CSLB C-46 Solar ContractorPlanning and EstimatingHard
A C-46 contractor is developing an estimate for a large-scale commercial ground-mounted PV system. The project site is characterized by uneven terrain and significant changes in elevation. Which estimating consideration will likely have the most substantial impact on the overall project cost for site preparation?
- AThe cost of fencing for security around the array.
- BThe expense of geotechnical surveys for foundation design.
- CThe price variation of PV modules from different manufacturers.
- DThe costs associated with extensive grading and leveling.
Show answer & explanationAnswer & explanation
Correct answer: D. The costs associated with extensive grading and leveling.
Uneven terrain and significant elevation changes on a large-scale project necessitate extensive earthwork, including cut-and-fill operations (grading and leveling). These activities involve heavy machinery, large labor forces, and potentially importing/exporting soil, making them extremely costly and often the most substantial component of site preparation for ground-mounted systems on challenging topography.
Why the other options are wrong
- A. Fencing adds cost but is typically a fixed or easily estimated cost, less variable than earthwork for uneven terrain.
- B. Geotechnical surveys are necessary but are a one-time, upfront cost, not a recurring or highly variable construction cost like grading.
- C. Module prices are a major system cost but are not part of 'site preparation' and are less directly impacted by uneven terrain than earthwork.
Ground-Mount Site Prep Cost Drivers
For ground-mounted PV on uneven terrain, extensive grading and leveling are the primary cost drivers during site preparation due to significant earthwork requirements.
- Uneven terrain requires substantial earthwork (cut/fill).
- Heavy machinery, fuel, and labor are expensive.
- Soil import/export adds to costs.
Memory trick: Uneven land means heavy machines, heavy costs.