Repowering an existing combined-cycle power plant involves far more than replacing gas turbines. Existing steam systems, cooling infrastructure, balance-of-plant equipment and project execution risks must be evaluated before significant capital commitments are made.

PRIOS was engaged to perform an owner-side techno-commercial assessment of a 133 MW combined-cycle power plant in West Africa as part of an ongoing repowering initiative.

The objective was to establish a realistic technical and commercial basis for future project development while identifying critical risks and technical interfaces at an early stage.

Project Background

The existing facility had experienced prolonged operational challenges and was evaluating a repowering strategy involving the replacement of the original gas turbine fleet with modern gas turbine technology (GE Frame 5 gas turbines).

The project aimed to improve plant reliability, operational availability and long-term economic performance while maximizing the use of existing infrastructure and installed assets.

As with many power plant rehabilitation projects, a number of technical, operational and commercial assumptions required validation before further project development could proceed.

PRIOS was therefore engaged to perform an independent owner-side assessment supporting the project's early-stage decision-making process.

Why Early Repowering Assessments Matter

Many power plant rehabilitation and repowering projects encounter delays, cost overruns and technical challenges because critical assumptions are not challenged early enough.

Replacing gas turbines is only one element of a successful repowering project. Steam turbine capability, cooling systems, electrical integration, auxiliary equipment, operational constraints and construction sequencing must also be considered.

Independent owner-side assessments help identify technical and commercial risks before detailed engineering, procurement and construction activities begin.

This significantly improves decision quality and reduces project uncertainty during subsequent development phases.

Scope of Assessment

PRIOS performed an owner-side assessment covering:

• Existing plant configuration review
• Gas turbine replacement evaluation
• Steam cycle impact assessment
• Cooling system review
• Balance-of-plant assessment
• Technical interface identification
• Discussions with OEMs and contractors
• Project execution risk review
• Techno-commercial evaluation
• Development strategy support

The assessment focused on establishing a realistic understanding of the opportunities, limitations and implementation challenges associated with the proposed repowering concept.

Key Findings

The assessment confirmed that the proposed repowering concept has the potential to significantly improve plant reliability and long-term operability.

However, several technical interfaces required further evaluation, including:

• Steam turbine integration
• Cooling system capacity and replacement with modern fin fan coolers
• Auxiliary system modifications
• Construction sequencing
• Operational integration requirements

The early identification of these considerations reduced project uncertainty and established a clearer basis for future development decisions.

Outcome

The assessment established a structured technical and commercial baseline for future project development.

Key technical interfaces, implementation risks and project constraints were identified at an early stage, enabling informed decision-making before major engineering and procurement commitments were undertaken.

By validating critical assumptions and highlighting priority focus areas, project stakeholders were able to proceed with greater confidence and a significantly improved understanding of project execution requirements.

Services Provided

• Power Plant Repowering Assessment
• Technical Due Diligence
• Owner's Engineering
• Techno-Commercial Evaluation
• Project Development Support
• Risk Identification & Mitigation
• Power Generation Advisory

About PRIOS

PRIOS supports owners, investors and project developers in the evaluation, acquisition, rehabilitation, relocation and development of complex industrial assets worldwide.

The company combines technical understanding, commercial structuring and execution expertise to support informed decision-making throughout the project lifecycle.