When it comes to wind operations maintenance, more often than not the focus is directed towards the turbines themselves. Gearboxes, generators, rotors and control systems inside the turbine receive the most attention from O&M teams while the Balance of Plant (BOP) can sometimes be an afterthought. This oversight can cause big problems.
Can you spot the problem in this blog photo? Look carefully, and you can see that shackle pin is precariously backed out of its hole. If it falls, the wire drops, an outage could result, and the entire park could be taken off line. Little pin, big problem.
BOP elements – the infrastructure that connects power generating assets to the grid – are vital to the longevity and effectiveness of the assets. They consist of pad mount transformers, underground collection systems, substations and high voltage transmission interconnects, hardly the picturesque components of any wind farm! Due to its static nature, the transmission system is often the most overlooked. The reality, however, is that a minor equipment defect or installation error in this part of the network can result in a failure that could potentially take your entire site offline, costing the owner a very large sum of money. For this reason, it is vital that owner/operators be proactive in their transmission maintenance strategy and execute a specialized plan that is tailored specifically for their system.
The nature of transmission infrastructure is highly variable in design, materials and geography. As a result, it is difficult to devise a comprehensive, BOP included project management plan that will cover all scenarios. Here are several key questions that engineering and maintenance teams need to be asking before they create and implement their plan:
What kind of weather factors will my line be subject to?
Combined ice and wind events can wreak havoc on overhead transmission lines. Is your line prone to galloping during these extreme storms? Do you operate in a moisture rich location which could exacerbate wood pole decay or corrosion on steel poles?
What kind of structures/equipment make up my system?
Are you managing wood, steel, or concrete towers? Polymer or ceramic insulators? Different material types have different modes of failure and as such require very specific inspections and repair methods, such as UAV inspection or NDT inspection.
How long has the current equipment been in service?
Entropy is a ruthless enemy when it comes to BOP infrastructure and your strategy must evolve as the age or your equipment increases.
How accessible is the terrain?
Right of way (ROW) access and availability is critical to what kind of strategy should be employed. Certain inspection methods are more tailored for difficult to reach areas. The costs of unplanned outages can increase exponentially when access is difficult or limited.
An owner must be in tune with all of these factors as they decide what kind of plant inspection methods and frequency they should employ. Once inspections are completed, the question then becomes how will you manage all of your data and turn it into actionable insight on your system? And finally, what are the most appropriate and cost-effective repair/replace options for the specific issues and challenges you are facing?
Answering these questions puts you well on your way toward making sure that one cotter pin doesn’t cost you millions.