Consider a national-champion utility or independent power producer running a multi-site solar-and-wind build programme. Capex is over plan, EPC contractors are passing through commodity-price spikes, and the original contracting strategy was written before the price environment changed. Use this playbook to frame the work, sequence the analysis, and avoid the common traps in a brief like that.
The consulting question
Large renewables programmes built before the 2022–24 commodity cycle were typically contracted under fixed-price EPC structures that assumed flat input prices. When module and turbine prices moved, the contracts opened up. EPCs renegotiated; owners had limited leverage; the budget drifted. The brief is not to redesign the engineering — that is fine — but to redesign the contracting and cost-control model.
How to approach it
Diagnose the contract economics, not just the engineering. Three weeks reading the EPC contracts, the change-order log, and the as-built variance against design. The cost story is almost always in the contract terms, not the technical execution.
Rebuild the contracting strategy by site cohort. Sites at different stages of construction need different interventions. Pre-FID sites get the new contracting model from the start. Mid-construction sites get targeted renegotiation. Late-stage sites get tightened cost control rather than contract change.
Move from fixed-price to hybrid structures. Pure fixed-price EPC is dead under price volatility. A hybrid structure with pass-through on a defined commodity basket, capped by ceiling and floor, restores predictability for both sides.
Tighten the change-order pipeline. Most cost overruns are not surprises; they are change orders approved without enough scrutiny. Rebuild the change-order governance so material changes get senior sign-off, not procedural sign-off.
Suggested workplan
Weeks 1–4: Contract and cost diagnostic. Site-cohort classification. Identification of the most expensive cost-control gaps.
Months 2–4: Renegotiation of the priority sites. New change-order governance live. EPC commercial team partnered into the cost-control process.
Months 5–9: New contracting standard applied to upcoming sites. Capex variance tracked against the new baseline weekly, not quarterly.
Questions to pressure-test
- What share of the overrun is genuine commodity-price exposure versus contract weakness?
- Where in the construction lifecycle are the worst variances accumulating?
- What leverage does the owner have on each EPC — and where is the relationship worth preserving?
- Is the change-order process producing decisions or rubber-stamping?
- Who in the owner team has the EPC commercial expertise to run this after external support ends?
A strong answer includes
Cost variance closes within a reasonable band. The contracting strategy holds up under price volatility, not just stable prices. EPC relationships are tighter, not adversarial. The owner's cost-control team can run the new governance without external support.
Common traps
The contract is the lever, not the engineering. Engineering teams want to optimise design. The bigger lever is almost always in the commercial terms.
Change-order governance is where the leak is. Most overruns accrue one change order at a time.
EPC relationships matter. Owners who treat the renegotiation as adversarial lose the next round of bids. The framing is "both sides need this to be sustainable."
Hybrid contracts need internal capability. The owner needs commercial people who can run pass-through math live, not annually.
Use this playbook when a renewables build programme is losing cost discipline. It helps consultants test EPC incentives, commodity exposure, owner capability, and cost-control governance.