Solar construction is helping states meet aggressive clean energy targets
Drew Powers
in Connect on LinkedIn
At the start of 2021, the solar market remains strong. As U.S. states and utilities work toward their decarbonization goals — some of which have target dates rapidly approaching — replacing coal-fired power plants with renewables such as solar has become increasingly more important for generation fleets. The two-year extension of current solar investment tax credit (ITC) percentages also will increase interest in building solar projects with additional time to take advantage of tax credits.
According to the U.S. Energy Information Administration, power plant owners and developers are anticipating almost 40 gigawatts (GW) of new electricity generating capacity in 2021, with solar representing the largest share of new capacity at 39%. Also beneficial, solar costs are projected to continue to decline as technology advances and market participation increases.
For more on what’s happening with solar, hear from construction manager Drew Powers, who is currently working as site project manager for CenterPoint Energy’s 65-megawatt direct current (DC) Troy solar plant in Southwestern Indiana. With more than 12 years of experience in construction, he’s well-versed in project execution and well aware of where the market is headed and the challenges and solutions associated with it.
Q: What should utility owners consider when looking at solar sites?
A: There are many details that owners should consider when it comes to selecting a site. First off, location, location, location is key to the success of the project as it is with all real estate investments. Proximity to established roadways is critical for access to the project site as well as to an existing overhead transmission line and/or substation for collection and transmission of generated power. Also, site civil work — including clearing and grubbing and extensive site grading — is required for the site to be usable for solar construction.
Geographical constraints could necessitate additional acreage to achieve the desired plant output, which could extend into nonproduction space, such as drainage ditches, creeks, retention and detention basins, and utility corridors. Additionally, geotechnical constraints, if not considered upfront, pose construction challenges, including poor soils that would require increased pile design, rock that would require pre-drilling or alternative foundation design, soil corrosivity and thermal resistance. Environmental constraints also need to be considered early, because each jurisdiction has rules regarding wetlands, flood plains, threatened and endangered species, and more.
Q: What are the challenges associated with craft labor for solar projects?
A: Solar construction is still relatively new across the country; therefore, craft labor training on solar-specific tasks is one of the biggest challenges. Most craft labor personnel have training in their core competencies but need specific training on such solar-specific tasks with solar-specific tools. Providing pertinent safety and installation training is critical to the success of the project.
Task complacency is another challenge. Craft laborers are assigned a specific task, which might be completed repeatedly throughout the duration of the project. Alternating tasks among an experienced crew minimizes complacency and incident exposure.
Q: How is technology used to improve solar construction?
A: Burns & McDonnell is implementing technology through the design and construction of our solar sites. Drone imagery and mapping is used to obtain preliminary topography information, allowing the site civil design team to conduct preliminary site assessment, and acquire civil as-built data used for piling data development. Pairing data developed during the civil or structural design phase with GPS-equipped pile driving equipment improves efficiencies in pile driving, while drone imagery also can be used for progress documentation. Additionally, we have utilized and continue to explore the use of powered exoskeletons to assist with critical repetitive tasks. While on-site, we use mobile applications for safety, daily reporting, quality forms and more.
Q: What benefits can an integrated engineer-procure-construct (EPC) contractor provide?
A: An integrated EPC contractor brings considerable cost and schedule efficiencies to any project and, ultimately, the owner, especially when armed with the capability to execute all phases of a solar project, including the solar photovoltaics (PV) and interconnection substation. By working simultaneously on design, procurement and construction, an integrated EPC contractor has a full-service team that’s able to design, procure and mobilize quicker than a traditional design-bid-build delivery method or niche construction company can. Integrated EPC execution also allows for the construction team to be involved in the design phase to provide constructability review and address any potential conflicts during the design phase rather than during construction. The sooner that we can get involved to assist a client with the site selection, development, permitting, design and site optimization, the more streamlined the process and beneficial for the owner.
Q: What are other frequently asked questions about solar construction?
A: We often get asked what the best time is to bring in a project delivery partner. The answer is the earlier, the better. Having a collaborative team that’s all in from the beginning provides exceptional value throughout each phase of the project. Our inclusive team has experience in all phases of project development, including cost analysis and preliminary design, project siting, permitting, right-of-way and easement acquisition, and transmission studies. While we can execute a range of delivery approaches, EPC delivery is our preferred method, providing the client with one point of accountability, cost certainty and a quicker project timeline.
On the technical side, we also get asked about using bifacial versus monofacial modules. Bifacial modules produce solar power from both sides of the panel and have higher efficiency ratings but require special equipment. The traditional, time-tested monofacial modules, on the other hand, produce solar power from one side and don’t require special mounting equipment. Deciding which modules to use requires further discussions about client project output goals, capital expenditure, module lead time and tracker manufacturer.
Yes, the solar industry certainly remains a bright spot within the construction industry. “A total of 9.5 gigawatts direct current (GWdc) of new utility photovoltaic power purchase agreements were announced in Q3 2020, bringing the contracted utility-scale solar pipeline to a record total of 69 GW,” as stated in the Solar Energy Industries Association’s U.S. solar market insight. With more than 107 GWdc of installations expected within the next five years, solar will have a large presence in our future, helping utilities diversify their energy portfolios and reduce their carbon footprints.
With solar technology costs dropping and decarbonization targets approaching — as well as a two-year extension on the solar ITC — interest in solar is at an all-time high. Learn how contractor knowledge and experience in the current, ever-changing marketplace not only helps overcome challenges but also advances the development of new utility-scale solar farms.