Utility Scale Solar 3D Site Profile

7 Ways a Digital-First Approach Improves Utility-Scale Solar Economics

In Industry Perspectives by info@pvcomplete.com

When it comes to utility-scale solar project development, careful analysis and optimization to ensure the project economics pencil out is critical to mitigate risk, ensure project bankability and realize return. For the first time, with the introduction of the PVSketch Mega and PVCAD Mega “Mega Suite”, developers now have powerful digital tools at their fingertips to quantitatively inform portfolio decisions. 

PVComplete’s Mega Suite makes possible seven project economic advantages, as illustrated by this sample project at 14235 Sample Road.

12345 Sample Road Utility-Scale PV Site

As you can see, it’s a large field that includes typical tree lines, roads and obstructions with a rough capacity of 40 MWs. 

 Advantage #1: Site Prospecting

Before making decisions about equipment or site configuration, the first consideration is the site itself. Today, there are a number of options for accessing digital topography data. Prospecting the site by leveraging these general slope tolerances allows remote, early assessment of a sites viability. 

For the Sample Avenue site, we’ve imported a location image and topography in order to calculate what we call the “rackability” — or the percentage of usable space based on sloped tolerances and other keep out areas.

Evaluating the terrain and exclusion zones, PVSketch Mega creates a 3D profile of the topography and corresponding keep out areas based on specified tolerances. The Sample Road site has ~516,100 meters2 of usable space, which is 72% of the total plot.

3D profile of the topography and corresponding keep out areas

Advantage #2: Mounting System Selection

Using the Mega Suite, we can also analytically evaluate mounting system options for both fixed tilt and single axis tracker projects. Because the software automates layout configuration, it’s possible to generate any number of configurations featuring different manufacturers for comparison. This capability allows developers to choose a mounting system that best meets project goals. As we all know, some trackers and fixed tilt systems are better suited to uneven terrain. With PVSketch Mega, users are able to select and consider multiple mounting options in tandem while optimizing the design configurations.

Side by Side Mounting System Comparison

At the Sample Avenue site, PVCAD Mega shows fully realized layouts compared side by side in the  dialogue box on the right which lists project specifications, including system size, basic production values ,the number of trackers and exposures for each version of the design. This view makes it easy to compare basic project specs associated with each racking manufacturer.

Advantage #3: Material Costs

Material costs are one of the biggest considerations in project economics. To inform material cost reductions, PVCAD Mega surpasses traditional slope analysis with a much more sophisticated pier analysis. Rather than simply consider a general slope tolerance, pier analysis evaluates every pier and automatically plots and sizes each post to the requirements of its unique site location and underlying terrain. This results in better estimates, less steel and lower material costs than could be realized if all piers were manufactured to a uniform height. The more varied the project terrain, the more impactful the upfront analysis will be.

The table below shows a PVCAD Mega automated pier schedule for the Sample Avenue site. The highlighted column includes the calculated height for each individual pier — meaning that the sum of that column equals the total amount of steel required for the entire project, specific to the topography and the array configuration.

Utility-Scale Solar Project Pier Schedule

Both PVCAD Mega and PVSketch Mega also create an automated Bill of Materials (BOM) to assess material costs by  quantifying trackers and tables based on exposure categories and size. Using the auto-generated BOMs for each possible tracker configuration allows a quantitative comparison between layouts based on the number of partial trackers, exterior exposure trackers and other configuration elements that might add additional material costs. 

Utility-Scale Solar Project Bill of Materials

The digital-first approach is a data-rich approach, making it a powerful tool for project developers.  

Advantage #4: Grading

Because topo and pier analyses allow for a more accurate evaluation of post height, utility-scale project developers can now determine with certainty how material costs for either greater post-height and/or stronger foundations compare with the cost of site grading. 

PVSketch Mega easily assesses where grading will be required. In the image below of the Sample Avenue site, PVSketch Mega recognizes the location and size of the site area that should be considered for grading or adjusted mounting.

Utility-Scale Project Grading Diagram

Additionally, in the PVCAD Mega-generated fixed tilt layout below, we can see the analyzed contour lines and affected tables highlighted in red. With this information, you can compute the number of piers that are affected. We can also run a pier analysis with adjusted tolerances to assess possible routes to mitigate grading. By identifying problem areas and the affected piers and tables or trackers, it is easy to compute cost differences for a more informed plan moving forward.

Utility-Scale Solar Site Contour Lines

Advantage #5: GCR, kW Output & Production Values

PVSketch Mega makes it easy to determine how modifying key system components affects system design and performance estimates, including module choice, various tilt angles, DC to AC ratios, and module orientation. The software assesses these effects by computing ground coverage ratio, kilowatt output, capacity, and production values. Using software to compute these values is increasingly common, but until now these calculations were typically run using separate, free-standing tools that required significant manual data input and cross-referencing. Now, PVSketch Mega provides a single platform to measure these key performance indicators automatically. 

For maximum precision, the Mega Suite makes it possible to compare outputs from different production calculators — including PVWatts, PVSyst and Canadian Solar’s Cassys model — which can be referenced directly within our applications. The energy production example below illustrates how easy it is to select and control project components in real-time to see how they affect key indicators of system performance.

Utility-Scale Energy Model

Advantage #6: Constructability

Further along the project life cycle is construction. Because automated pier analysis sizes every post to spec, it’s possible to eliminate post-height-related slowdowns during project construction.  It eliminates false positives (mistakenly determining that a site is constructible when it is not) which require  on-site adjustments like costly unanticipated grading or custom foundation rework. 

The added accuracy of pier analysis versus traditional slope analysis also eliminates false negatives (dismissing a trackers or tables because it appears outside of tolerances) that cause lost capacity from your initial design. PVCAD Mega adjusting pier location and tracker foot print specific to the underlying terrain This ensures each pier calculation is extremely accurate and every inch of space can be used. 

Additionally PVCAD Mega creates 3D renderings of elevated project designs providing context to crews before even breaking ground and eliminating costly surprises once at the site. 

In the 3D profile of Sample Avenue below, we’ve placed every single pier according to the unique post heights specified earlier on the pier schedule. All of these heights are actually recorded for easy reference and use as well in an auto-created pier schedule.

Utility Scale Solar 3D Site Profile


Advantage #7: Optimization

Much of what we’ve discussed so far contributes to project optimization, but the Mega Suite can advance project optimization even further by doing the heavy lifting for developers and eliminating manual recording and output comparison for separate production calculations and layout tools. PVSketch Mega and PVCAD Mega consolidate all of this information on one platform to succinctly run and compare all iterations. For large-scale solar projects, it used to be that designing for every possible outcome was unrealistic. But the Mega Suite is a game-changer that allows developers to pick a site configuration based on target system size, kWh production or levelized cost of energy. 

The image below shows the optimization results generated by PVSketch Mega based on our project goal of a 40 MW system size and our ground coverage ratio and tracker configuration limitations. Every possible outcome is auto-calculated and displayed in the table below with project specs. And the graph above each dot on the chart is a layout using a different GCR or mounting system for easy visualization as to how the different configurations stack up against one other.

Any of these configurations can then be rendered automatically and viewed to help developers move onto the next phase of their project design.

Utility Scale Solar GCR Optimization Graph

We’ve entered into a new era in utility-scale project development where it is possible to leverage digital-first approaches for site prospecting, mounting system selection, material cost reduction, grading decisions, performance estimates, constructability and overall project optimization. As solar projects become larger and are installed on increasingly varied terrain, digital, data-driven tools are necessary to realize a greater return and maximize utility-scale solar economics in an increasingly competitive and growing industry.