Solar and battery storage developers spend enormous energy chasing deals to put megawatts on the grid. Site acquisition teams model annual production, interconnection queues get scrutinized, and financing packages get built around a preliminary layout drawn from public data. Yet, too often, projects run into cost overruns, delays, or are canceled entirely.
What often gets forgotten in this early rush is the project’s constructability: whether the project, as designed, can actually get built on schedule and on budget in the field. Constructability covers the ease and efficiency of executing a project, from grading and access roads to cable routing and equipment placement.
Issues left unresolved at the concept stage rarely stay small—they surface later, and often with larger repercussions. Fixing the problem later virtually always costs more, as redesigns, permitting delays, and change orders add to the substantial investment the developer has already made on a site with a low probability of successful execution.
Topography and site access are two fairly easy risk mitigation exercises that will point out problems with projects before they balloon, giving developers a chance to either back out or troubleshoot as needed. The most important piece to remember is that early planning solves problems before they start.
Topography Establishes Groundwork For All Sites
Preliminary layouts almost always draw from publicly available elevation data, typically only known at 5-foot or 10-foot contour intervals. That resolution works fine for a rough feasibility check, but for sites with complex terrain, dense forestation, or proximity to floodplains, the gap between assumed and actual grade can quietly undermine an entire design.
A detailed topographic survey, ideally at 2-foot contour intervals or finer, closes that gap and gives engineers the data they need to work with and design for. Once that data feeds into CAD, a proper slope analysis can identify problem areas before they become expensive ones.
This step pulls in civil, structural, and electrical engineers alongside construction professionals and racking vendors, since grading, racking tolerances, drainage, and conductor routing all depend on the same terrain data and need to be reconciled together rather than sequentially.
Skipping this step or doing it too late will have consequences later: racking that doesn’t meet vendor slope tolerances, stormwater pooling near equipment pads, and access roads that need mid-construction rework. Topography touches nearly every downstream design decision, so it’s a poor place to cut corners.
Site Access Carries More Risk Than Most Think at the Outset
Layout discussions tend to focus on maximizing module count and DC-to-AC ratio. Access, meanwhile, gets treated as a given, an assumption that breaks down fast once a project moves toward construction.
Even a site adjacent to a paved road can hide obstacles: steep approach grades that need retaining walls, stream crossings that trigger hydraulic analysis, utility crossings that add design complexity, or local DOT requirements for turn lanes and driveway permits. Large trucks, some carrying oversized equipment, need adequate turning radius at the entrance.
If any of these factors don’t magically fit into the site specs and local government regulations, retrofitting an approach after the fact eats directly into schedule and budget, and in some cases will eat into DC capacity of the project.
The access road itself can have similar pitfalls. A design built for construction, operations, and safety accommodates two-way traffic for heavy trucks, includes turnarounds where the site demands them, and routes cleanly to laydown and long-term O&M areas. Following natural contours where possible reduces earthwork, and early geotechnical work heads off surprises in soils prone to expansion, bedrock, or high groundwater.
In addition to access roads, temporary equipment laydown areas should be incorporated into the design so that deliveries can be successfully, efficiently, and safely conducted. Laydown areas will be heavily trafficked, so they should be flat and have temporary gravel put down so they stay as dry as possible and don’t break down over construction.
Medium-voltage (MV) routing adds another layer of complexity. Overhead lines cost less per foot and install faster in soft or forested terrain compared to underground, but can trigger FAA filings near airports and more extensive tree clearing. Permitting and long-term maintenance. Underground lines cut visual impact and add protection but come with higher trenching costs and longer material lead times.
Co-locating MV routing along the access road, where feasible, consolidates disturbed area and can meaningfully reduce permitting scope on either path.
Equipment pad siting needs to minimize DC home run distances, account for voltage drop at the 30% design stage, avoid low-lying areas prone to pooling or flooding, and stay accessible for maintenance vehicles, emergency responders, and crane access for future transformer or BESS replacement. None of these variables work in isolation, and leaving these details for last tends to produce a pad location that fails on at least one count.
Wetlands and hydrology don’t impact every project, but they often are the headline issues when relevant, and without granular topographical data on site, they are even harder to design around. Developers that don’t properly prioritize wetland delineation often end up with equipment or roads sited in flood-prone areas, jurisdictional buffer conflicts, or trench and road rerouting well after the design has been finalized and approved by relevant parties.
Engaging wetland consultants and developing a stormwater prevention plan alongside the preliminary layout, rather than after it, avoids most of this.
Building Constructability in From the Start
None of these considerations demand elaborate engineering, but they require sequencing and foresight: pulling topographic survey, access planning, MV routing, and environmental review into the same early conversation that currently belongs almost entirely to module layout and yield estimates.
Developers who build this discipline into their process avoid the costliest failures in solar and storage development, when a design works on the computer screen but not once construction teams mobilize in the field.
The alternative, catching these issues during construction or after financial close, costs far more in time, money, and credibility than addressing them at the outset. Constructability belongs inside the design process from the first site walk, and projects that treat it that way tend to be the ones that get built on schedule, on budget, and as promised.
—Mark Warner is a project manager for Camelot Energy Group.
