The engineering context
What the assignment needs to resolve
A CBG EPC contract turns a verified project basis into an operating facility through engineering, procurement and construction. The term turnkey only becomes meaningful when the battery limits, owner responsibilities, utilities and acceptance conditions are explicit. Land, grid connection, transport equipment and statutory responsibilities must be identified even where they sit outside the EPC price.
Execution planning connects design releases to manufacturing, civil readiness, delivery, installation and commissioning. A plant can be mechanically complete while feedstock arrangements, power availability or the gas buyer interface are still incomplete. Those external dependencies need to be visible in the programme from the start.
From project basis to operating handover
| Gate | What should be ready | Why it matters |
|---|---|---|
| Design release | Approved mass balance, layout, package duties and interface list | Procurement follows an agreed basis |
| Manufacturing release | Drawings, materials, inspection plan and acceptance requirements | Inspection points are built into vendor schedules |
| Site installation | Civil readiness, access, foundations and utility interfaces | Avoids delivery damage and repeated handling |
| Commissioning | Safe systems, calibrated instruments, trained team and start-up plan | Mechanical completion becomes controlled operation |
| Performance acceptance | Agreed feed, stable conditions, measurement boundary and test duration | Output, gas quality and consumption can be assessed fairly |
Altpreneur scope
How we approach the work
Engineering
Develop the process layout and coordinate civil, mechanical, piping, electrical and instrumentation packages. Confirm maintainability, material handling and emergency access.
Procurement
Place equipment orders against approved duties and specifications. Manage vendor drawings, inspection points, logistics and long-lead items.
Construction and installation
Sequence foundations, structures, equipment erection, piping and electrical works with site readiness and quality documentation.
Commissioning and handover
Complete mechanical checks, functional trials, biological start-up and gas-quality validation. Conduct performance testing against the agreed feedstock and operating conditions.
Decisions worth getting right
Distinguish trial operation from guaranteed performance
A short demonstration of gas generation does not establish sustained output. The acceptance protocol should define the averaging period, inlet conditions, allowable interruptions and correction method.
Use a scope matrix alongside the price
For every interface, identify who designs, supplies, installs, tests and maintains it. This reduces disputes about gaps that are not apparent in a summary machinery list.
Prepare the operating handover
As-built drawings, equipment manuals, spare lists, calibration records, emergency procedures and training records are operating assets. Their delivery should be tracked with the physical works.
Assignment outputs
What you receive
- Approved engineering and procurement packages
- Construction and installation records
- Commissioning procedures and test reports
- As-built information, operating manuals and training
- Handover and defect-closure documentation
To begin
Useful starting information
- Site possession and land details
- Approved capacity and feedstock basis
- Utility, offtake and financing status
- Client/EPC responsibility boundaries
Scope and responsibility
Land, utility connections, statutory fees, transportation assets, working capital and taxes require explicit allocation. Biological stabilisation and performance tests need agreed feedstock quality and client readiness.
Common questions
Does turnkey mean every expense is included?
Only the signed scope defines inclusion. Offsite utilities, land, fees, gas logistics and taxes should be individually addressed.
Can a plant guarantee be unconditional?
Performance must refer to measurable feedstock quality, quantity, utility availability, operating hours, gas quality and test duration.
Evidence & further reading
Source material
- US EPA AgSTAR: Project Development Handbook
- US EPA AgSTAR: Anaerobic Digester/Biogas System Operator Guidebook
Technical references inform the discussion. Final design, operating limits and policy eligibility depend on the project and applicable current documents.