How do you estimate the optimal duration and cost of FEED for your project?

For any FEED project it is utmost important to have clear understanding of Client requirements.These requirements not only means current requirements but also future provisions, when such requirements are clear FEED becomes comprehensive & more cost effective. Optimal duration of FEED depends upon the scope involved like feasibility study, Capex-opex calculations , new specifications generation, site surveys requirement, green field or brown field project etc. Optimal cost of FEED really difficult to give a thumb rule but FEED will be value for money when we have clear definition of Client requirements.

- Based on my experience; I fully agree with the defining of the project scope as the very first step. Also a project charter to be provided with the Project Statement and obtaining all project stakeholders sign off’s on the project charter require to be the 2nd very important step.

That is absolutely correct to have a defined project scope in coordination with the project stakeholder and should provide a clear Project Matrix/ SOW with sign-off's.

I totally agree with performing a feasibility study content and steps and along the way keeping all the records with all of the key assumptions in a key document register.

Work Breakdown Structure is very handy and useful when it comes to big EPC projects. it will help in defining the packages, roles and responsibilities and help you in assigning the necessary and required resources. Also you can keep track of the same on later stage to monitor your progress or a change.

Sadly two of the biggest risks are scope creep by the client and lack of accurate documentation. Many estimates are made assuming the documents are correct often over the years on older plants. I've found - not marked up at the end of the last job, a quick change made during shutdown, A whole new DCS being wired in to the old cabinets with no documentation, wiring change due to fire, abandoned equipment in the field, undocumented equipment, power supplies sources moved due to loading, misfiling of documents, many time I need to search the maintenance shacks to find markups they use as its not in records. My point is tracing out all these issues takes way more time than anyone wishes to admit and someone else takes the blame.

we have a bad habit in estimating, that we assume what worked the last few times should work again. I've learned even if installations look the same on paper, they may not be. Remember the hours you put down, some needs to do the job in. Not the hours you think you need to put down to get the bid. You make the company look bad if it cant be done in the hours you select. Ive had leads demand the minimum hours we would need to do the job so I gave them. They then cut them in halve and gave them to the client assuming I added in fat.We came in slightly over the hours I indicated but 2x what the client expected.