HomeMy WebLinkAboutA007 - October 28, 2025, Regular Meeting of the Ames City CouncilITEM #:10
DATE:10-28-25
DEPT:ELEC
SUBJECT:COMBUSTION TURBINE CONTROLS UPGRADE - CHANGE ORDER NO. 1
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(CT2) are outdated and are in need of replacement.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 must 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.
The most effective method of replacement is by swapping out the electrical "buckets".
Replacement buckets were obtained from the OEM, Eaton, following approval of City Council
at the February 13, 2024 meeting. These buckets have been received and will be installed
concurrently with the controls update to CT1. With the buckets and supporting documentation
delivered, the specification was finalized and prepared for the proposal process.
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.
THIS ACTION:
The following additional beneficial changes to the proposed combustion turbine controls
system have been identified as the project entered initial design.
1) Petrotech has identified additional controls equipment that should be replaced
during this project, including remote Input/Output equipment inside a cabinet located
on the engine enclosure. Replacement of this equipment will ensure additional
reliability of the entire system. This addition will cost an extra $34,980.44, inclusive of sales
tax.
2) Petrotech has also proposed that the controls systems for both CT1 and CT2 will
function more effectively in a centralized network architecture. A centralized network
architecture will provide: 1) improved generating asset reliability by employing a redundant
server in case of primary server failure, 2) better security and access control by centrally
managing user permissions, 3) enhanced performance by reducing local workstation
processing, and 4) simpler system maintenance by hosting all applications on a single server
that is accessible at any workstation.
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The servers for this centralized architecture will be hosted in the CT2 control room. Locating
the servers in the CT2 control room will enable the Combustion Turbine site to operate locally
in case of communication loss with the Steam Electric Plant control room and continue the
functionality of the data historian. This addition will cost an extra $139,320.42, inclusive of
sales tax.
Change Order No. 1, in the amount of $174,300.86, will be necessary to implement these
improvements. The current CIP includes a total of $2,850,000 in funds available to perform
the combustion turbine controls upgrades. There is currently $1,218,293 available to fund this
change order. Staff does not foresee additional expenses for the project at this time.
ALTERNATIVES:
1. Approve Change Order No. 1 with Petrotech Inc., of New Orleans, LA, for Combustion
Turbine Controls Upgrade in an amount of $174,300.86.
2. Do not approve the change order.
CITY MANAGER'S RECOMMENDED ACTION:
Change Order No. 1 consists of two changes to the proposed combustion turbine
controls system. The additional controls equipment for CT2 will ensure higher reliability
of the entire system. A centralized network architecture will enable Electric Department
staff to more effectively control and maintain Combustion Turbines 1 and 2. The
centralized network architecture will increase reliability of the CTs, improve system
security, enhance controls system performance, allow for simpler controls system
maintenance, and enable greater controls system functionality during emergency
situations. Therefore, it is the recommendation of the City Manager that the City Council
adopt Alternative No. 1 as stated above.
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