CASE STUDY:TURNING UP THE HEATBRINGS RATCHABURI’S
FUEL COSTS DOWN
US$2.4M A YEAR.

TOMONI®
Performance Improvement
Flexible Operation
IGV Optimization
PLANT DETAILS• Ratchaburi Power Plant• IPP owned by Ratchaburi Power
Company Limited (RPCL) near
Bangkok, Thailand
EQUIPMENT NOTES• 1400 MW Dual Fuel Gas Turbine
Combined Cycle Plant• Mitsubishi Power DIASYS
Netmation® Control Platform• TOMONI Solution Installed:
2015, 2018

CHALLENGE
When the gas turbine combined cycle (GTCC) plant owned by Ratchaburi Power Company Limited (RPCL), an independent
power producer near Bangkok, Thailand, entered service, it was optimized for base-load operation. Within a few years, itbegan to be dispatched a significant amount of time at partial loads and, by 2015, was running 50% of the time below 80%
load. This created a need to improve plant heat rate at part loads on the GTCC. RPCL collaborated with Mitsubishi Powerto find the best solution to improve the efficiency at part loads.
By 2017, RPCL’s dispatch profile had changed again. Although still below full load, it was being dispatched at higherloads than before and in governor control mode most of the time. This resulted in frequent load changes that reduced thebenefits of the original solution. It was clear that a more flexible and comprehensive approach was needed, so Mitsubishi
Power and RPCL worked together to define the most cost-effective approach.

SOLUTIONRESULT

Together, Mitsubishi Power and RPCL
found that the IGV Optimization solution
would increase operation flexibility andallow RPCL to run more efficiently at part load by tuning
the IGV (inlet guide vane) function. The solution, which ispart of the TOMONI Flexible Operation and Performance
Improvement suites, was implemented into RPCL’s existing
control system during a periodic inspection in 2015. Itincreased Turbine Inlet Temperature (TIT) by tuning theIGV function for IGV close. Adding a function to open IGV
temporarily in load change prevented a TIT overshoot inload change.

The IGV Optimization solution in 2015 increased the plant’sefficiency, which reduced fuel consumption, leading to asavings of 30 million Thai baht per year. The efficiency
improved with partial load IGV modulation by about 0.4%
during operation at 80% of full load.

In 2017, the answer was a more sophisticated digital
control strategy that optimized the IGV closure over a wider
load range, both at stable loads and during frequent loadchanges. This new solution was installed during a planned
outage in early 2018, and Mitsubishi Power engineers
tuned and optimized the combustion dynamics, ensuring
any technical challenges of the IGV closing were addressed
before the planned outage was complete.

DATA FOUNDATION& ENABLERS

FLEXIBLE
O&M
OPTIMIZATIONOPERATIONSSOLUTIONSPERFORMANCEIMPROVEMENTIMPROVEMENTSOLUTIONSFLEXIBLEOPERATIONSOPERATIONSSOLUTIONSDATAFOUNDATIONFOUNDATION& ENABLERS& ENABLERS

The 2018 upgrade greatly expanded the load range
where the gas turbine exhaust temperature is optimized
and allowed for frequent load changes to meet market
demands. The additional flexibility puts RPCL in a better
position to increase their profits in today’s market while
responding to future changes in grid dispatch. Mitsubishi
Power and RPCL calculate the improved part load
efficiency enabled by this digital solution will lead to anaverage savings of 45 million Thai baht per year (US$1.2million) on each of the two power blocks.

“This TOMONI digital solution improved our bottom line

by reducing our fuel costs and helping offset the inevitablechanges that take place as a plant ages. Not only did it
make our plant more efficient, but it also helps our facility
fit the realities of our business in a dynamic energy
marketplace without a significant capital investment
for new hardware. Mitsubishi Power technical support
and the overall cost savings we achieved made this aprofitable venture for our power plant.”
O&M
OPTIMIZATIONPERFORMANCEPERFORMANCEIMPROVEMENTIMPROVEMENTSOLUTIONSFLEXIBLEFLEXIBLE
OPERATIONSOPERATIONSSOLUTIONS Charus Thaebanpakul
Chief Operating Officer, RPCLTOMONI® is a suite of intelligent solutions that accelerates decarbonization with power plant design, O&M and system knowledge, together withstrong customer and partner collaborations. TOMONI leverages advanced controls, artificial intelligence and machine learning with multi-layered
cybersecurity to make energy systems smarter, more profitable and ultimately more autonomous on the road to a sustainable future.

O&M
OPTIMIZATION© Mitsubishi Heavy Industries, Ltd. All rights reserved. TOMONI® is a registered trademark of Mitsubishi Heavy Industries, Ltd.
Mitsubishi Power is a power solutions brand of Mitsubishi Heavy Industries.

Data Foundation & Enablers
O&M Optimization
Performance Improvement
Flexible Operations
METP-11DS02E2-A