Wind Turbine Efficiency: How Has It Improved Over Time?
 Topic: renewable energy |  Read Time: 6 mins |
 Landowner type: All |  Energy: Onshore wind |
9th May 2025Have you ever wondered how wind turbine efficiency has changed over the years? In this in-depth article, I’ll uncover the major changes in wind turbine construction since 1987.
Wind energy plays a vital role in the UK’s electricity mix, but have you considered how turbine efficiency has improved?
Believe it or not, between 2009 and 2020, electricity generation from wind power increased by 715 per cent.
With 2020 named the ‘greenest year on record’ by the National Grid, it’s clear that we’re making progress.
So, how have we managed to increase our generation capacity so significantly in just 10 years? And what does the future hold for wind power in the UK?
This article will cover how wind turbines work and the innovations that have made them more efficient over the years.
How Do Wind Turbines Work?
Wind turbines have a special rotor that turns when the wind hits the blades.
This movement then turns a generator that produces electricity, which is then sent to the grid.
A turbine’s effectiveness depends on its location. For example, you’re far more likely to get a decent amount of energy in a high-wind area than somewhere with virtually stagnant air!
Offshore wind turbines are typically larger and experience higher wind speeds than onshore turbines.
How Efficient Are Wind Turbines?
Before we discuss the improvements to wind turbines over the years, you might be wondering how efficient wind energy is in general.
Although no turbine will ever be 100 per cent efficient, it’s said that they’re between 20 to 50 per cent efficient, depending on the time of year.
During peak wind periods, efficiency can reach around 50 per cent, but it drops to around 20 per cent when winds are lighter.
That said, wind turbines produce electricity for around 80 per cent of the year on average, making them a reliable source of renewable energy for the UK.
Why is Wind Energy So Important?
Wind energy is gaining popularity for several reasons. It’s a clean, renewable source of energy, and the UK’s strong winds make it a perfect fit for the country.
Wind power doesn’t produce air pollution, making it a key component in reducing carbon emissions and transitioning to a fully renewable energy system.
Wind energy is also crucial for helping the UK meet its net-zero obligations by 2050. Although we’ve come a decent way in decreasing our emissions since 1990, there’s still a long road ahead.
As of 2023, the UK has 11,000 wind turbines installed onshore and offshore. This boasts an impressive installed capacity of 28 gigawatts.
Plus, the UK’s shallow continental shelf means that the seas around our coasts are ideal for offshore wind turbines.
Although constructing new turbines requires a substantial upfront investment from developers, the potential returns (both environmental and financial!) are worth the effort.
Looking at Wind Turbine Efficiency Over Time
If we look at the history of renewable energy, we can see that the first wind turbines were installed on UK land back in July 1987.
This 3.7 MW turbine was tucked away in Orkney and was the first installation to provide clean energy to British homes.
Since then, turbines have gradually grown in size and efficiency.
In 2018, a large 260-metre-tall turbine was revealed by GE Renewable Energy and was designed to provide enough energy for 16,000 European homes.
And onshore?
Well, in 2017 we were graced with a 4.8 MW turbine with a mammoth 158-metre rotor and tip heights of up to 240 metres!
What Changes Have Been Made to Wind Turbines to Improve Efficiency?
Hub height
Hub height is a huge factor that has increased wind turbine efficiency over the years.
The average height of a wind turbine has increased a whopping 66 per cent since early turbines were installed in 1998.
As of 2021, the average turbine in the US is approximately 94 metres, with UK turbines hitting around 74 meters, according to RenewableUK.
However, it’s possible that modern UK turbines could now reach US standards with Labour’s decision to loosen onshore wind planning guidelines. So, you’ll need to watch this space.
Generally, the higher a turbine tower is, the more energy it can capture since wind speeds typically increase with altitude.
They also face less resistance from obstacles on the ground, benefiting from above-average wind shear.
This is otherwise known as the change in wind speed with altitude!
Rotor diameter
Rotor diameter plays a key role in wind turbine efficiency. It refers to the width of the circle created by the turbines when the blades spin.
Over time, turbines have been built with longer blades, allowing them to capture more wind and generate more energy.
It’s believed that the average rotor diameter worldwide has increased sixfold in the last 30 years – from around 20 metres to 129 metres.
Talk about progress.
Better materials
Over the years, the materials used to construct turbines have also improved significantly.
Most modern turbines are constructed with glass and carbon fibre composite materials, which are generally lighter and more efficient than previous iterations.
Don’t worry though – they’re still incredibly strong!
Depending on the location, you might also find parts of onshore and offshore turbines constructed from aluminium and wood.
To make things even more appealing and environmentally friendly, between 84 per cent and 90 per cent of a wind turbine’s materials are recyclable.
With better materials generally comes improved functioning and a longer lifespan.
The result? Greater wind turbine efficiency!
Better predictive maintenance
Although every wind turbine requires scheduled maintenance, improvements in sensor technology have made it easier to predict major faults and prevent failures.
While previous turbines relied on condition monitoring and failures in generators and bearings, modern technology is way ahead of the game.
Modern turbines use fluid and vibration sensors to detect potential issues, such as gearbox failures, before they happen, improving reliability and efficiency.
A Final Word
In my opinion, the future of wind energy is looking more positive than ever before.
With the Conservative government moving out and Labour moving in, planning rules are already softening in favour of onshore wind.
While turbine technology has advanced significantly in recent decades, major changes may slow in the near future. However, with the UK’s net-zero deadline edging ever closer, Labour’s push for wind energy could further reduce reliance on oil and gas.
And is the UK population willing to champion renewables? Well, we’ll just have to wait and see.
FAQs
Over the years, several different clients have asked me about wind farm trends and just how reliable wind energy can be.
Here are some of the questions clients have asked (with answers, of course).
What percentage of UK electricity is generated by wind turbines?
According to the National Grid, wind energy made up 26.8 per cent of the UK’s total electricity production in 2022.
What is the trend in wind power in the UK?
As the UK has a target to increase offshore wind capacity to 50 GW by 2030, it’s a good sign that more turbines are going to pop up offshore. While there has been resistance to building onshore turbines for several years, looser planning guidelines should see this change quite quickly.
How loud is a wind turbine?
People often argue that wind turbines are eyesores and can be too noisy.
Regular background noise tends to register at around 40 to 45 decibels, and the average fridge operates at 40 decibels or so.
It’s said that sound pressure levels for wind turbines are around 38 decibels. This means that the average person won’t hear most noise from any turbines.
In very rural areas you might hear a very quiet buzz – but even then you’d strain to hear it. As wind turbines become more efficient and develop over time, they may get even quieter.
Plus, it’s worth remembering that turbines will always need to be a minimum distance from the edge of any home.
How long do wind turbines last?
An average wind turbine will last between 20 and 25 years, but it will likely need maintenance over time.
For this reason, it will take a few years (at least) to get a decent return on your initial investment.
But it’s entirely possible to extend planning permission through repowering if you want to benefit from your site for longer.
There You Have It: An Overview of Wind Turbine Efficiency
If you want to learn more about the efficiency of your site or have any questions regarding a wind farm extension, get in touch. Our expert team will be more than happy to help.
