Article - Greenbyte

Four reasons why you should focus more on wind measurements

Measuring the wind is an obvious first step to developing a wind farm. Unlike a conventional power plant where fuel is transported to it, the fuel for a wind farm must be discovered and quantified. This is why many refer to the early stage as wind prospecting.

Measuring the wind is an obvious first step to developing a wind farm. Unlike a conventional power plant where fuel is transported to it, the fuel for a wind farm must be discovered and quantified. This is why many refer to the early stage as wind prospecting. 

Let’s take a big picture view of why one needs to do a thorough wind resource assessment. Measuring the bare minimum to secure a bank loan is not enough. Mistakes or overestimations can have ripple effects lasting more than 20 years over the life of the wind farm. After construction, wind turbines cannot feasibly be moved to another site. 

A wind developer should understand and accept that they are measuring the wind for four different parties. These parties have different perspectives and requirements. 

Wind Power Developers

First, the developer is measuring for themselves. Which sites are the most promising? How much power can be produced on each site? What is the estimated annual energy production (AEP)? A cost conscious developer can cut some corners depending on their level of risk tolerance. As examples, they could choose to measure for only 12 months instead of 2-3 years, or they could opt to measure with met masts below hub height and extrapolate wind conditions above the mast. 

Wind Power Investors

Second, the developer is measuring for those with the capital: lenders, investors and financial institutions. Like anyone making a loan, they will be careful where they put their money and will always err on the side of conservatism. Poor or insufficient wind measurements can result in higher uncertainty scores. Higher uncertainty leads to higher borrowing costs and/or requirements to continue wind measurements. It is important to note that financial institutions typically do not have in-house experience to judge wind farm proposals in technical detail. Therefore they rely on experienced wind consultants, so the developer is in effect measuring to satisfy the wind consultants. Wind development is a very international industry and frequently the investors and consultants are not in the same country as the wind project locations. Consultants thoroughly review record keeping, calibration reports and maintenance logs with a critical eye.

Turbine Manufacturers

Third, the developer will need to provide wind data to the turbine manufacturer. The manufacturer will be responsible for a warranty period and a warranted power curve. Different turbines have different operating characteristics and site conditions can stress the turbines, e.g. ice, heat, turbulence, shear, storms. The turbine manufacturer can refuse to sell a turbine which they believe to be inappropriate for the site. The manufacturer will also be interested in wind speeds across the entire blade sweep area, from lowest point to highest tip point. For these reasons, the turbine manufacturer may require LIDAR or SODAR remote sensing data to measure above the met mast. This cost is typically borne by the developer and can add additional months to the wind study. Incorporating remote sensors earlier in the development process will save time. 

Authorities

Finally, in some countries, developers will need to provide wind data to governmental authorities either during the pre-construction process or on an ongoing basis to meet forecasting requirements for grid stability. Developers should investigate these requirements from the outset. 

The days of juggling Excel spreadsheets on an office PC are nearly over. Systems which perpetuate handwritten maintenance logs,  lost calibration reports and irregular data backups are long past due for an overhaul. The stakes are simply too high. The degree of professionalism and organization required today to run multiple simultaneous wind studies with multiple data formats from multiple geographic areas demands a far more powerful software system.

With these parameters in mind, take a look at web-based scalable professional Breeze Development.