Appoint a Detailed Engineer when you need someone to produce the design; appoint an Owner's Engineer when you need someone to check it on your behalf. The Detailed Engineer is accountable for the engineering. The Owner's Engineer is accountable to the owner for reviewing that engineering, the equipment and the construction. The same firm should not do both on one Project.
Key Takeaways
- Detailed Engineer: produces design, calculations and drawings.
- Owner's Engineer: reviews, oversees and recommends acceptance for the owner.
- Independent Engineer: provides an impartial view, often for authorities or lenders.
- Independence matters — the reviewer should not have produced the work.
The Detailed Engineer
Usually appointed by the EPC Contractor, the Detailed Engineer turns the design basis into construction-ready engineering: studies, calculations, drawings, equipment specifications and site support. Their obligation runs to the party that appointed them and to the construction programme.
The Owner's Engineer
Appointed by the asset owner or developer, the Owner's Engineer protects the owner's technical interests: reviewing feasibility and grid studies, the EPC's design, vendor selection and factory tests, overseeing construction quality and witnessing commissioning before performance is accepted.
The Independent Engineer
Government bodies, PSUs and concession parties often need an impartial technical view against a contract. The Independent Engineer reviews, inspects and documents technical acceptance recommendations that both sides can rely on.
Why One Firm Should Not Do Both
A reviewer who produced the work cannot review it independently. Elegrow does not act as Detailed Engineer and as Owner's or Independent Engineer on the same Project.
When to Appoint
The Owner's Engineer adds most value early — at feasibility, when sizing and connection decisions set cost and performance for decades — but can join at any Project Stage.
Frequently Asked Questions
Is an Owner's Engineer the same as a lender's engineer?
Not necessarily. An Owner's Engineer represents the owner. A lender's or Independent Engineer represents a party that needs an impartial view.
Can the EPC's designer also witness the tests?
They can take part, but independent test witnessing for the owner should be done by a party that did not produce the design.
