HomeMy WebLinkAboutA001 - Council Action Form dated January 13, 2026ITEM #:18
DATE:01-13-26
DEPT:ELEC
SUBJECT:COMBUSTION TURBINE CONTROLS UPGRADE - CHANGE ORDER NO. 2
COUNCIL ACTION FORM
BACKGROUND:
The existing controls systems on Combustion Turbines 1 (CT1) and Combustion Turbine 2
(CT2) are outdated and are in need of replacement. The hardware, software, system
architecture, and several pieces of instrumentation are antiquated; replacements are difficult to
find; and generally the systems no longer reflect best industry practices. Electric Department
staff worked with AP4 Energy Services, LLC to develop a specification for acquiring a
combined, updated controls system for both combustion turbines.
During the development of the specification and review of the existing infrastructure, it was
also determined the existing motor control center (MCC) for CT1 needed to be updated. The
existing MCC utilizes a proprietary communications protocol that is no longer supported by the
manufacturer and replacement parts are difficult to acquire, with only used parts available.
On August 12, 2025, City Council awarded a contract to Petrotech Inc., of New Orleans, LA,
for the Combustion Turbine Controls Upgrade project in the amount of $1,213,252.67.
During the review project after the contract was awarded, the Petrotech recommended that
additional controls needed to be replaced. Therefore, on October 28, 2025, City Council
approved Change Order No. 1, in the amount of $174,300.86, to add additional controls
equipment to the specification and to change the control system to use a centralized network
architecture identified by Petrotech.
THIS ACTION:
Change Order No. 2, in the amount of $176,054.59, will be necessary for replacing
additional control equipment and instrumentation in both CT1 and CT2. A total of five
additional changes are being recommended by Petrotech for the following reasons:
1. Replace the existing expander and generator lubricating oil tank level switch with a
modern level transmitter. The expander and generator lubricating oil tank located in
CT1's auxiliary equipment room is utilizing a level switch instrument which is original to
installation. This switch is well beyond its useful life and requires replacement.
($22,183.24)
2. Replace the original rack-style modules used to relay field information to the central
processor. The current modules are outdated and too large to fit with the other updated
hardware and will be replaced with more compact modules. There is no additional cost
to replace these modules. ($0.00)
3. Replace the servo controller that drives the stator vanes with a new assembly hosted by
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the central processor in the CT2 control room. This will allow for the ability to perform
calibration and maintenance without the need for a laptop with antiquated software.
($15,365.20)
4. Replace the older digital valve positioner (DVP) with a modernized version that still
works with the existing valve body. CT2 utilizes a water injection system to reduce the
nitrous oxides produced during operation. This water injection system has a valve driven
by a DVP to allow the optimal amount of water into the combustion zone. The current
DVP is original to the installation and also requires using an outdated version of
Windows operating system for access. ($40,125.00)
5. Replace seventeen (17) outdated instruments on critical systems. Instrumentation on
CT2 is mostly original to when the asset was installed and commissioned in 2005. Many
of the instruments that are crucial to operation are beyond their useful life cycle and in
need of replacement. A total of sixteen (16) pressure transmitters and one (1) level
transmitter have been identified as critical for replacement. ($98,381.15)
With this action the total contract amount will be $1,563,608.12. There is currently $1,083,992
available in this Capital Improvement Project to fund this change order.
ALTERNATIVES:
1. Approve Change Order No. 2 with Petrotech Inc., of New Orleans, LA, for Combustion
Turbine Controls Upgrade in an amount of $176,054.59 (inclusive of Iowa sales tax).
2. Do not approve the change order.
CITY MANAGER'S RECOMMENDED ACTION:
The Combustion Turbines have antiquated equipment that is difficult to maintain and
replace, causing reliability concerns in critical operating systems. The recommended
changes from Petrotech will enable Power Plant staff to maintain the generating assets
more easily while also replacing sources of reliability concerns, thus increasing the
reliability of the Combustion Turbines. The items listed in this Change Order were not
anticipated during specification development. Therefore, it is the recommendation of the
City Manager that the City Council adopt Alternative No. 1 as stated above.
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