Sustainability Site Terminology


Ballast water

Because a ship is more prone to capsize when it carries less cargo, water is pumped into an unloaded cargo ship to provide stability. This water, serving as a counterweight, is called ballast. Water used as ballast is called ballast water, which is usually taken from coastal port areas. It is concerned that the contained organisms in the ballast water could be non-native species and thus may harm the ecological system of the seawater in the next port of call area when it is discharged.


Biogas is a combustible gas derived by methane fermentation of anaerobic microorganisms in organic waste such as raw garbage, livestock manure and sewage sludge. The principal components of biogas are methane and carbon dioxide. It is an unused renewable energy source, of which efficient use is expected to contribute to the mitigation of global warming.

Blue & Green Project

The project is sponsored by Better Living and co-sponsored by the Japan Gas Energy Promotion Council.

Boiler operating efficiency

Overall boiler efficiency after long-term use, which takes into account load changes when the boiler is switched on or off.

Business continuity plan (BCP)

It refers to plans and management strategies to ensure that important business operations are not interrupted even in the event of a disaster, and that important functions are resumed within the target recovery time even if business activities are interrupted.


Carbon offset

The concept is to offset greenhouse gas (GHG) emissions such as CO2 emitted from homes and businesses by investing in GHG reduction activities such as afforestation, forest protection, and clean energy projects. Products that include a donation to CO2 reduction activities in the price of the product are called carbon offset products, and purchasing such products indirectly offsets carbon emissions.

Clean Development Mechanism (CDM)

The Clean Development Mechanism is a mechanism that allows a developed country to apply a certain amount of its GHG emissions reductions to the GHG reductions of a developed country when the developed country reduces its GHG emissions by providing technical and financial assistance to the developing country.

Cleaning up the site

A method that conducts on-site purification without excavating contaminated soil.

CO2 Emissions from Energy Consumption

CO2 generated and emitted associated with the burning and use of fuel.

Compressed Natural Gas (CNG)

CNG is usually stored in a pressure-resistant container for transportation and storage.


A type of ultra-light crude oil that exhibits similar characteristics to naphtha and gasoline.

Cryogenic power generation

Osaka Gas imports LNG, that is natural gas liquefied in producing countries. This LNG is a liquid with a temperature of minus 160 degrees Celsius, and when it vaporizes back into natural gas it absorbs heat from the surroundings giving it cooling properties (cryogenic energy). This energy is equivalent to about 240 kWh of electricity per ton of LNG. Recovering this as kinetic energy and using it for power generation is referred to as cryogenic power generation.


Demand response

Demand response represents efforts by the demand side or electricity users to strike a supply-demand balance of electricity by saving their power consumption.

Digester gas

Digester gas is made by anaerobic fermentation in sewage sludge where no oxygen exists. It is mainly composed of methane and CO2.


A structure set up around an LNG tank to prevent the spread of LNG in the vicinity of the tank in the event of a leak.

Double Power Generation

Double power generation is an electricity-generation system combining gas cogeneration and solar power-based electricity generation.


Excavated soil

The earth, sand, and asphalt that are dug up when gas pipes are constructed under roads or when gas pipes are moved.


FIT electricity

FIT stands for feed-in-tariff. FIT is a mechanism designed to spread the use of renewable energy sources such as solar power and wind power by obliging utility companies to purchase such energy sources from renewable energy producers at fixed rates set by the state for a certain period. FIT electricity is electricity generated using renewable energy sources purchased under this mechanism.


Gas cogeneration system

An energy-efficient system that runs on city gas, generating the power and heat where they are used such as homes and businesses, and using the waste heat from the system to heat or cool the air, or to heat water. Electricity is generated by kinetic energy from gas engines and gas turbines, and by fuel cells, which are powered by a chemical reaction between hydrogen and oxygen. Two types of energy, electricity and heat, are generated from these systems fueled by a single energy source.

Gas pipeline service business

Business of supplying gas using specified pipelines of which maintenance and operation are consigned by the company.

Gas pipes

The pipes that make up the pipeline for the delivery of gas to customers. There are three types of gas pipes depending on the pressure of the gas running through them: high-, medium-, and low-pressure gas pipes. The gas that leaves LNG terminals flow through a high-pressure pipeline. A pressure regulator adjusts the pressure to medium- and low-pressure levels before the gas is delivered to our customers through a low-pressure pipeline.

Gas turbine combined cycle power generation method

A high-efficiency power generation method in which gas turbines and steam turbines are combined. City gas, mixed with compressed air, is combusted in the burner, and the pressure generated by the combustion drives a turbine to generate electricity. Next, the heat of the exhaust gas from the turbine is used to generate high-pressure steam in a waste-heat collecting boiler, and this steam drives a steam turbine to generate electricity. This use of heat from the exhaust gas gives the gas turbine combined cycle method a high power generating efficiency.

Gene farm

A facility that has the role of protecting and preserving genetic resources, as well as increasing the number of individuals and restoring native populations. It mainly targets wild plants that are threatened with extinction and those that have been rapidly declining in number recently.

GHG Protocol

Abbreviation for The Greenhouse Gas Protocol. It is a set of guidelines developed by the World Business Council for Sustainable Development (WBCSD) and the World Resources Institute (WRI) that sets forth the concepts and rules for calculating corporate GHG emissions and reductions.

GRI Standard

The Global Reporting Initiative (GRI), an international NGO, created the Sustainability Reporting Standard to promote policy formulation, planning, and specific initiatives by businesses to enable the sustainable development of society. Since the first edition of the Guidelines was published in 2000, the Guidelines have undergone a series of revisions, and in 2016 the format was shifted from a guideline format to a standard format. As a common standard, "General Disclosure Items" and "Management Approach" are required to be disclosed, and as an item-specific standard, items identified as material among "Economic," "Environmental," and "Social" items are required to be disclosed. The official name is GRI Sustainability Reporting Standards, and the publication date is July 1, 2018.


Home energy management system (HEMS)

HEMS contributes to residents' energy saving with features such as visualization of energy consumption, giving energy advice to residents and automatic control of various housing services.

Hydrogen filling station

A facility that provides hydrogen to vehicles running on fuel cells. Hydrogen is a super-clean energy since it emits no CO2, a greenhouse gas, during combustion.


Independent power producer (IPP)

IPP is a private entity that generates electricity and sells to power companies. Under revisions to Japan's Electricity Utilities Industry Act in 1995, IPPs can take part in competitive bidding with power companies.


It is an international environmental management system (EMS) standard created by the International Organization for Standardization (ISO). The basic structure of the EMS is the PDCA cycle, which is a process of (1) planning, (2) implementation, (3) inspection and correction, and (4) review, in order to continuously improve the level of environmental management.


It is an international standard on social responsibility published by the International Organization for Standardization (ISO) in November 2010. It is a guidance document on universal social responsibilities such as environmental protection and respect for human rights toward the creation of a sustainable, just, and equitable society. Using a multi-stakeholder approach, more than 600 participants from various sectors in 99 countries and 42 organizations took part in its formulation.


J-Credit system

CO2 emission reductions achieved by small and medium-sized companies through the introduction of high-efficiency equipment are converted into credits and are purchased by large companies. The scheme, called the J-Credit system, is designed to cut CO2 emissions in Japan.


Linaria japonica (Unran)

This perennial herb belonging to the sesamoidea family grows in sandy areas along the coast and produces yellowish-white flowers from August to October. In recent years, the number of places where it grows has been decreasing due to the progress of coastal reclamation, and it has been designated as an endangered species, rank A by Hyogo Prefecture.


Liquefied Natural Gas. Liquefied natural gas is made by cooling methane (CH4), the main component of natural gas, to minus 160°C and liquefying it, resulting in a volume approximately 1/600th that of gas. Liquefied natural gas is liquefied in the Middle East, Indonesia, and other regions, and then transported to the place of consumption by dedicated tankers.

Lower heating value (LHV)

LHV is the amount of heat released when the fuel undergoes full combustion, which excludes the latent heat of condensation of water vapor generated (heating value used to transform vapor into water).


Micro-cogeneration system

Gas cogeneration system of up to 100 kW of generation capacity.


Native seedlings

Native seedlings are those that have been grown from locally gathered seeds. One of the important points is that their production process is clarified.

Natural gas vehicle (NGV)

NGV is a vehicle equipped with a natural gas-powered engine.


Occupational Safety and Health Management System (OSHMS)

Occupational Safety and Health Management System. It refers to a system for proactively promoting safety and health management in a planned and continuous manner with the aim of improving the level of safety and health at workplaces.

Once-through boiler

In a once-through boiler water is supplied to a pipe and steam is produced from the other end. The boiler can produce steam quickly because it is compact and not much water remains in the pipe of the boiler.
Once-through boilers are categorized into three types, which are regular boilers, small-sized boilers and compact boilers, according to the maximum pressure used and the width of the heat transfer area. Compact once-through boilers are the smallest of the three types. They require no operating license.

On-site containment

A method for containing soil on-site that does not meet the environmental criteria by means of diaphragm (water-blocking) walls or other devices.


Peak demand cut

Responding to power shortages, changing the settings for home appliances and avoiding the use of electricity during peak times can contribute to energy savings and reduction in peak demand.


A system of continuous fixed, above-ground or below-ground pipes that transport gas to its destination. An efficient network of gas pipelines, consisting of a high pressure trunk pipeline and medium and low pressure gas lines, which has been developed in line with our long-term supply plans developed to meet the growing demand for gas.

Polyethylene (PE) pipes

Polyethylene (PE) pipes used for underground installation. They are flexible and highly resistant to earthquakes. PE pipes were confirmed quake-resistant because they were not damaged by the Great Hanshin Earthquake. PE pipes also have an excellent corrosion-resistance for underground use.

Polymer electrolyte fuel cell (PEFC)

PEFC is a type of fuel cells that uses a polymer film as the electrolyte. Hydrogen is ionized and the hydrogen ions pass through the electrolyte, reacting with oxygen and generating electricity.

Principles for Responsible Investment (PRI)

PRI are principles launched in 2006 by the UN Secretary General at the time, Kofi Annan. They were established through a joint collaboration between the United Nations Environment Programme Finance Initiative (UNEP FI) and the United Nations Global Compact to ensure institutional investors take environmental, social and corporate governance (ESG) issues into account in investment decisions.

PRTR Law Act

PRTR stands for Pollutant Release and Transfer Register, and is an abbreviation for the Law Concerning Reporting, etc. of Releases to the Environment of Specific Chemical Substances and Promoting Improvements in Their Management, which was promulgated in 1999. The PRTR system (Pollutant Release and Transfer Register) is a system under which businesses that handle more than a specified amount of a target chemical substance (Class I Designated Chemical Substance) notify the government of the amount of emissions, etc. 462 chemical substances are designated as Class I Designated Chemical Substances.


Replacing pipes without excavation

This is a method of burying polyethylene (PE) pipes in which only each end of the construction stretch is excavated. Not only does this these methods result in less excavated soil, it they also reduces the impediment of traffic around the construction site.


Sand blasting

Sand blasting occurs when high-pressure fluid is blown out from a water pipe buried underground. Sand particles blown off by the water squirting out of the pipe hit the gas pipe buried adjacent to the water pipe, and wear down and break through the gas pipe wall, and eventually water penetrates into the gas pipe.

SASB Standards

SASB is an abbreviation for Sustainability Accounting Standards Board, which sets disclosure standards for ESG factors that are expected to have a high financial impact in the future, with the aim of contributing to improving the quality of corporate disclosure and contributing to investors' decision-making from a medium- to long-term perspective. After the establishment of the SASB, the SASB Standards were developed through a series of evidence-based analyses and discussions among practitioners, companies, investors, academics, and others, and identify sustainability issues that are likely to have a high impact on the financial performance of companies in each industry. SASB Standards are based on the following principles.

Shale gas

Natural gas extracted from shale formations formed by the accumulation of muddy soil. Reserves are believed to be abundant in many parts of the world, and production in the U.S. is increasing.

Shallow pipe installation method

A method of placing pipes shallow underground. Like the Vermeer method, this method reduces the amount of excavated soil generated when burying gas pipes.

Solid oxide fuel cell (SOFC)

SOFC is a type of fuel cells that uses ceramic as the electrolyte. The oxygen is ionized and the oxygen ions pass through the electrolyte, reacting with hydrogen and generating electricity. A unique feature of SOFCs is that they can use carbon monoxide (CO) as well.



Task Force on Climate-related Financial Disclosures. Established in 2015 by the Financial Stability Board to discuss how the financial sector should consider climate-related issues; in 2017, it issued recommendations (TCFD recommendations) to support and encourage corporate climate change-related disclosures.


United Nations Global Compact

The initiative was proposed by Kofi Annan, then Secretary-General of the United Nations, to corporations at the World Economic Forum in 1999. It requires companies to comply with and practice the 10 principles on human rights, labor, environment, and anti-corruption.

Unused energy

Energy previously not made use of; for example, household wastewater, industrial water and sewage water, river and ocean water, waste heat from substations and factories, and waste heat from the cooling and heating systems of subways and underground malls.

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