Wind farm control as an industry wide opportunity
When analysing the wind energy industry with a complexity informed mindset, a few interesting points emerge. Technical innovations have sparked a reflexive effect in the industry. The increased reliability and reduction in the levelised cost of wind energy have strengthened the trust of policy makers and stakeholders, and therefore, the sums of investment. These factors have generated a virtuous circle of wind energy dissemination around the world. On the opposite side, the confirmation of wind as a reliable source of energy has recently driven a reduction in subsidy levels and increased the need to push for further cost reduction.
When economic challenges arise, a general trend towards protecting added value in the overall industrial chain appears in various forms. The drive for cost competition is pushing manufacturers to strictly safeguard the knowledge of turbine technology to keep secret the source of their competitive advantage. Owners and operators who search for ways to cut costs and improve the performance of their assets to maximise the revenue generated, are increasingly developing turbine related knowledge, skills and tools.
One question arises on whether recent innovations in control technologies can support the industry in achieving higher competitive targets. We are probably closer than we have ever been to benefitting from industry wide innovation, thanks to the latest research and development effort on wind farm control. Recent studies and research validation have shown encouraging signs of development with wind farm control techniques, offering the potential to positively affect both the machines manufacturing and the planning and operational side of the industry.
Wind farm control strategies can be set using benefit functions to decide whether to offset the operating conditions towards energy production or mechanical loads reduction on the machines. It’s easy to imagine how this could work as a sharing platform for turbine manufacturers, wind farm owners and operators to jointly decide which side of the optimisation problem to prioritise.
Hopefully the old approach of turbine suitability where machines are selected based on a pass/non-pass principle will be soon obsolete. Alongside the luxury of selecting operational strategies, a few more benefits can be gained by working with induction control and wake steering techniques.
Analytical tools recently developed enable the industry to study the effect of wakes on farm energy production and loading regime with intuitive outcomes for operational decisions. One of the solutions will make it possible to choose whether to spread the damage evenly on the fleet or to “sacrifice” a few machines. What sounds like a simple solution poses in reality a few complicated physical problems. Considering the changing direction of the wind and its effect on different turbines, combined with wake interactions, mechanical loading and energy production, are just a few factors to study.
Quite a lot can be gained by conquering control of the entire wind farm, including the capability to better serve grid needs with an array of ancillary services, such as reactive power, fast frequency response, curtailment, ramp & delta control, to mention a few. In an ideal scenario, wind farm control could also be considered in the pre-construction phase to decide machine layout and selection in function of how the farm could be operated.
As with any exciting engineering problem, a few technical challenges are still unsolved and validation is one of them. When the benefit at stake is a few percentage points of annual energy production and a better control on the machines’ loading regime, an industry wide effort to explore the potential benefits and limitations is justified. In this respect, the role of wind turbines manufacturers, wind farms owners and operators, alongside technical experts, should convene to share knowledge and effort for the good of the industry.