Solutions / Engineering guide
Wind Turbine Supply vs Turnkey: Project Responsibilities
“Supply only” and “turnkey” are commercial labels that need a detailed project boundary. Define the equipment, work, output condition and responsible parties behind each label. A turbine delivery is not evidence that all local engineering and construction tasks have been included.
Assign each deliverable and each interface.
Build a responsibility map around the actual scope, including the work between suppliers that otherwise has no clear owner.
01 / Equipment package
Separate the supplied objects from project work.
List the turbine assembly, controller, converter and accessories with quantities and configuration identities.
List the turbine assembly, controller, converter and accessories with quantities and configuration identities. State whether a tower is in the same offer, supplied through another party or outside the proposal. A component list answers what arrives; it does not answer who designs the installation.
MARSTON can discuss turbines, controllers and converters as separate purchases and coordinate with tower suppliers. This does not establish an all-inclusive construction or turnkey service. The DOE Small Wind Guidebook provides background on the equipment and installation support involved in a small wind project.
02 / Design ownership
Give combined-system decisions a named owner.
Assign responsibility for site suitability, tower and foundation design, electrical interfaces and the required output service.
Assign responsibility for site suitability, tower and foundation design, electrical interfaces and the required output service. Identify the information each designer needs from the equipment suppliers. A tower drawing alone cannot settle foundation conditions or the site’s electrical requirements.
One useful record names the design item, input provider, responsible designer, reviewer and release condition. If the controller and converter are sourced separately, identify who reviews their interaction with the turbine and site supply. No universal third-party compatibility should be assumed.
03 / Delivery boundary
Distinguish receipt from readiness for construction.
Define where equipment is delivered and who receives it.
Define where equipment is delivered and who receives it. Record whether packaging, transport legs, unloading, storage and onward movement are within the offer. A stated destination needs a physical receiving point and an agreed responsibility boundary.
Keep these logistics duties separate from construction mobilisation. The presence of equipment on site does not establish a prepared foundation, available installer or permission to begin work. Use the delivery-term guide for the transport allocation.
04 / Site execution
Allocate civil, mechanical and electrical work.
Identify the local parties responsible for site preparation, tower erection, electrical installation and coordination with other facilities.
Identify the local parties responsible for site preparation, tower erection, electrical installation and coordination with other facilities. Record their scope and required equipment information without creating installation procedures. These responsibilities may sit outside the turbine supplier’s boundary.
Check gaps between contracts: a civil contractor may complete the foundation while an installer expects another party to verify its interfaces. Capture the deliverable and review needed at that handoff. A broad “installation included” label is insufficient if the included work remains undefined.
05 / Completion state
Define what acceptance actually covers.
State whether the agreed endpoint is equipment receipt, completed installation, a defined commissioning record or another documented condition.
State whether the agreed endpoint is equipment receipt, completed installation, a defined commissioning record or another documented condition. Separate equipment conformity from complete-system acceptance. Each endpoint needs its applicable configuration, evidence and responsible sign-off party.
Do not equate acceptance with an annual-energy result or guaranteed uninterrupted supply. A project can meet an agreed delivery milestone while operating performance remains subject to resource and site conditions. Keep outstanding owner duties and third-party dependencies alongside the completion record.
06 / Support boundary
Keep later responsibilities visible before purchase.
Name who holds the final documentation, reports faults, arranges local access and supplies ongoing service within the actual agreement.
Name who holds the final documentation, reports faults, arranges local access and supplies ongoing service within the actual agreement. Separate supplier technical communication from a confirmed local maintenance contract. Neither should be inferred from the word “turnkey”.
A useful enquiry states the requested supply scope and the buyer’s existing local design and installation team. Unassigned work can then be discussed explicitly. This guide does not promise MARSTON construction, storage, a worldwide installer network or responsibility for every project stage.
Continue the review with Wind Turbine Technical Bids: Compare the Same Supply Scope.
Continue the review with Wind Project Delivery Terms & Installation Responsibilities.
Continue the review with Wind Project Operator Handover & Training Scope.
General background: DOE Small Wind Guidebook: equipment comparison and supplier questions. These references explain industry concepts; they are separate from the applicable MARSTON product and project documents.
Prepare the information for this review.
Use the checklist to organise the project information. Mark unavailable items and retain document references.
| Review item | Information to provide | Purpose |
|---|---|---|
| Supplied objects | Assembly identities, quantities and accessory scope | Define what arrives. |
| Engineering roles | Input provider, designer, reviewer and release condition | Assign interface decisions. |
| Logistics endpoint | Named receiving point and transport responsibilities | Separate delivery from site readiness. |
| Completion scope | Agreed condition, evidence and accepting party | Define the project handover. |
| Support ownership | Document custodian, local access and service agreement | Keep ongoing duties explicit. |
Engineering questions.
Does supply only include a complete installation?
Only the actual agreement establishes included work; the label itself does not.
Does turnkey prove annual energy or continuous supply?
No. Delivery scope and operating performance need separate definitions and evidence.
Can electrical equipment be purchased separately?
Yes, separate enquiries are possible, with combined-system interface review still required.
Does tower coordination include foundation design?
Do not assume that. Identify the tower and civil designers’ actual responsibilities.
Who reviews interfaces between different suppliers?
Name the responsible project designer or integrator in the scope map.
What closes a scope gap?
A defined deliverable, assigned party and agreed review or completion condition.
Technical enquiry
Bring your project information to the discussion.
“Supply only” and “turnkey” are commercial labels that need a detailed project boundary. Share the available information and the equipment scope you want reviewed in a technical quotation.