Design and detailed documentation is the engineering backbone of any power project. The chain ETS → design documentation (PD) → detailed documentation (RD) defines turbine type and rating, the thermal scheme, machine hall layout, grid connection and energy-efficiency measures. A mistake here costs an order of magnitude more than at any later stage. This article explains the difference between the three stages, the required input data, timelines, cost drivers and the expert review process.

Design stages of a power project: input data, ETS, design documentation, expert review, detailed documentation, designer supervision
Fig. 1. Design stages of a power project, from input data to detailed documentation and designer supervision.

Context: why the topic matters

ETS (essential technical solutions) is pre-design work: equipment type and ratings, the principal thermal and electrical schemes and a feasibility and cost estimate. Design documentation (PD) is the "P" stage whose composition is set by Government Decree No. 87; it undergoes expert review and approval. Detailed documentation (RD) is the "R" stage that turns approved solutions into working drawings and specifications for procurement and installation.

StageWhat it isPurpose
ETSEssential technical solutions, investment justificationDefine the object and assess feasibility and budget
PDDesign documentation by sectionsPass expert review and obtain a construction permit
RDDetailed documentation: drawings, specificationsEnable procurement, manufacturing and installation

Key parameters and selection criteria

Project quality depends on the completeness of input data: site data (master plan, surveys), technology (turbine/generator type, steam parameters, thermal scheme), power data (load profiles, grid connection) and constraints (safety authorities, reliability category, energy-efficiency law). Missing data should be marked "to be confirmed via the questionnaire" rather than assumed.

Composition of design documentation sections under Government Decree No. 87
Fig. 2. Composition of design documentation sections under Government Decree No. 87. Sections 5 and 6 are key for power objects.

Mind the standard revisions. GOST R 21.101-2020 was withdrawn on 1 April 2026 and replaced by GOST R 21.101-2026. Always verify the current revision before issuing documentation.

Expert review flow of design documentation
Fig. 3. Expert review of design documentation and issuance of a positive conclusion.
Indicative timeline of power project design stages
Fig. 4. Indicative timeline of design stages; values are illustrative and depend on the object.
Cost drivers of design and detailed documentation
Fig. 5. What drives the cost of design and detailed documentation. Exact price is quoted per object.

Common client mistakes

  • Incomplete input data and missing surveys.
  • Ordering only PD without RD, blocking the start of installation.
  • Using outdated standard revisions, causing rejection at expert review.
  • Blurred responsibility boundaries between client and contractor.
  • Unrealistic timelines without parallel stages.

Practical scenarios

New captive generation, reconstruction/modernization and capacity expansion each place different demands on ETS, PD and RD. Equipment selection relies on our steam turbines, turbo-generators and condensers lines; real figures are in our case studies.

Request checklist

Input-data checklist for a design documentation request
Fig. 6. Input-data checklist for a design request: site, technology, power and constraints.

Ready to discuss your project? Send your input data and questionnaire and we will estimate the scope, timeline and cost. Request a design cost estimate →

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