Whether you are a project developer or an EPC, balancing risks and returns is the crux of any utility PV project. Upstream planning ensures eBOS (electrical balance of system) designs are optimized for maximum production, while efficient execution delivers on your project’s financial targets. When mapping your eBOS strategy, the right mix of up-front customization and downstream problem-solving will help ensure your project’s profitability.
Cut installation time and risks with bespoke wire solutions
One key differentiator to improve time-on-site is to deploy prefabricated wire solutions tailored for your project that will integrate easily in the field. Prefabricating custom harnesses and source circuit lengths as well as adding connectors and performing wire stripping in advance serve to slash installation effort in the field. It is crucial for wire solutions to be built to factory-controlled tolerances to guarantee higher quality and longevity.
Prefabricated and customized wire solutions offer multiple benefits:
● Ensure consistency and durability during factory manufacturing instead of relying on manual in-field prep and cuts
● Eliminate complexity in the planning and execution phases
● Streamline on-site execution to compress project schedules
● Save cost and contain budgets
Generic, bulk wire solutions that require on-site installation result in higher labor costs and longer equipment rental periods. And because solar installation often brings unplanned issues, a lack of planning usually results in using more wire than needed, wasting time and money. Most importantly, field-fabricated solutions lack the consistency – and quality – of factory-assembled components.
How to scale customized eBOS solutions
Look for prefabricated tailored wire solutions that deliver smarter plug-and-play connections with better upfront planning to streamline installation downstream. Ready-to-go wires that have been packaged and labeled for accurate distribution and installation will go far to reduce labor and time on site.
On paper, wire layout can be planned for maximum efficiency. However, errors in the field can happen during manual crimping, cutting, and installation. Factory-assembled wires come with a level of accuracy that manual processes on site can’t provide. Variables that come from in-field execution such as connector attachment torque, pin crimping, wire strip accuracy, and harness length are controlled in the factory. With a bespoke approach, properly spooled and labeled wires arrive in the field ready for fast, precise installation.
An eBOS partner that delivers 100% in-house assembly gives you enhanced control over quality and lead times compared to providers who subcontract their work. Because of their deep experience, they can leverage unique skills to design project-specific solutions. Their estimators can address project complexity upfront and help uncover opportunities to improve wire layout efficiency early on.
Adding combiner boxes and whips to wire solutions provides a complete dc solution from the modules to the inverter. A clean and well thought-out combiner box design that takes multiple source circuits helps fuse site-specific solutions to meet your unique needs.
Integrated PV partners who own the entire process—from design and supply chain to manufacturing and installation across eBOS and racking—can also achieve higher-quality solutions to fit your project specifications. They understand how variables like topography, height of racking, or number of modules impact wire design. If your eBOS partner also has mechanical racking installation capabilities, they are familiar with solar field operations and maintenance and understand how wiring can impact these activities over the long run.
Lessons from the field
Case study: Custom wiring for agrivoltaic project
Dual-purpose agrivoltaic projects are inherently complex. When a developer in southern Massachusetts planned for a solar-plus-storage system atop a cranberry farm, caution was required to place the panels and wiring carefully over the 150-year-old vines.
Situation: The system’s 9 MW of solar generating capacity and 36 MWH of battery storage had to be installed high enough to prevent damage to the cranberry field and allow for harvesting. The developer turned to Terrasmart to design and build a racking and eBOS solution at an atypical height to minimize impact on crop growth and harvest activities.
Mounting: The solar arrays had to be mounted on 25- to 40-foot-long wooden utility poles resistant to wet terrain. The poles needed to be driven 15 to 30 feet into the ground to keep the trackers at least 10 feet above the cranberry bogs. At this height, significantly more wire was required than was typical for a project that size.
eBOS coordination: Generic, off-the-shelf wire solutions would not work here, especially not within the project’s tight six-week delivery window; typical wire projects have eight- to 12-week timelines. Instead of waiting for the racking system to be completed before installing the wiring, the team coordinated the wiring alongside the racking and panel installations.
Factory-assembled source circuit conductors from Terrasmart — a total of 1,384, with half positive and half negative — were cut to length and labeled in the factory with MC4 connectors installed on the panel end. These were blunt-cut on the opposite end for field connection to Terrasmart combiners. Wiring was shipped on spools to the site with end-to-end connectivity, allowing for quick plug-and-play in the field.
This agrivoltaic project revealed a myriad of eBOS benefits:
- Creative problem-solving up-front resolved installation complexity
- Prefabricated wiring accommodated the atypical heights atop the vines, providing consistent and accurate cut lengths; off-the-shelf, bulk wiring would have not worked
- Wiring integration ease with previously purchased combiner boxes
- Coordination between wiring, racking and module installation shaved weeks off the timeline
- Project execution did not affect the cranberry harvest
The result: A turnkey project strategy that ensured the most optimized wiring solution to meet challenging height, placement, human activity, and project schedule goals.
Joe Parzych oversees the wire division for Terrasmart. With more than 15 million feet of wire installed, Terrasmart offers an integrated eBOS, racking, software, and installation solution combined with a deep understanding of the solar project lifecycle for lower risks and higher returns.
— Solar Builder magazine