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John T. Duff, P.E.Joh Duff ST Power Services

Consultant, Duff Power Services, LLC


John Duff is an independent consultant at Duff Power Services, LLC (“DPS”) that has teamed with ST Power Services (“STS”) to provide comprehensive OEM and customer perspective to the optimization of life cycle combustion turbine maintenance programs and client strategic portfolio management.

John has over 40 years of experience in power generation as both an owner-operator and as an aftermarket service provider. John’s experience in both regulated and unregulated power generation provides the customer perspective in assessing, developing, implementing and managing combustion turbine life cycle maintenance programs utilizing OEM or aftermarket parts and service providers. Securing approval and acceptance of internal and external stakeholders including executive management, board of directors, lender’s independent engineers, credit rating agencies (Moody’s and Standard & Poor’s), and property insurance carriers, as applicable, is key to program success. Once approval and stakeholder acceptance are secured, the program can be taken to market through a bid process utilizing scoping and performance specifications, bidder list development, bid evaluations, life cycle cash flow projections, capital parts life cycle cost, business plan stress testing and final contract negotiations and execution. Ongoing program management cost optimization can be through either external Asset Management services or internal client self-management with the necessary training, planning tools and parts models provided as part of an implementation program.

As STS provides the OEM perspective and DPS provides the client perspective, the collaboration provides the client with an optimized and custom tailored major maintenance program to minimize life cycle cost with acceptable risk to meet particular business objectives.

Experience Highlights:

Tampa Electric Company:
Sixteen years of experience, at 4,000 MW regulated electric utility, with progressively increasing responsibilities including coal power plant performance testing and improvements, various plant manager roles, management of a central machine shop for steam turbine repairs, company wide warehousing and spare parts consolidations and service improvements, union contract negotiations and plant manager of a 1,200 MW coal power plant.
While at Tampa Electric, John served as project manager responsible for environmental licensing, site development, fuel procurement, fuel supply, transmission system interconnection, regulatory interface, governmental agency interface and public relations for a 250 MW commercial scale utility integrated gasification combined cycle (IGCC) power station.

TECO Power Services Inc.:
As Vice President, responsibilities included the mobilization, operation and maintenance, asset management, technical due diligence and asset condition assessment for power plant acquisitions, development support and environmental licensing and compliance of a domestic and international independent power generation portfolio which expanded to 10 plants totaling 7,000 MW.
The fleet consisted of 22 F class operating gas turbines and the negotiation or renegotiation of OEM LTSA agreements on 27 operating and development stage turbines.

TECO-Panda Generating Company:
As President, John was responsible for the management and direction of the ownership transfer of 4400 MW of power generation assets with an installed cost of $3 billion to the non-recourse lender group. Position responsibilities included: serving as the senior executive with fiduciary responsibility to project creditors during the insolvency period; representing the debtor in the pre-arranged Chapter 11 bankruptcy; managing the day to day plant operations, accounting, and trading risk management functions; resolving outstanding construction warranty claims; and developing and implementing the insurance program, employee benefit programs, payroll system, and human resources policies and procedures.

Entegra Power Group, LLC:
As Senior Vice President, John was responsible for strategic leadership and direction of the power plant operations and maintenance, engineering, capital projects, environmental, human resources and corporate insurance functions for a privately owned independent power generation and energy trading company with a portfolio of 4400 MW (F class turbines), annual revenues of $600 million, annual O&M budget of $30 million and a two year major maintenance budget of $67 million. This position interacted with owners, lenders, rating agencies, environmental agencies, community and local governmental leaders, state political leaders in addition to participation in board of director meetings. John successfully developed and implemented an aftermarket gas turbine maintenance program that generated savings in excess of $80 million (or 60%) from the prior long-term contract.

Power Generation Service Providers:
As President – North America Industrial Gas Turbine Business Unit for Gas Turbine Efficiency, LLC, John was responsible for the startup and operation of an E and F class field service operation and for an F class combustion repair facility.
As Director of Sales & Commercial Operations for the Dresser-Rand Industrial Gas Turbine (IGT) business unit, John was responsible for North America sales, the development and implementation of the global IGT business unit long-range plan, a long term bundled maintenance outage services commercial infrastructure, a new and refurbished parts business, IGT marketing, new product development and power plant project development.

Duff Power Services, LLC:

  • Managed a LTSA bid process for two (2) new F class gas turbines for a peaking plant in Texas including bid document preparation, bid clarifications, preliminary commercial negotiations and development of a life cycle cash flow projection.
  • Managed a LTSA bid process for two (2) 7FA.03 gas turbines removed from storage for a peaking plant in Texas including bid document preparation, bidder qualification, bid clarifications, bid evaluations, life cycle cash flow projections, short list bidder selection recommendation, manage commercial negotiations to final contract documents, negotiation of a non OEM gas turbine performance guarantee and warranty, and life cycle cash flow projections.
  • Conducted a fleet major maintenance program assessment for a confidential client to develop life cycle cost projections for renewal of the current OEM program or for development and implementation a self-managed major maintenance program utilizing aftermarket parts and service providers.
    Conducted hourly market value modeling for ERCOT, PJM, MISO and CAISO to determine the market value of incremental capacity in support of new product development and deployment strategy.
  • Authored two (2) papers on the economics of upgrading existing combustion turbine output as compared to new build generation and on the economics of various schedule-firming technologies for renewable generation.
  • Presented keynote speeches at two (2) gas turbine user conferences on the challenges facing the power generation market and strategies for success in an uncertain future.





  • Gas Turbine Major Maintenance Program Development & Implementation
  • LTSA Bid Process Management, Bid Evaluation, Negotiation & Execution
  • Energy Market Analysis & Valuation
  • Project Development
  • Customer and Stakeholder Program Acceptance


  • 40 Years in Power Industry
  • Plant Manager
  • VP O&M & Engineering
  • President - Field Services & Combustion Repairs
  • Consultant


  • University of Tampa: Master of Business Administration
  • Georgia Institute of Technology:Bachelor of Mechanical Engineering
  • Jacksonville University: Bachelor of Science in Physics and Mathematics

Professional Affiliations

  • American Society of Mechanical Engineering
  • State of Florida:Professional Engineer
  • FM Global Customer Advisory Board: Former Member

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