Wind 101

Narrator one: Ever wondered where the wind comes from? 

According to traditional Māori narratives, many moons ago, Ranginui (sky father) and Papatūānuku (earth mother) lay together in a loving embrace, holding their many children between them. The children grew tired of living in darkness and pushed their parents apart to let in the light. Their second son, Tāwhirimātea, enjoyed the closeness of his parents. Angered by their separation, he fought against his siblings, joining his father in the sky, to unleash the wind, rain and thunder into the world.  

Narrator two: Although these narratives a widely spoken and shared there are variations of perspective from Iwi and hapū across Aotearoa New Zealand.  

Technically speaking, wind is caused by the uneven heating of the earth’s surface by the sun. Heated air rises and expands, and that warming and expanding air causes areas of low pressure.  The air moves from high pressure to low pressure and it’s this flow and movement of the air that we know as wind.  

The power of the wind has been harnessed for thousands of years and in Aotearoa, we plan on doing so for many more to come. That’s because wind is a renewable resource – as long as it keeps blowing, we can use its energy to generate power. 

Our isolated location in the Southern Hemisphere, surrounded by vast oceans and unhindered by large land masses means that our winds are nice and strong. In fact, New Zealand has one of the most consistent wind resources in the world. Our wind farms operate at full capacity approximately 45% of the time, compared to the 30% of those overseas.  

Narrator one: So, if our islands have such perfect conditions for wind energy generation, why don’t we see wind turbines everywhere? 

Narrator two: Simply put, some spots are better than others.  

The best places for a wind farm are where the wind blows consistently. In New Zealand, these tend to be  on exposed hillsides and ridgelines.  

These high locations may be ideal for wind, but when it comes to construction, it can be very challenging. Depending on the size of the wind farm and its location, it can take around 2-3 years to build.  

We have to prepare by building roads up to and around the site and excavate the foundation and platform areas for each turbine location.  

Rob Batters: We’re currently in the civil construction phase of Meridian’s latest wind farm here in the Hawke’s Bay. Behind us you can see the substation being constructed which connects the wind farm to the national grid. 

Narrator two: We’ve named this wind farm ‘Harapaki’ which means ‘escarpment’, reflecting the dramatic limes escarpments of the Maungaharuru range.  

Narrator one: A substation is where transformers are used to increase the voltage of electricity from the wind turbines so it can be transported around the country more efficiently.  

Narrator one: While all this construction is happening, the turbine components are making their way to Aotearoa on ships from factories overseas. Getting the parts to site sometimes needs some creative thinking. At our West Wind Farm, near Wellington, the site was so difficult to access for trucks carrying large turbine components, we had to build our own special port to get the turbine components up to site. 

Installing the turbines is next. Because they are so big, we need special cranes to build them.  
 
Narrator two: Why don’t we build a turbine together? 

When we look at a wind turbine, we see the tower, the blades and its body – this is called a nacelle. The tower can be as tall as a 20-story building, and the blades as long as a football field!  

On top of the nacelle sit an anemometer and a wind vane. Their job is to judge the direction of the wind. That’s because, in order to get the most out of the wind, the blades need to face into it. As the wind blows, the moving air flows over the blades which creates lift and causes the blades to move.  

The moving blades are attached to the hub and main shaft. They both rotate at the same speed as the blades. But to produce electricity, we need much more speed – that’s where the gearbox comes in. The gearbox increases the rotational speed and turns the high-speed shaft and drives the generator converting the kinetic energy, into electrical energy. This isn’t the case for all turbines – some, like the ones at Harapaki, are ‘direct drive’ which means they can convert the slow rotation directly into electricity without needing a gearbox.   

Narrator one:  And there you have it! As soon as the turbines start turning, electricity is generated almost immediately, sending renewable energy into the national grid, where it is mixed with non-renewable energy before making its way down the powerlines to your house to power your mobile phone, electric kettle, laptop, waffle maker, electric blanket…..  

Narrator two: When it comes to building a wind farm, we couldn’t do it without the help of local communities and iwi. These are the people who live, work and play with the turbines in their backyards, and they help us understand their needs, the needs of the whenua and how we can treat it with respect. 

We help answer their questions and set the facts straight about wind energy and turbines. Questions like… 

Narrator one: Can you hear the turbines?  

Narrator two: The answer is yes!  When the turbines are turning, the blades make a swooshing sound,  – much like the wind in the trees!  

Narrator one: Will the turbines change the way the scenery looks? 

Narrator two: Yes, they will – but in a good way! If you haven’t seen a wind farm before, you’ll definitely notice the tall towers above the skyline. But they’re all painted a colour called ‘Turbine Grey’ to help them blend into the background, and in real life, we think you’ll find that wind turbines make the landscape pretty interesting.  

Narrator one: What about the animals and birds? 

Narrator two: Land used for wind farms can still be used for farming, so cows, sheep, goats, bees and the rest, don’t need to worry.  They’re typically not affected by wind turbines and will graze around the bases. Wind farms do pose a risk to birds though. So, when we’re looking for places to build new wind farms, we make sure to take their habitats and migratory patterns into consideration and do our best not to affect them. 

Narrator one: Answering questions and providing reassurance is just one way that we give back to our local communities. It’s important to us that we support them other ways too.  

Narrator two: Through our Power Up Community Funds, we’re able to provide funding for local projects that encourage life-long learning and sustainable initiatives.  

Narrator one: In Aotearoa, approximately 85% of the energy we generate comes from renewable sources and it’s the country’s goal to make that 100% by 2030. At Meridian, we’re doing our bit by generating energy from only 100% renewable resources. We’ve already got some pretty spectacular hydro stations and wind farms; and we aren’t stopping there. As you’ve seen, we’re already building our next wind farm, Harapaki, and looking to expand the ways that we use solar technology to harness the sun’s power.  

Narrator two: We want to ensure that our planet is able to be enjoyed for generations to come and we believe that generating energy from wind, water and sun is our best way forward.