Mitsubishi Heavy Industries Technical Review Vol. 59 No. 4 (December 2022)
1

Technology Development of Energy Management System
Beneficial for Carbon Neutral Era

YUSUKE ISOBE*1

MASAYUKI MORIHARA*2

MASAYUKI HASHIMOTO*3 TAKEHIRO NAKA*3

MASATO MITSUHASHI*3 YU KOBAYASHI*4

In order to achieve carbon neutrality, the environment surrounding energy demand andsupply management in the industrial field has been changing dramatically. Mitsubishi Heavy
Industries, Ltd. (MHI) has developed an energy management technology that could serve as ameans to achieve carbon neutrality, and has constructed a system that places the cost incurred
during the life cycle of each piece of equipment at the center of control from the unique perspectiveof an equipment manufacturer. We installed a photovoltaic power generation system and a batteryenergy storage system, which are decarbonized power sources, in our plant, and are currently
validating the functions required for on-site power generation and off-site power generation for
self-consignment. We will continue to enhance functions including the control of cooling andheating equipment while validating the technology we have developed, thus providing
carbon-neutral solutions to our customers.

|1. Introduction
In October 2020, the Japanese government set a goal of achieving a decarbonized society andvirtually zero greenhouse gas emissions by 2050, and MHI Group has declared the goal of carbon
neutrality by 2040. In the industrial field as well, carbon neutrality or decarbonization is an urgent
long-term strategic theme, and we aim to contribute to the achievement of carbon neutrality
through the early establishment of decarbonization technologies and the social implementation ofthese technologies, and products and services based on them.
Against this background, many energy consumers in the industrial field require proposals of
actual carbon neutrality measures and of solutions in line with their energy usage conditions. In
particular, there are many cases of introducing decarbonized power sources such as photovoltaic
power generation equipment for the purpose of self-consumption as a "real solution" to carbon
neutrality. However, photovoltaic power generation and other variable power sources are subject tochanges in their power generation depending on weather conditions, and the amount of electricity
they generate needs to be suppressed to meet the demand characteristics in some cases. Thus, it isdifficult to say that the adoption of such variable power sources is taking full advantage of thebenefits of decarbonizing power sources.
Therefore, we developed a unique-to-equipment manufacturer carbon-neutral energy
management technology that takes into account the component characteristics and life cycle costsof distributed resources such as photovoltaic power generation equipment and battery energy
storage system that absorbs fluctuations. We have actually installed photovoltaic power generation
and battery energy storage system in the Yokohama Hardtech Hub (YHH), a co-creation space inthe Honmoku Plant of MHI Yokohama Dockyard & Machinery Works, to validate the functionality*1

Deputy General Manager, Carbon Neutral Strategy Office, Business Intelligence & Innovation Department, Mitsubishi Heavy*2

General Manager, Carbon Neutral Strategy Office, Business Intelligence & Innovation Department, Mitsubishi Heavy Industries,*3

Research Manager, Power Electronics Research Department, Research & Innovation Center, Mitsubishi Heavy Industries, Ltd.

*4

Chief Staff Researcher, Power Electronics Research Department, Research & Innovation Center, Mitsubishi Heavy Industries, Ltd.

Industries, Ltd.
Ltd.

Mitsubishi Heavy Industries Technical Review Vol. 59 No. 4 (December 2022)
2of this technology. We have also started validation tests using actual equipment to predict thereturn on investment based on the life-cycle costs of the equipment, and to establish the control of
the components and the operation of the equipment based on the monitoring results. We areplanning to confirm the effectiveness of the developed functions through a long-term
demonstration test in fiscal 2022.

|2. Concept of carbon-neutral energy management and value
provided thereby
With an eye toward achieving carbon neutrality, our concept of energy management byenergy consumers in the industrial field, such as factories, and the value provided to customers
created by the use of our energy management technology are as described in the following sections.

2.1

Concept of carbon-neutral energy management

For energy consumers, when their goal is to achieve carbon neutrality in the wide variety ofenergy they use, the suitable management of the equipment for energy supply and demand is one of
the effective ways to achieve the goal, and this is the essence of energy management.
We have defined this energy management for the purpose of carbon neutrality as"carbon-neutral energy management", the concept of which consists of the following threeelements to support the energy consumers' PDCA (Plan-Do-Check-Action) cycle to achieve carbon
neutrality as shown in Figure 1.

Figure 1 Concept of carbon-neutral energy management(1)

Defining the ideal state - Establish appropriate targets
Set the ideal state that is expected to be able to operate efficiently at that point in time,
according to the conditions for both decarbonization and economic efficiency set by theequipment managers and operators.
(2) Making sure – Execute control accurately
Establish an operation plan according to the characteristics of the supply and demandequipment to be controlled so as to achieve the target defined in (1) above, and execute thecontrol according to the plan. This operation plan and control execution reflect our knowledgeof energy equipment as an equipment manufacturer.
(3) Leading to the right path - Support optimal operation
Visualize the discrepancy between the operation plan and control execution described in(2), and present the operator with a means of correcting the discrepancy, taking into account the
impact of the discrepancy on the life cycle cost of the equipment to be controlled.

2.2

Value provided to customers

By utilizing the energy management technology developed this time as a tool for achievingcarbon neutrality, we aim to ultimately provide our customers with the value presented below.
(1) Implementing unique-to-equipment manufacturer features
We have a wide range of products and related technologies that play a central role inenergy supply and demand, including private power generators for electric power supply,
air-cooled chillers for cold/heat supply, and cogeneration systems for combined heat and powerMitsubishi Heavy Industries Technical Review Vol. 59 No. 4 (December 2022)
3(CHP) supply. Utilizing this unique-to-equipment manufacturer knowledge and expertise, theenergy management technology implements control algorithms that reflect the operating
characteristics of the equipment, life cycle costs, and the diversity of the equipment to becontrolled.
(2) Supporting decarbonized power supply equipment
To achieve carbon neutrality, on-site or off-site photovoltaic power generation is anindispensable source of decarbonized power that consumers can manage on their own. In
addition, the combined use with battery energy storage system is also effective from theviewpoint of diversifying means in order to utilize the decarbonized power from photovoltaic
power generation, which is a variable power source, internally without surplus. In developing
the energy management technology, we actually installed the decarbonized power supply
equipment, validated the functional effectiveness, and made the equipment practical.
(3) Managing predicted and resulted effects through simulation
When energy equipment is installed or renewed, it is common to make planning inconsideration of the return on investment, but after the equipment is installed, the operation isoften determined solely on the basis of maintenance and operation costs. Since the operating
environment changes from that at the time of planning, it is desirable to reflect the degree of
influence of environmental changes in the operation plan as needed. Thus, it becomes possible
to improve the accuracy of predicting the return on investment at the time of planning bypredicting the situation ahead from the point of change through simulation with use of thetechnology presented in this report and managing the actual results of costs and decarbonization
effects.
(4) Evaluating with key performance index from life cycle perspective
It is rare for energy equipment to maintain the component performance and equipment
utilization rate set originally at the time of installation planning until the time of abolishment. In
addition, it is easy to imagine that costs, especially maintenance and operation costs, maychange from those at the time of installation planning due to changes in the environment.
Therefore, we have developed a control algorithm based on an index that takes into account thelife cycle, which is represented by the levelized cost of electricity (LCOE), such as changes incomponent characteristics over time and fluctuations in maintenance and operation costs, whichcannot be captured by an index at a certain cross-sectional level. This enables the index to be
updated in real time and realizes the evaluation of the overall optimization in the latest state.

|3. Configuration of energy management technology
As described in chapter 2, operation and energy management after installation of equipment
generally target the reduction of the maintenance and operation costs. However, for achievingcarbon neutrality, it is important to use the decarbonized power equipment fully as planned. Inorder to realize this, LCOE is introduced in this development as an index for operational
determination. In the case of battery energy storage system, an expression levelized cost of storage(LCOS) is generally used, and evaluation in the same system as LCOE can be made by consideringcharging costs, etc.
The flow of energy management using LCOE is as follows.
(1) Making LCOE plan (prior to start of operation)
In the installation of equipment, the LCOE at the time of planning is calculated based on
the expected fuel cost and the amount of electricity generated during the operation period. Thisis defined as the LCOE to be achieved from the life cycle perspective.
(2) Monitoring resulted LCOE (during operation period)
The amount of electricity generated by various types of equipment changes depending on
operating methods, environmental conditions and other factors. Fuel costs, electricity prices,
etc. also change with market trends. The resulted LCOE is calculated by reflecting thesechanges and the difference from the planned LCOE is monitored.
Figure 2 schematically shows the management of predicted and resulted LCOEs and theselection of the operation scenario based on LCOE. The management of predicted and resulted
LCOEs calculates the resulted LCOE of the target equipment from the start of operation to theMitsubishi Heavy Industries Technical Review Vol. 59 No. 4 (December 2022)
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present and predicts the LCOE for each operation scenario based on the past results and future
predictions. The selection of the operation scenario based on LCOE starts the operation in orderof decreasing predicted LCOE in principle, and then evaluates differences in the future LCOEof the target equipment for each operating scenario to select an operating scenario with the
optimal future LCOE.
The operation method of the target photovoltaic power generation equipment can be
categorized as output power limitation, and the operation methods of the target battery energy
storage system can be categorized as peak-shaving operation, Load leveling, surplus power
charging operation, and so on. These operation methods are prepared in advance as operation
scenarios and the selection of an operation scenario is made based on the LCOE.

Figure 2 Schematic diagram of management of predicted and resulted LCOEs andselection of operation scenario based on LCOE

|4. Functions and benefits of energy management technology
Figure 3 shows the summary of the main functions of the energy management technology
developed this time. The outline and benefits of each function are as follows.

Figure 3

Function summary of developed energy management technology

Mitsubishi Heavy Industries Technical Review Vol. 59 No. 4 (December 2022)
5(1)

Function to improve the self-consumption rate of photovoltaic power generation
It monitors the power at the network connection point to maximize the use ofphotovoltaic power generation and limits the output of photovoltaic power generation when
there is a possibility of reverse power flow.
(2) Demand control function according to photovoltaic power generation output
It controls demand equipment (increases/decreases the demand) according to the power
generated by photovoltaic power generation.
(3) Energy management integrating function
It combines the operation of battery energy storage system operation (Load leveling, peakshaving, surplus power charging, etc.) with (1) and (2) to perform integrated energy
management and utilizes the results of photovoltaic power generation and electricity demandpredictions to perform operational control based on criteria such as LCOE and CO2 emissions.
Energy storage equipment also has a function to individually control power converters
according to the charge rate and degradation state with the aim of aligning the degradation state
for multiple groups of battery energy storage system is included.
(4) Self consignment function for off-site power generation equipment
It manages (in the case of demonstration, assumes) the self consignment between twosites by creating planned values of the amount of power transmitted and received for selfconsignment based on predictions of photovoltaic power generation and power demand to
perform 30-minute planned value simultaneous equivalence control so that compliance with theplanned values is ensured.

|5. Validation of basic functions using actual equipment
We validated the basic functions of the energy management technology described in chapter
4 by using the demonstration system installed at YHH. Figure 4 shows the configuration of thedemonstration system. In the cloud-side system (TOMONI®), an operation plan is formulated byutilizing our proprietary AI demand prediction engine (ENERGY CLOUD®) to predict
photovoltaic power generation and power demand in the TOMONI environment. TOMONI is acollective term for a variety of digital energy-related products and services, and here it refers to thesystem infrastructure that supports them.

Figure 4

Demonstration system configuration

The edge systems (energy management system controllers, hereinafter referred to as "EMS
controllers") are installed at two sites: YHH and the hybrid power generation equipment(EBLOX®) demonstration equipment in MHI's Sagamihara Plant. At YHH, we newly installed
photovoltaic power generation equipment, a energy storage system, and an EMS controller. The

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EMS controller controls the equipment according to the operation plan and operation mode
selection policy developed by the cloud. At the Sagamihara Plant, we newly installed only the EMS
controller and built an interface with the local controller of the existing hybrid power generation
demonstration equipment. By connecting the two sites via TOMONI, a function assuming selfconsignment between YHH and the Sagamihara Plant was realized.
As examples of the results of validation of basic functions using the demonstrationequipment, Figure 5 shows an example of the energy management integrating function and
Figure 6 shows an example of the self consignment function. It was confirmed that the energy
management integrating function shown in Figure 5 was able to reduce the amount of electricity
purchased from the power company by utilizing the photovoltaic power generation equipment
while charging and discharging the battery energy storage system, and that the self consignment
function shown in Figure 6 was able to operate the battery energy storage system to compensate forerrors in the planned value of the power received based on the prediction results, which resulted ina similarity between the planned value and the resulted value, albeit for a limited period of time.
After these basic operation tests, we started a long-term demonstration test in June 2022, in
which we will validate and enhance the performance of the energy management technology wehave developed, and to visualize the CO2 emissions reducing effect.

Figure 5

Example validation result of integrating function

Figure 6

Example validation result of self consignment function|6. Conclusion
MHI Group has developed energy management systems that can serve as a tool for achieving
a decarbonized society through the entire value chain, from the unique-to-equipment manufacturer
perspective. The main feature of this technology is to control, operate and manage distributed

Mitsubishi Heavy Industries Technical Review Vol. 59 No. 4 (December 2022)
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resources such as photovoltaic power generation equipment and battery energy storage system,
which are believed to be a realistic solution for decarbonizing power sources, based on the life
cycle costs. We are still working on long-term evaluations and logic enhancement, including theconstruction of prediction simulations.
This report presented energy management mainly for electric power equipment, which is themain focus for carbon neutrality. However, for energy consumers in the industrial field, such as
factories, cold/heat supply equipment is also an important factor in considering carbon neutrality in
Scope 1. As shown in Figure 7, we will expand the functionality of the energy management
technology developed this time by applying it to cold/heat supply equipment and will develop thistechnology as carbon-neutral solution services for customers.

Figure 7

Expansion of energy management functions and contents

TOMONI® is a registered trademark of Mitsubishi Heavy Industries, Ltd. in Japan and other countries.
ENERGY CLOUD® and related marks and logos are registered trademarks of Mitsubishi Heavy
Industries, Ltd. in Japan and other countries.
EBLOX® and COORDY® are registered trademarks of Mitsubishi Heavy Industries Engine &Turbocharger, Ltd. in Japan.

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Kazuyuki Wakasugi et. al, Development of High-precision Demand Forecasting Technology for Factories,
Mitsubishi Heavy Industries Technical Review, Vol.55 No.2 (2018)