The case for greater use of LiDAR technology in wind developments

A LiDAR unit on site in New South Wales

Meteorological masts – often referred to as ‘met masts’ – have traditionally held the key to bankable onshore wind projects. But can Light Detection and Ranging (LiDAR) technology increase wind monitoring accuracy and certainty?

The foundation for a successful wind farm isn’t just concrete pads. It’s accurate wind monitoring data.

Wind project developers need to be able to collect, sort and interpret this data to predict wind speeds, forecast the lifespan of wind turbines, and earn the confidence of investors.

The challenge is: accurate and comprehensive data isn’t easy to collect. The onshore wind industry mostly uses meteorological masts - which are often over 100 metres high - to measure wind speeds, air pressure and turbulence intensity at heights nearer to the wind turbine hub and swept area. But they have limitations, too.

It's unlikely that met masts will be replaced any time soon. However, Santiago Rabelin, our Development Manager – Wind and Site, recently detailed our growing use of LiDAR technology for wind monitoring in the early stages of wind developments at a ZX Lidars Masterclass in Melbourne.

Here are four key takings from Santiago’s masterclass.

Santiago Rabelin, Development Manager - Wind and Site

Flexibility is the primary benefit of LiDAR technology

LiDAR systems are highly portable remote sensing devices, so we can tow them to various locations across a site on a trailer within a day. LiDAR technology uses laser beams to measure wind speed and direction at multiple heights by tracking aerosols – which are solid or liquid particles moving through the air.

This makes LiDAR units much more flexible than fixed met masts, which need strong foundations to support their 100-150 metre height. This means they’re not practical to move in short timeframes.

We’ve found the flexibility of LiDAR technology to be invaluable in complex terrain. A single LiDAR unit can be moved around a site to map out wind flows across varying landscapes, providing data that would be impractical or prohibitively expensive to obtain with multiple met masts.

LiDAR technology paints a broader picture of wind speeds

Santiago noted that LiDAR technology can capture wind data up to 300 meters in height, covering the entire rotor swept area of modern turbines. This is particularly useful because wind turbines are getting taller, with longer blades than older units.

LiDAR technology therefore provides a more complete picture of wind conditions at critical hub and blade tip heights, covering heights that most met masts can’t reach.

LiDAR technology reduces impacts on surrounding communities

Met masts are tall structures, so they are clearly visible to the human eye in surrounding areas. Because of this height, they require extensive engagement with nearby communities, who need to be informed about visual changes to their landscapes.

By contrast, LiDAR units are no taller than an average trailer, so their visual impacts over long distances are negligible. As Santiago explained, this is a key advantage because developers can do wind monitoring in more areas with less of an impact on surrounding communities. Particularly in the very early stages of a development.

A hybrid approach provides the greatest certainty for all stakeholders

Santiago concluded that using a combination of LiDAR technology and met masts is the most effective approach to capture accurate data at all heights and various locations, while gaining the confidence of investors.

There is currently no replacement for the financial backing and long-term warranties essential for a bankable project, which come from the proven and direct measurements of a met mast with monitoring equipment much nearer to the hub height of the turbine.

But by leveraging the strengths of both technologies – and exploring greater use of LiDAR units for wind monitoring - developers can see the fullest picture of the future viability of a wind farm.