R&D Activities ● CO2 Storage Research GroupRITE Today 2023

CO2 Storage Research Group
Member (As of Apr. 2023)
Ziqiu Xue, Group Leader, Chief Researcher
Nobuo Umeda, Deputy Group Leader, Chief Researcher
Satoru Yokoi, Chief Researcher
Makoto Nomura, Chief Researcher
Nobuo Takasu, Associate Chief Researcher
Takahiro Nakajima, Associate Chief Researcher
Takeshi Myoi, Associate Chief Researcher
Tsutomu Hashimoto, Associate Chief Researcher
Saeko Mito, Senior Researcher
Tetsuma Toshioka, Senior Researcher
Osamu Takano, Senior Researcher
Keisuke Uchimoto, Senior Researcher
Hironobu Komaki, Senior Researcher
Atsushi Ibusuki, Senior Researcher
Yuji Watanabe, Senior Researcher
Yi Zhang, Senior Researcher
Hyuck Park, Senior Researcher
Jiro Suekuni, Senior Researcher
Yuji Yamashita, Senior Researcher

Ken Asajima, Senior Researcher
Satoko Fuchikami, Vice Manager
Kimiko Nakanishi, Chief
Takayuki Miyoshi, Researcher
Masafumi Kotani, Researcher
Takeya Nagata, Researcher
Rasha Amer, Researcher
Jinrong Cao, Researcher
Ryota Okimoto, Researcher
Tomonari Minezaki, Researcher
Shoichiro Hozumi, Researcher
Junko Hirai, Research AssistantShiori Tsuji, Research AssistantYuko Himi, Research AssistantAkemi Nishide, Research Assistant
Megumi Okumichi, Research Assistant
Megumi Sasaki, Research Assistant
Tokio Sasai, Research Assistant
Nae Hidaka, Research AssistantTechnology Demonstration, Knowledge Sharing and Non-technicalSupport for Implementation toward Commercial Deployment of
Geological CO2 Storage
1. Introduction

Hokkaido.

“CCS Long-Term Roadmap” which was compiled by

CO2 Storage Research Group is working on the prac-

the government in March 2023 says that CO2 geologi-

tical application of CO2 storage technology on the scale

cal storage-scale as of 2050 is 120-240 million tons.

of 1 million tons per year (a project funded by the New

Aiming to start the CCS business in 2030, they are

Energy and Industrial Technology Development Organ-

speeding up the development of the environment for

ization (NEDO), called “Research and Development ofpractical use of CCS, including the legal system. At the

CO2 Storage Technology to implement safe CCS”).

same time as ensuring the safety of the CCS project,

The main purpose of this project is to develop tech-technology development for cost reduction, etc. is also

nology to improve the safety and economic efficiency

required.

of the CCS project and to prepare the conditions for theTechnology development of CO2 geological storage

wide adoption of CCS. We have developed Distributed

technology in Japan started with a small-scale demon-

Temperature Sensing (DTS), Distributed Strain Sensing

stration project (10,000 tons of CO2 injection) in the(DSS) and Distributed Acoustic Sensing (DAS) measure-

suburbs of Nagaoka City, Niigata Prefecture in the early

ment technologies, and microbubble CO2 injection

2000s, and various basic technologies were developed

technology to improve storage efficiency. Currently, weby the early 2010s. After that, a large-scale CO 2 injec-

are proceeding with technical demonstration project attion demonstration project of a total of 300,000 tons

domestic and overseas sites. We are also working on thewas conducted at the off the coast of Tomakomai,

development of methods to improve the social

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acceptance of CCS technology toward social implemen-(Distributed Strain Sensing: DSS), simultaneously. Thistation.

system can reduce the cost significantly compared with

Regarding optical fiber measurement technology, we

the case which many sensors are installed separately.

are also accumulating know-how such as verification of

Our research group has developed the monitoring

effectiveness and measurement system operation forsystem with the DFOS technology through the labora-

practical application to domestic CCS projects at large-

tory experiments and field measurements. Currently wescale CO2 injection sites in the United States. About thedemonstrate our monitoring systems at various sites inmatching of emission sources and storage sites andJapan and overseas.

about the economic improvement (cost reduction) of

the sensitivities of the newly developed OF cable, anddomestic CCS projects”, we are considering the " Stor-

verify the effectiveness of the DFOS monitoring system

age Resource Management " (SRM) method based onunder the practical environment such as the injection atexisting geological information and underground ex-

multiple wells.

ploration data. In addition to the conventional storage

USA, we demonstrate the integrated monitoring system

potential assessment, we are also developing a CCS costwith DAS, DTS and DSS using the developed OF cables.

estimation tool that enables optimal business planning

The CCS project in ND, USA injects 180,000 tons of

by SRM. In addition, our group has been developing

CO2 annually captured from the ethanol facility into theframeworks for creation of social consensus (Social Li-

deep saline aquifer approximately 2,000 m below

cense to Operate, SLO) which is useful for domestic CCS

ground surface. The CO2 operation was started at mid

projects by advancing conventional Public Acceptanceof June, 2022 and over 100,000 tons of CO2 was stored(PA) and Public Outreach (PO) approaches.

at the end of March, 2023.

At the domestic site, we evaluate

At the CCS site in North Dakota (ND),

Our DFOS system is used for CO2 monitoring in this
2. Major Research Topics and Outcomesproject. Fig. 1 shows the map of the ND CCS site and a

2.1. Optical fiber measurement technology develop-

schematic diagram of the monitoring system with thement and demonstration

DFOS technology. Simultaneous measurement systems

In geological carbon storages, it is required to con-of DAS (acoustic), DTS (temperature) and DSS (strain) is

firm that the injected CO2 is stored subsurface safely.

implemented by installing the developed OF cables at

We need to monitor integrity of wells and CO2 pipelines

four wells (an injection well, an observation well, two

to obtain deformation change due to the increase ofshallow groundwater observation wells) and the CO2

formation pressure, area of pressure propagation andpipeline. Table 1 summarizes the monitoring targets ofleakage detection. The Distributed Fiber Optic Sensing

each measurement system.

(DFOS) technology is highly prospected for this monitoring purpose.
The DFOS measures spatially continuous data along
the optical fiber (OF) cables, as the OF cable itself works
as sensors. A single OF cable with multiple fibers enclosed can be a multi-sensor system to obtain acoustic(Distributed Acoustic Sensing: DAS) temperature (Distributed

Temperature

Sensing:

DTS)

and

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implemented surface orbital vibrators (SOVs), which canacquire data much more frequently. The SOVs are permanent vibration devices that transmit vibrations in thestrata by rotating eccentric weights at high speed. In
addition, there is no need for on-site operators for dataacquisition, as remote operation and automatic controls are available. At the ND site, four SOVs are installedaround the site and operated every day.
Fig. 2 shows DAS results excited by SOVs installed at
the offset of about 60 m and about 1,000 m from theinjection well, respectively. Direct P-waves continuingfrom the upper left to the lower right propagate fromthe surface to the underground (down-going), while
Fig. 1 Monitoring system with O.F. sensing

waves continuing from the upper right to the lower left
represent reflected waves propagating upward from theTable 1 Monitoring targets
DAS (Acoustic)
DTS(Temperature )DSS (Strain)underground (up-going).

Reflected P-waves, which

CO2 plume,are the main signals in VSP data processing, are wellinduced/natural seisimicity

recorded with the good signal-to-noise ratio. The zeroWell/pipeline integrity

offset VSP recordings, which were obtained by the

Geological stability of reservoir/cap
rocksource sweepings at the closest SOVs, are used to detect the CO2 plume immediately after the start of injection, and other VSP recordings with certain offsets are

The borehole seismic with DAS (DAS-VSP) is used atused to capture the area of the CO2 plume. We are cur-two of deep wells to capture a CO2 plume subsurface.

rently conducting time-lapse analysis of repeated VSP

The VSP (Vertical Seismic Profiling) is one of the explo-

recordings.

ration seismic techniques and has advantages for highFig. 3 shows the DTS result at the injection well before

resolution and quality imaging due to the short dis-and after the start of injection. The color contour charttance between the target and receivers compared toclearly shows spatial and temporal temperature

the surface seismic. The OF cable works as the perma-changes. While the temperature distribution along thenent seismic receivers installed behind the well pipe,

well due to the geothermal gradient is consistent before

which reduces the operation time and costs significantly

the start of injection, the temperature drops by about

especially for repeated surveys and also reduces the ac-

20 °C immediately after the start of injection. This rep-

quisition errors due to the gap of the receiver locations.

resents that the low-temperature injected CO2 cools

The OF cable with small dimensions is installable behindsurrounding ground temperature. Moreover, even after

the well pipe even at the injection well.

the start of injection, repeated short-term temperature

Repeated 3D seismic surveys are typically carried out

rises and drops are observed. This indicates the process

every one to several years for the purpose of capturingin which cooled temperature tends to recover to thethe CO2 plume. In order to fill this temporal gap, we

original formation temperature due to the temporary60

R&D Activities CO2 Storage Research Groupsuspension of injection.
Spatially continuous DSS (strain) from the deep un-

RITE Today 2023

well (Brumby 3), an observation well (Brumby 4) andtwo existing wells for the CO2 leakage detection test.

derground to the surface is performed to monitor the

In previous research by CO2CRC, an Australian re-

deformation of the strata caused by the CO2 injection.

search institute, a well was drilled through a shallow

In the ND CCS project, we also monitor ground surface

fault zone and DTS (temperature) was measured using

deformation using the satellite data in order to evaluate

OF cables. As the DTS monitors the temperature

the relation between the ground surface deformation

change at only a small range around the installed ca-

and CO2 injection at the deep strata.

bles, we drilled two new wells with the newly developed OF cables installed for high performance DSS(strain). These OF cables are also available for DTS(temperature) and DAS (acoustic).
A CO2 injection test is scheduled in this summer.
The CO2 will be injected at the injection well (Brumby3) and some of CO2 gas will move toward the groundsurface along the fault zone. We expect that the DFOS
monitoring system at the observation well (Brumby 4)
detects this CO2 migration.

Fig. 2 SOV-DAS records

Fig. 4 Well layout at Otway site

2.2 SRM method development: development of cost estimation toolFig. 3 DTS result before/after start of injection

As the Storage Resource Management (SRM) method
development, we are developing a method for effec-

On the other hand, at the Otway site in southwest-

tively utilizing the underground storage capacity (re-ern Victoria, Australia, a field experiment is underway

source) at the CO2 storage site and a tool for evaluating

for aiming to detect CO2 leakage from shallow faults

the cost of the entire CCS project. The entire CCS projectusing the DFOS monitoring system. Fig. 4 is a cross-includes the stages of CO2 capture, transportation, andsection showing the layout of a newly drilled injection

storage, and we aim to enable cost estimates61

R&D Activities CO2 Storage Research GroupRITE Today 2023

corresponding to various options for CO2 emission

screen, but because they can be easily copied andsources,pasted, they can be imported into Excel or dedicatedtransportation

methods,

andinjectionamounts.

graph creation software, and graphs can be createdfreely. By using the output from this tool, Fig. 6 shows

2.2.1 Features and configuration of the Tool
Our research group is developing the CCS cost estimation tool that allows even non-experts to appropri-

CCS costs by transport volume and by distance in caseof using pipelines and ships. It should be noted that thepipeline here is assumed to be an onshore type.

ately estimate the cost of CCS, and that experts can also
use for various CCS case studies. As for the specifications of the tool, in addition to trial calculations for individual cases, it is equipped with a mechanism that cancollectively process multiple cases. And in addition tocomparison studies for each case, studies that combine
cases are also possible. The features of the tool underdevelopment are described below.
1) User friendly interface: The input interface has
been devised so that the user can enter the necessary
data appropriately without hesitation while looking at
the screen, and can give instructions to execute calculations. If the screen is difficult to understand or the operation is complicated, the user cannot input specifications correctly, which leads to incorrect results or wastes
operation time. Therefore, a easy and clear input interface is important. Fig. 5 shows the case selection screen.
From this screen, it is possible to call up the specification confirmation screen and execute calculations.

Fig. 6 CCS costs by transport volume and distance forpipelines and ships2) Installation of DBMS (database management system): A general-purpose DBMS was installed for the
purpose of easily and safely managing data in eachstudy case for each user. It is also important to install
the DBMS in order to make the interface, data management part and calculation engine independent. Completion of the cost estimation tool does not mean thatthe entire series of development ends. And continuous
maintenance, such as rule changes, rule additions anddata updates are required. This tool aims to improve
maintainability by increasing the independence of eachpart.
3) Developed as a WEB system: No special operationsof software or update are required on the user side, andit can be used only with a browser. Also, because all calculations are processed on the server, they are not af-

Fig. 5 Case selection screen

In addition, the output interface is also important.
Calculation results are output as a table on the web

fected by the capabilities of the user's PC or platform.
Therefore, it is possible to use smartphones and pads inthe meeting room to change specific specifications andto recalculate.

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2.2.2 Development progress and future development

2.3. Methodology for the Creation of Social Consensus

plans(Social License to Operate, SLO)

Fig. 7 shows the modules that have been installed so

The social consensus, including the local community,

far (red frames) and the modules that are planned to beis essential to implement CCS projects. One of the key

developed (blue frames).

issues in the creation of social consensus (Social License
to Operate, SLO) methodology is how business developers should communicate with residents so that they
understand the need for CCS and support the project.
From the perspective of communication between
business developers and residents, CCS business’s significant character is the extremely low awareness of CCS
among the general public. In a recent awareness survey,
14% of the respondents said they knew about CCS, andFig. 7 Modules installed so far and modules to be developed

For capture, coal-fired power plants and LNG-fired
power plants have already been installed. For transportation, it is possible to calculate “the pattern of land
pipeline” and “the pattern of which, as one of ship transportation, loading from land and transporting it overthe sea and then unloading it on land again”. In the caseof storage, it is possible to calculate the pattern of injecting water from the land into the sub-sea level witha sloping well. From now on, we plan to gradually develop the modules shown on the right side of the figure.
In the coming modules, in addition to the cost calculation of each process, we plan to add calculation functions that extend the basic functions such as sensitivity
analysis and hub & cluster.
In the first stage of development (until the end of
FY2023), we plan to specialize in the trial calculation of
the costs required for CCS. But in the future, we plan todevelop them so that we can also use them for considering business models, by installing functions to calculate economic indicators that take incentives into account, etc.

42% said they had heard the word CCS. It was a situation that almost half of them had never even heard theword CCS. For this reason, the primary purpose of initialcommunication for CCS projects is to raise awareness of
CCS, that is, to make residents get to know CCS.
The Barendrecht project in the Netherlands is a notable CCS project that was canceled due to opposition
from residents. It has been pointed out that the reasons
for residents' opposition were the lack of a lots of important aspects of risk communication, such as the fairness of procedures and trust. However, what is noteworthy here is that it is believed that the residents did
not fully understand the CCS (project). Initially, residents
were not considered as stakeholders and were not adequately informed. In addition, after the residents' opposition became apparent, providing of informationfrom public was regarded by the residents as ``propaganda of the CCS supporters,'' and the providing of information to the residents did not function enough.
Since the residents did not obtain sufficient information,
it is possible that their opposition was not based on
their understanding of CCS or the project. In otherwords, there is a possibility that the opposition was
based on information heard from reliable people (celebrities, media, etc.) or many people. In such cases,

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decisions may be made based on wrong information. In

with low interest in science and technology increases if

fact, in Barendrecht 's case, the cover of a magazine is

the theme is related to their personal interests or di-illustrated as a picture of a volcanic eruption spewing

rectly related to their lives. From this point, it is consid-

CO2 out into the city, something that cannot happen.

ered necessary to hold two types of communication

One of the importance of raising awareness of CCS in

events in the early stages of CCS projects: events fo-

the early stages of the project is to increase the number

cused on science and technology, and events focusedof people who understand CCS and the CCS project andon matters directly related to people's lives.

can decide whether to approve or disapprove of the
project.

Also, from the viewpoint of easiness for participation,
it is effective to hold the event online. Due to the corona

Literature on communication points out that it is im-

crisis, some of the events that had been held face-to-portant for business developers to listen to the opinions

face until then were now held online, but there is a re-of residents/citizens and engage in dialogue (two-way

port that, thanks to the online event, people who had

communication) rather than giving one-sided explana-less participation in face-to-face events are now partic-

tions (one-way communication). However, this is not

ipating. However, while it is easy to participate in online

necessarily the case for communications in the early

events, it also has the disadvantage that it is easy to notstages of a CCS project. Even if opportunities for dia-concentrate on watching or to stop watching in thelogue are created, there is a risk that many people will

middle.

not positively participate. It has also been pointed out

What has been described so far is only about com-that many people are unwilling to spend their precious

munication at the beginning of the project. And the im-time and effort to cooperate in solving social issues.

portance of two-way communication increases as the

Others may prefer passive (one-way) communication. In

project plan becomes concrete. It is necessary for thecase of two-way communication, they feel that theybusiness developer to have two-way communicationmust express their opinions, and feel a heavy mental

with the residents and reflect the results in decision-burden. For this reason, it is considered important thatmaking, instead of explaining the decisions made by thethe burden of participation is small and that it is easy tobusiness developer to the residents and making them

participate, rather than whether one-way or two-way

accept it. This becomes important for the smooth im-communication, in the early stages of a project.

plementation of the project. In addition, in parallel with

Lectures, exhibitions, and science cafes are held assuch events, public relations activities using the web,scientific events to spread science and technology, es-SNS, pamphlets, etc. are also necessary from the initialpecially to make people who have little interest in sci-stage of the project in order to raise awareness of CCS

ence and technology more familiar with science andand the CCS project.

technology. These scientific events are also suitable for

Our research group is also creating a QA collection

early-stage communication events of CCS projects duethat can be referred to when explaining CCS to residents

to their low participation burden. However, many sci-and answering questions from residents. It is said thatence events are known to have a very low participation

the main fears and concerns that the general public

rate of people who have little interest in science andfeels about CCS are CO2 leakage and triggering oftechnology, on the contrary to their purpose. However,

earthquake. Therefore, the QA collection particularly fo-

even in science events, the participation rate of people

cuses on these two themes. A (Answer) is based on

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R&D Activities CO2 Storage Research GroupRITE Today 2023

scientific knowledge including the research and devel-

generation handbooks and greenhouse gas emissions

opment results of our research group so far, but we try

calculation, reporting, and publication system, andto make the explanation understandable even without

sorted out as direct emissions. The emission source da-prior knowledge.

tabase contains location information and it can be

In order to reach agreement by residents and citizens,shown on maps. Even if the amounts of emissions from

it is important that they come to understand CCS tech-individual companies is small, grouping emission

nology itself, and it is also important that they come tosources as a regional cluster will be useful in consider-know the benefits of conducting CCS projects. In caseing a hub-and-cluster approach to CCS. By integratingof overseas CCS projects, they introduce the amount of

the emission source map and the potential capacity

investment and the increase in the number of employ-map of CO2 storage sites owned by RITE, we devised

ees which are brought by the implementation of theways to make it easier to visualize the business image.

project. In case of facilities of about 1 million tons/year,

Furthermore, by adding port information, it has become

which they regard as a commercial scale, it is reported

possible to plan transportation routes from emissionthat capital investment’s amount of approximately 100

sources to reservoirs, including not only land routs but

billion yen is expected. It is also reported that the em-

also sea routes. Currently, we are also developing theployment effect is several thousand during construction

CCS cost estimation tool, and are compiling the SLO

and several dozen during operation. In the Unitedmethod so that we can examine the merits of imple-

States, it has also been shown that implementing CCS

menting CCS from an economic point of view as well.

without decommissioning coal-fired power plants is effective in preventing unemployment and the decline of
local industries. In this area, there is a coal mine adjacent to the coal-fired power plant. Since most residents
are involved in power plants and the coal industry, theclosure of coal-fired power plants will have a negative
impact not only on residents, but also on the survival ofmunicipalities. In Japan as well, there are concerns thatthe tax revenues of local governments will decrease
dramatically due to the closure of oil refineries, ironworks, coal-fired power plants, etc., which are sourcesof large amounts of CO 2 emissions. CCS, as a decarbonization option, can contribute to sustainable regional operations, with substantial local benefits.
For the commercialization of CCS, it is necessary toenvision a CCS business model that suits the situationin each region of Japan. We developed an emission
source database to grasp CO2 emissions. CO 2 emissions
were converted from summary results of greenhousegas emissions which are based on thermal power65