How to structure this contract
- Split by asset type. Solar, wind, transmission, substations, and water do not share a cost structure.
- Check which components have a real index. Transformers and switchgear are the strongest indexed components.
- Index transmission and substations directly. Use those two series plus metals and labor inputs.
- Build composites for the rest. Solar, wind, and water have no matching domestic index.
Split the contract by asset type
A solar farm, a wind farm, a transmission line, and a water treatment plant do not share a cost structure. Solar and wind pricing follows global equipment markets and tariffs. Transmission and substations follow metal and electrical-equipment prices. Water infrastructure follows civil construction. Treat each as its own price adjustment model, not one blended formula.
Solar and wind
No single domestic government index captures solar module or wind turbine prices. Those prices are set globally and move with manufacturing capacity and trade tariffs, not with what one country's producers charge. Build the formula from real cost components instead.
| Component | Benchmark | Note |
|---|---|---|
| Module or turbine cost | NREL or SEIA cost trend reports | Industry benchmark, not a government index |
| Mounting structures and towers | PCU331110331110 (steel) or WPU102501 (aluminum mill shapes) | Match to the actual material |
| Installation labor | Regional construction wage index | |
| Transport | Freight index | Oversized turbine components are expensive to move, and freight swings can outweigh the equipment cost itself |
Transmission and distribution
Two of the biggest cost drivers here have real, live BLS indices: transformers (PCU335311335311) and switchgear (PCU335313335313). Both update monthly. Add a metals index for conductors, typically WPU102501 (Aluminum Mill Shapes) for aluminum conductors, and a construction wage index for installation labor.
There is no reliable government index for "power line construction" as a finished output. A series that would appear to fit this, NAICS 237130, returns no data when checked directly against the BLS API. Treat that gap as a composite, not a benchmark.
Substations and grid equipment
Substations mostly reuse the same two indexed components as transmission: transformers (PCU335311335311) and switchgear (PCU335313335313). Add site civil works, typically benchmarked with PCU327320327320 for concrete products, plus skilled electrical installation labor.
This is the strongest indexed sub-sector in energy infrastructure, because transformers and switchgear are both real manufactured products with real, live price surveys behind them.
Water infrastructure
Water treatment plants, pipelines, and pumping stations are civil construction projects first. Construction materials and labor usually matter more than the mechanical equipment.
The pump equipment index is published under an aggregated industry code, PCU33391-33391- (Pump and Compressor Manufacturing), not a standalone product-level series. Confirm it is still live at bls.gov/ppi before naming it in a contract, since BLS does retire and restructure specific series codes over time. Use a general construction cost index for the civil work, and price pumps against this industry-level series or a negotiated cost baseline if the aggregated code is too broad for the scope.
Don't index solar or wind to a domestic PPI
Module and turbine costs are set by global supply and tariffs, not by what one country's producers charge. A domestic manufacturing index will drift away from what you actually pay within a few review cycles.
Live index data
- US PPI: Power, Distribution, and Specialty Transformer Manufacturing: current value, year-over-year change, and a free calculator
- US PPI: Switchgear and Switchboard Apparatus Manufacturing: current value, year-over-year change, and a free calculator