Burns & McDonnell

Little Things Add Up in Successful Solar Construction

Written by Chad Cotter | December 4, 2019

Solar construction may look simple enough to the untrained eye. Such projects certainly appear at first glance to be less complicated than, say, a large combined-cycle natural gas-fired power plant. Just set up a bunch of panels and point them at the sun, right?

But solar photovoltaic (PV) projects come with plenty of their own challenges. As an integrated firm providing engineering, direct-hire construction and other consulting services, we have seen and avoided a lot of the potential pitfalls. Being able to draw on multidisciplinary resources gives us numerous insights that can make the difference between a good project and a great one for a utility or independent power producer.

Knowing the Lay of the Land

Before the design work even begins, it is important to perform due diligence on the environmental front. Complacency during that process can lead to issues around migratory birds, threatened or endangered species, or wetlands delineation that would have negative impacts on the project budget and schedule.

Developers must not neglect what lies just below the surface, either. The solar arrays will be constructed on foundations, but how deep do they need to be? Accurately determining that depth is an early step that can have a significant impact on cost.

A geotechnical analysis is important, but its value depends on making sure the right number of samples are being taken and that the analysis is tested practically to see that the necessary accuracy has been achieved. A 200-megawatt solar site might easily cover 500 acres. Drilling three holes the size of a coffee cup is not going to help establish a representative picture of the full site. You need enough borings to develop an appropriate theory, because an inaccurate understanding from limited sampling can lead to additional scope and expense later on. Once the site theory is established, we would order some posts, drive them into the ground, then push and pull on them to confirm the analysis. This helps the developer avoid spending too much by making foundations too deep, or leaving foundations too shallow and having to make very costly adjustments later.

Managing Time and Talent

The ongoing stepdown in the solar investment tax credit (ITC) is fueling a lot of activity in the market as developers race to procure panels, inverters and other materials and lock in a better ITC rate. As a practical matter, the tight supply — especially in the panel market — can complicate project planning because of the limited availability.

Careful solar project management cannot make panel production any faster — there is no magic wand. But it can involve setting up factory visits and making sure products are moving through the line in a timely fashion without sacrificing quality for schedule.

A critical consideration when contemplating a solar construction project is an understanding of the state of the local labor market. The renewable energy market is booming, and projects are getting ever bigger. A solar construction effort requires a lot of craft labor. If the project site is in a remote area, it’s essential to plan for the travel, per diem and other retention costs that might be necessary to obtain sufficient labor.

Putting It All Together

We’ve seen that one of the most valuable techniques in starting the construction phases is building a mockup row. Essentially, one row is built, and then everyone comes in to evaluate and critique it. A lot of potential project snags can be caught and addressed by taking the time for a pause at that early point.

The mockup row also presents an opportunity to establish best practices for the site among a core group of laborers. They can then be dispersed across the full construction effort to share any lessons learned from the mockup row; wisdom gained on the site is arguably worth more than all the drawings and instructions one could provide.

With all the complexities involved in any construction effort, there are countless details across numerous disciplines that need to — or at least should — be harnessed to deliver an efficient, successful project. An integrated project delivery approach brings all those pieces together so that every i gets dotted and every t is crossed on the way to deploying your solar arrays.

 

Know more about the key factors for successful solar construction efforts, including how to maneuver in a changing marketplace.