Mitsubishi Heavy Industries Technical Review Vol. 60 No. 3 (September 2023)
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The Latest Initiative of Intelligent Solution TOMONI®
to Achieve Carbon Neutrality

TORU TANAKA*1YASUYUKI KURODA*2

ITARU ENDO*3

KAZUNORI TSUJII*1

YUYA YOSHIDA*4YUTA KOBAYASHI*4

At present, initiatives toward carbon neutrality are required of every business entity all over
the world. Mitsubishi Heavy Industries, Ltd. (MHI) has formulated initiatives from both aspects of
CO2 emissions reduction and CO2 capture. In order to contribute to achieving our carbon
neutrality goal through the utilization of digital technologies, MHI is developing solution menus
for the intelligent solution TOMONI®, mainly in power generation. This report introduces oursolutions for reducing CO2 emissions from gas turbine combined cycle (GTCC) and steam power(SP) plants and facilities to achieve carbon neutrality.

|1. Introduction
Aiming to solve climate change problems which are global issues, the Paris Agreement was
adopted in 2015 and over 120 countries and regions throughout the world have set a target of “2050carbon neutrality” in order to realize the goals of the Paris Agreement. In October 2020, theJapanese government declared that by 2050 Japan would aim to reduce greenhouse gas emissions
to net zero, that is, to achieve carbon neutrality. MHI has set two growth areas in its medium-termbusiness plan “2021 Business Plan” announced in 2020: “Energy Transition” aiming for
decarbonization on the energy supply side; and “Smart Infrastructure” achieving decarbonization,energy saving and manpower saving on the energy demand side. By promoting the businesses inthese areas and also by promoting decarbonization, electrification and intelligence of existing
businesses, we aim to achieve carbon neutrality by 2040 and contribute toward the achievement ofa carbon-neutral society.
Our intelligent solution TOMONI is a collection of various digitally enabled products andservices and contributes to the promotion of the above-mentioned “Smart Infrastructure”. Morespecifically, some of those products and services lead to the reduction of CO2 emissions directly by
improving the efficiency and operation of power generation facilities through the optimization ofcontrol parameters required for the operation of a power plant or with add-on devices and reducing
the consumption of fuel gas and coals. Others lead to the reduction of CO2 emissions during
manufacture by storing the operation data of a power plant in the cloud and analyzing the data to
optimize parts replacement timing, or to the reduction of CO2 emissions from the movement ofpeople by remotely or automatically conducting maintenance work such as tuning.
This report describes examples of intelligent solutions that are under commercialization,
development and demonstration testing, which contribute to the achievement of carbon neutrality
from the aspect of digital technology utilization.

*1

ICT Operations Department, GTCC Business Division, Energy Systems, Mitsubishi Heavy Industries, Ltd.

*2

Manager, ICT Operations Department, GTCC Business Division, Energy Systems, Mitsubishi Heavy Industries, Ltd.

*3

Chief Staff Engineer, ICT Operations Department, GTCC Business Division, Energy Systems, Mitsubishi Heavy Industries,*4

Engineering Department, Steam Power Maintenance Innovation Business Division, Energy Systems, Mitsubishi Heavy

Ltd.
Industries, Ltd.

Mitsubishi Heavy Industries Technical Review Vol. 60 No. 3 (September 2023)
2|2. What is TOMONI?
As of 2023, we have provided TOMONI services to 138 thermal power plant units
worldwide (as of the end of May 2023), centered on GTCC plants and SP plants, with theconnection to the cloud environment at a high cybersecurity level. TOMONI has provided tocustomers a foundation that supports comprehensive maintenance services for power generation
facilities represented by Long Term Service Agreement (LTSA) and supports availability
guarantees for power generation facilities. In recent years, however, TOMONI has played a role asa communication hub centered on our TOMONI HUB (remote monitoring center) through which
the customer and our company can easily share information on daily problems in power plant
operation to lead to actual measures to solve said problems, contributing to the establishment ofgood relationships with customers. The overview of TOMONI is shown in Figure 1. The
introduction of TOMONI contributes to, for example, “the efficiency and certainty of daily patrol,
inspection and management work in maintenance and the need for the judgment support ofmaintenance workers and manpower reduction” and the “increase of added values of our products
in operation and achievement of specific customer’s benefits such as economic values and carbon
neutrality”. The representative examples of applications that are being put in practical use aresummarized from the standpoint of “contribution to the reduction of CO2 emissions” in Table 1. In
Chapters 3 and 4, the individual applications are introduced.

Figure 1

Overview of TOMONITable 1 Contribution to reduction of CO2 emissions and examples of applications
Category

Examples of applications(* introduced in the report.)- Performance optimization package*((1) IGV Optimization, (2) GT Cooling Air AI-Optimization,
Contribution to the direct reduction of(3) TCA Optimization, (4) Full Load Performance Optimization)
1 CO2 emissions- Boiler optimization solutions*(Plant control optimization)((1) Boiler AI combustion tuning, (2) Netmation OscAR)- Plant operation viewer- Inlet Air Filter Differential Pressure Monitoring*Contribution to the indirect reduction of- GTCC Performance Diagnosis
CO2 emissions
2 (Proper maintenance, quick recovery from - Predictive anomaly detection (Pre-ACT)- Initial response support (Post-ACT)
an unplanned outage, reduction of TA- Trip Prevention Package
dispatch, etc.)- GTCC remote combustion tuning/automatic combustion tuningMitsubishi Heavy Industries Technical Review Vol. 60 No. 3 (September 2023)
3|3. Solutions to achieve carbon neutrality
This chapter describes examples of solutions for individual facilities such as GTCC plants
and SP plants and those for a group of facilities including these plants, respectively.

3.1

Solutions for GTCC plants

Even under the circumstances where renewable energy is positively introduced, thermal
power generation still plays an important role in adjusting the balance between demand and supply,and especially, the presence of GTCC plants that are high-efficient power generation facilities isincreasing. As case examples of solutions to further increase the added value of these GTCC plants,
the “GTCC performance optimization package” that optimizes the efficiency through optimizationof control parameters, the “remote combustion tuning and automatic combustion tuning” that
reduces manpower and the “Inlet Air Filter Differential Pressure Monitoring” that leads to effective
utilization of resources are described.

3.1.1 GTCC performance optimization package
At our GTCC power generation plants, we have strived to maximize the thermal efficiency at
100% load, automate the startup and shut down of units and improve the load following capability
while observing the environmental regulation values. Recently, for plants where the operation rateis decreasing and partial load operations are increasing due to the introduction of renewable energy,
we developed solution menus for optimizing the performance within limit values even in partial
load region by optimizing the opening of the compressor inlet guide vane (IGV) and the operationof the cooling system. The developed solutions with TOMONI are (1) “IGV Optimization”, (2)“GT Cooling Air AI-Optimization” and (3) “Turbine Cooling Air Optimization” (1), and have beendelivered to GTCC power generation plants in Japan and overseas. On the other hand, even if theoperating point is at nearly 100% load, it may deviate from the exhaust gas temperature controlled
operating point due to aging of the gas turbine (GT) and changes in external conditions such ascondenser vacuum. Therefore, we developed another solution: (4) “GTCC Full Load Performance
Optimization” that allows us to additionally control the IGV while observing the actual equipment
status and implemented it in commercial plants after the validation with actual equipment.
It is necessary that these individual performance optimization solutions should be linked andwork with one another and the performance and generator output at every load should be
autonomously optimized in accordance with the operation needs of each power generation plant.
However, the function of optimizing the performance at each load has not been linked so far. We
are now developing a solution package including this function, aiming to provide it to customers sothat they can not only conduct optimal control but also utilize the operating time and effects of thefunction displayed on the Web application as indicators for optimal operation of GTCC power
generation plants.
Moving forward, we will provide it as a GTCC performance optimization package widely tocustomers and contribute to the reduction of CO2 emissions by providing technologies that support
GTCC plants more precisely and timely since the positioning and operation of GTCC plants are
subject to change due to effects of the increase of renewable energy, etc.

3.1.2 GTCC remote combustion tuning/automatic combustion tuning
Stable combustion is very important in improving the availability of GT and GTCC power
generation facilities, and therefore combustion tuning is conducted so that a proper input ratio offuel and air (fuel-air ratio) can be obtained based on the fuel composition and atmosphericconditions. The parameters required for combustion tuning are determined by the combination withmultiple systems in the power generation plant and combustion tuning is very complicated.
Therefore, the expertise of our operation advisors and combustion tuning engineers is required.
Conventionally, they had to go to the power plant to conduct combustion tuning in the site when asignificant change in fuel properties and atmospheric conditions occurred and re-tuning wasneeded. Therefore, the operation could not be conducted or was restricted until our tuning engineer
arrived at the site.
It is technically possible to configure the system that our combustion tuning engineer lets
access the power generation plant over the network and to remotely change the parameters (remote
combustion tuning system). However, the rotating equipment requires high-speed responsivenessMitsubishi Heavy Industries Technical Review Vol. 60 No. 3 (September 2023)
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every second and must be tuned within an operationally allowable delay time attributable tocommunication. As such, we also developed an “automatic combustion tuning system” that allows
the simplification or automatization of the operation that has been conducted by our combustion
tuning engineer using their expertise, and we are working toward the application to actual
equipment (Figure 2). The automatic combustion tuning system allows the customer to check andjudge on changing of parameters in the system, without waiting for our tuning engineer to arrive,
while our combustion tuning engineers and related remotely can support as needed.
These systems will reduce the energy loss generated during the movement of the tuning
engineer and become a means of solving the constraints of movement as experienced under thenovel coronavirus pandemic. The validation of the systems for F-type GT units was conducted withcertain commercial power plant and the technical development was completed. At present, thetechnical development for J/JAC/GAC-type GT units is being conducted.

Figure 2

Automatic combustion tuning

3.1.3 Inlet air Filter Differential Pressure Monitoring
One of the factors of the reduction of GT performance is an increase in pressure drop due tocontamination or clogging with time of the inlet air filter installed at the compressor inlet. At
conventional GTCC plants, generally, the inlet air filter was replaced with a new one according to
the Time Based Maintenance (TBM) to reduce pressure drop and maintain high-efficiency
operation.
Now it has been confirmed that by storing the data on the inlet air filter differential pressure
as a big data in the cloud environment and preprocessing or adding some user interface adjustment,
users can be provided with materials for making judgment on the economic performance and as aresult, more appropriate timing for replacement of inlet air filters can be estimated compared to the
TBM. In other words, when the system has a function of displaying the comparison data between
the past differential pressure trend data and the present data, and the influence quantity data of
output and efficiency reduction as a manufacturer knowing the characteristics of GT, it will allow
us to judge the optimal timing for replacement of intake air filters (Condition Based Maintenance(CBM)) based on cost-effectiveness.
Furthermore, it makes it possible to detect signs of anomaly in a short time and support theoperator's judgment on maintenance. For example, when a cold wave comes, the inlet air filter
differential pressure may suddenly increase due to freezing or adhesion of snow. In the Inlet Air
Filter Differential Pressure Monitoring, when a sign of such a differential pressure rise is detected,
an alert is issued. Then, the operator conducts a site investigation and promptly operates theanti-icing system. The anti-icing operation contributes to the safe operation, but after the anti-icing

Mitsubishi Heavy Industries Technical Review Vol. 60 No. 3 (September 2023)
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operation is started, some of the compressed air that had been supplied to the combustor is supplied
to the anti-icing system and the plant performance will be lowered. Hereafter, the anti-icing
operation will be operated only when needed according to the alert of this application so that thefuel consumption can be reduced (Figure 3).

Figure 3

3.2

Monitoring screen of Inlet Air Filter Differential Pressure Monitoring and use case

Solutions for SP plants - Boiler optimization solutions -One of the efforts toward carbon neutrality is the decarbonization of coal-fired boilers
through fuel conversion into ammonia. Until the technology is implemented, there is a need fortechnologies that contribute to the stabilization of the entire power system while reducing CO2
emissions through efficiency and controllability improvement. MHI is developing solutions for SP
plants, aiming to provide widely applicable intelligent solutions for improving the efficiency andeconomic performance and stabilizing the operation of SP regardless of domestic power plant,
private power plant or IPP.
Static heat balance, combustion properties and dynamic load responsiveness of boiler change
due to fuel properties, aging deterioration, etc. Therefore, it is desirable to conduct combustion
tuning in order to maintain an optimal operation state. In this section, Boiler AI Combustion
Tuning for improving the static characteristics and the boiler control optimization system(Netmation OscAR®) for improving the dynamic characteristics are introduced.

3.2.1 Boiler AI combustion tuning system
There are diverse processes and combinations of control parameters that affect the
combustion state of boilers, and combustion tuning has long relied on the experiences and expertiseof manufacturers' skilled engineers. By replacing them with AI and using a digital twin (a model indigital space representing the same behavior as that of a real machine), we developed a system tosupport the combustion tuning for boilers (Figure 4). We confirmed that the system could
comprehensively improve boiler efficiency, environmental performance, auxiliary power, etc., andachieve improvement of the economic efficiency and reduction of CO2 emissions.
We construct a digital twin that simulates the relationship between changes in boiler
operating conditions and changes in control parameters by using the boiler measurement data andconduct simulations depending on the operating conditions at the time. Thus, it becomes possible toprovide optimal control parameters. Furthermore, we set the constraint conditions of the target realequipment based on expertise in design and control that we have accumulated as a boiler
manufacturer, thereby proposing a practical operation-end setting, and by reflecting it in realequipment at a proper rate, we can improve the economic efficiency while maintaining stable
operation. In May 2023, we delivered this system for a domestic commercial boiler which is inMitsubishi Heavy Industries Technical Review Vol. 60 No. 3 (September 2023)
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commercial operation. In addition, we have had inquiries about several other projects and are in
negotiations.

Figure 4 Overview of boiler AI combustion tuning system

3.2.2 Netmation OscAR (Optimized Suitable Control with AI Robust technology)
With our plant control technologies cultivated over many years, we have achieved stable
operation of boilers for SP at partial load and 100% load with dynamic main process values such as
fuel, air and temperature according to various customer needs. On the other hand, there is plenty
room for improvement of fluctuations of main steam temperature, pressure, etc., caused by changes
in fuel properties due to conversion from coal single-fuel firing to biomass co-firing, etc., to reduce
CO2 emissions, aging, disturbances due to blowing of a Soot Blower (SB), etc. We have studied
approaches other than the conventional control algorithm and conducted system development.
Netmation OscAR is a system that can greatly contribute to fuel cost reduction and stable operation
through “advanced control using AI” and “improvement of control combined with improvement ofan existing control loop” that embodied the expertise that MHI has cultivated as a plant
manufacturer, which no other ICT manufacturers could realize. Specifically, we delivered thesystem for domestic industry and cooperative thermal power boilers, and confirmed the effects
shown in Figure 5.

Figure 5

Example of introduction of Netmation OscAR system

The system has the control improvement functions, “PID Online Optimization Function” and“Disturbance Suppression Advance Control” and provides improvement of control for optimal
operation. In addition, it can be easily introduced because it has a simple system configuration with
only an external PC to be added and connects with customer's DCS for communication of signals.
(Figure 6)

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Figure 6

3.3

Overview of Netmation OscAR system

Energy management solutions

To develop power generation technologies using hydrogen as fuel for fuel conversion which
is important for the decarbonization in thermal power generation, we are constructing the“Takasago Hydrogen Park” at our Takasago Machinery Works where technologies from hydrogenproduction, hydrogen storage to power generation can be verified in an integrated manner.
The Takasago Hydrogen Park is equipped with power generation facilities using hydrogen(large-size GTCC and medium-size GT) and hydrogen production facilities (water electrolyzer,
methane pyrolysis facility, Solid Oxide Electrolysis Cell (SOEC)), which need to be operated while
keeping a balance with the electric power demand of Takasago Machinery Works. Based on thewealth of expertise in operation of energy equipment that we have accumulated as a comprehensive
plant manufacturer, we have been developing an Energy Management System (EMS) by combining
these facilities (Figure 7). For power generation facilities, the EMS utilizes our original AI-based
demand forecasting engine (ENERGY CLOUD®) to forecast factory electricity demand and devise
a power generation plan that enables transmission of electric power. For hydrogen production
facilities, the EMS enables operation planning for optimal hydrogen production with power
generation status and power demand status taken into account by the system linkage. Furthermore,when the Battery Energy Storage System (BESS) is combined with the EMS, the EMS controls thedischarge and charge of the storage battery, and thus a stable and efficient energy supply is realized(Figure 7). We will continue the development of the EMS function of “smartly connecting andcontrolling” these facilities and conduct a long-term validation while using it in our facilities andthen aim to provide the EMS to other commercial power generation facilities as an energy
management solution. The development of such solutions has been conducted based on the conceptof ΣSynX(6).

Figure 7 Energy Management System

Mitsubishi Heavy Industries Technical Review Vol. 60 No. 3 (September 2023)
8|4. Conclusion
In this report, we presented some case examples of our intelligent solution TOMONI that
contribute to the achievement of a carbon-neutral society. They contribute to the reduction of fuelconsumption, improvement of the efficiency of physical and human resources and reduction of CO2
emissions for GTCC plants and SP plants. The MHI Group is also working to improve theefficiency of power generation facilities and promote the use of hydrogen and ammonia toward thedecarbonization of thermal power generation. As described above, the use of the intelligent solution
TOMONI allows us as a facility manufacturer to provide the processing and analysis of operation
data, improve the efficiency of facilities and effectively utilize human and material resources in an
integrated manner. In addition, we aim to not only optimize individual facilities but also construct
an energy management system that “smartly connects” a group of facilities based on the concept of
ΣSynX as described above. TOMONI allows the sharing of digital technologies throughout thewhole MHI Group and the creation of synergy through combination with other various solution
menus and contributes to the achievement of carbon neutrality.
TOMONI® is a registered trademark of Mitsubishi Heavy Industries, Ltd. in Japan and other countries.
Netmation OscAR® is a registered trademark of Mitsubishi Heavy Industries, Ltd. in Japan.
ENERGY CLOUD® and related marks and logos are registered trademarks of Mitsubishi Heavy Industries,
Ltd. in Japan and other countries.

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