Case Study — Infrastructure
EV Charging Infrastructure Electrical Estimate — Atlanta, GA
Project Overview
Electrical estimate for a large-scale EV charging infrastructure project at a mixed-use commercial campus in the Atlanta Perimeter area. The project included 750 Level 2 charging stations across (4) parking decks and (2) surface lots. Scope included: new 4800A 480V service from Georgia Power with 8MW service upgrade, (6) 2000A distribution switchboards, (30) 100A subpanels for charging station distribution, (12) 225kVA step-down transformers, complete DAS/extender system for cellular coverage in parking decks, charging station pedestal installation with concrete curbing and bollards, load management system with 750-station load shedding controller, and utility-grade metering for each of 750 stations.
CSI MasterFormat Divisions Covered
26 05 00, 26 05 13, 26 05 33, 26 08 00, 26 12 00, 26 22 00, 26 24 00, 26 27 13, 26 32 00, 33 71 00, 33 79 00
Estimating Challenges
- Georgia Power required an 8MW service upgrade with 28-week transformer lead time — the existing campus service was 2000A at 277/480V and could not support even the minimum charging load
- The (4) parking decks were built in 1985, 1992, 1998, and 2005 — each had different structural constraints, existing electrical systems, and asbestos-containing fireproofing that affected conduit routing
- Load management system integration required communication wiring (fiber, Cat 6A) to each charging station across 6 buildings — the data backbone cost ($340,000) was initially underestimated
- The owner wanted 750 stations visible in a single software dashboard but the station manufacturers had not been selected yet — the estimate had to include provisional allowances for 3 different OCPP-compatible systems with cost ranges
Change Order Prevention
During the takeoff review process, our team identified the following scope gaps that would have become change orders if not caught at the estimating stage:
- Identified that parking deck #2 (1992) had only 100A spare capacity in its existing panelboard — the charging infrastructure required 600A — new feeder from the main switchboard required ($34,000)
- Caught that the bollard and curbing installation for surface lot stations required coordination with the existing stormwater drainage — (4) station locations were in drainage swales that required relocation — ($9,000)
- Flagged that the cellular DAS system required separate fire alarm interface in each parking deck stairwell — not shown in any scope — ($16,000)
Labor Forecasting
Applied infrastructure project labor factors per NECA MLU with 20% productivity reduction for parking deck work (low headroom, confined spaces, existing occupancy). Atlanta IBEW LU 613 rates. The project required 6 distinct mobilizations across the campus — allowed $28,000 for demobilization/remobilization. Parking deck work restricted to off-hours (8 PM-5 AM) for decks with overnight tenant parking — applied 1.3x night shift premium for 40% of the work.
Material Escalation Strategy
The Georgia Power 8MW transformer upgrade was the single largest cost item at $1.2M — firm pricing obtained with a 30-day acceptance window and 4% escalation protection beyond 6 months. Charging station hardware (750 units) was not procurable without manufacturer selection — included a 10% escalation allowance on the hardware line item. Copper feeder quantities were significant (parking deck risers) — locked with quarterly re-pricing.
Budget Comparison
| Line Item | Initial Estimate | Final Bid | Variance |
|---|---|---|---|
| Utility Service Upgrade | $1,450,000 | $1,510,000 | +4.1% |
| Distribution & Switchboards | $980,000 | $1,018,000 | +3.9% |
| Charging Station Hardware | $1,875,000 | $1,988,000 | +6.0% |
| Data & Communications | $340,000 | $362,000 | +6.5% |
| Civil (bollards, curbing, trench) | $420,000 | $446,000 | +6.2% |
| Labor & Commissioning | $930,000 | $976,000 | +4.9% |
| Total | $5,895,000 | $6,200,000 | +5.2% |
Risk Mitigation
Recommended the owner select charging station hardware within 60 days of award to lock in pricing and confirm OCPP compatibility requirements. Also recommended a single campus-wide fiber backbone installation rather than building-by-building connections — this approach saved $48,000 in redundant infrastructure. Coordinated with Georgia Power at week 1 on the 8MW service upgrade to establish the 28-week transformer timeline and avoid critical path conflict.
Result
The project was awarded at $6.1M. The 8MW service upgrade was completed on the Georgia Power 28-week schedule without delays. The 750 stations were commissioned over a 10-week rolling schedule. Post-project analysis showed electrical change orders totaling $42,000 — all for owner-requested charging station relocations after the initial layout was finalized.