Trends in construction

One of the most prominent trends in the wind construction sector is moving toward low-cost providers without giving up experience. Also, with the experience many companies now have, each is developing its own approach to constructing quality farms faster. It’s no surprise that specialized software assists with this task. Lastly, the greatest challenge facing the construction sector will be learning to build offshore.

Dave Hart, wind energy manager at Michels Corp., says last year his company saw the first low-cost providers winning bids. However, he explains low-cost bids can often mean higher risks, because providers don’t have adequate experience. “Some companies make it seem like they’re reducing costs through construction management, but in reality these lower costs mean higher risk. This is because the scope-of-work changes from their bid to actual execution against schedule and specification.” In other words, many companies were winning projects because of their low bids, but failed to execute the work they promised. Many low-bid companies lack experience, which could lead to longer and more expensive projects. Developers this year realize they need to find a medium between quality and cost.

The good news is that now many companies are experienced in wind-farm construction. For instance, Mortensen Construction just finished its 100th project, after 16 years in the industry. Jerry Grundtner, VP of project development, says this experience has lead companies to form their own approaches to building. “We take a continuous improvement approach, focusing on efficiency and increased productivity to reduce cost and construction time,” he says. On the other hand, Hart says his company focuses on executing all work internally against schedule and specification to minimize risk, cost increases, and schedule lag.

Another trend involves designing wind farms to satisfy a variety of constraints. “The ultimate goal is to maximize energy capture while minimizing wind loads on turbines and balance-of-plant costs. Yet, we must maintain all setback and avoidance criteria,” says Jay Haley with EAPC Wind. He says this is accomplished with wind software options such as WindPro. Another area where wind-farm designing has gone high-tech is in fluid-flow simulations and lab experiments. Researchers at Johns Hopkins and Belgium’s Leuven University used these methods to study how turbine blades distort wind, creating eddies and turbulence that can affect other turbines farther downwind. This is especially problematic as turbines and farms in general, trend larger. As a result, researchers have developed a model to calculate best turbine spacing.

Finally, as the U.S. continues with offshore development, construction methods will have to adapt. Joel Whitman, CEO of Global Marine Energy Inc., speaks from an offshore cable perspective. “Take a Cape Wind-sized project, for example,” he says. “Its total cost is about $2 billion with the cable install work about 7% of that. Double that figure for supplies as well. So about 15% of all costs are cable related,” he says. The offshore wind industry will have to face cabling issues, while having to use special vessels and work in a short weather window. But Whitman, sees these challenges as not insurmountable and says the industry is moving in the right direction.

WPE