more discussions about this moving forward.

Thanks very much.

Richard Sargeant
It’s been a pleasure.
Thank you for having me.
Bye, bye!