Environmental, Social and Governance (ESG) information

Major Business Activities and Environmental Initiatives

Main business operations
Fuel procurement

To further strengthen competitiveness and flexibility in fuel procurement, Kyushu Electric Power is engaged in diversification of fuel procurement, participation in resource development and production projects and the introduction of fuel trading (adjustment of fuel volume and price management). We strive for cost reduction in fuel transportation by using our own LNG tanker and chartered ships for shipping.

Fuel procurement status (FY2017)
Power generation

In order to secure a stable supply of energy over the long term, counter global warming, and provide electric power at low cost, we generate power while taking the environment into account and using a balanced combination of various power sources. To this end, we employ a wide range of approaches, including promoting nuclear power predicated on safety, actively developing renewable energies such as solar, wind and geothermal power, using these renewables to the maximal extent, and improving the efficiency of thermal power.

Composition of capacity for all facilities (GW) (Including power purchased from other companies) (as of March 31, 2018)

(Note) Energy source composition for the company’s own facilities. Please see the Kyushu Electric Power website for information about the retail power business guideline-based power supply structure for electricity sales volume.

Power transmission and distribution

We deliver electricity by transmitting it at high voltage from power stations to substations, lowering the voltage at substations, and sending it along distribution lines to places such as homes and factories. To be able to deliver a low-cost, stable electricity supply to support Kyushu’s industries and lifestyles, we operate a stable electricity system and preserving steady transmission and distribution facilities.

Power transmission, transformation and distribution equipment (as of March 31, 2018)
Transmission Length of transmission lines 10,773 km
Supporters Steel towers approx. 25,000
Others (concrete poles, etc.) approx. 42,000
Transformation Number of substations 596
Capacity 74,430,000 kVA
Length of distribution lines 141,730 km
Distribution Supporters Concrete poles approx. 2,411,000
Others (steel towers, etc.) approx. 42,000
Energy services

We provide various energy services that respond to the diverse needs of customers, including proposals for rate plans and services meeting the requirements of household customers and one-stop energy services for corporate customers.

Electricity sales volume

Note 1: Specified-scale demand is 6,000 V or higher at standard voltage and 50 kW or higher of contracted power
Note 2: Display categories changed from fiscal 2017

Proactive Development and Full Adoption of Renewable Energy Options

The Kyuden Group is working to develop and incorporate renewable energy as part of our operations, recognizing its terrific potential as a source of domestically produced energy which can be effectively utilized, as well as a means of fighting global warming. We are undertaking a variety of renewable energy projects through which we seek to develop 4 million kW of renewable energy (2.04 million kW more than currently) domestically and overseas by 2030, focusing primarily on geothermal and hydroelectric energy.

Tidal Power Demonstration Project

Technologies that use the incoming and outgoing motion of tides to generate electricity are ideal for an island nation like Japan and have minimal environmental impact. This testing facility is aimed at developing this new form of renewable energy power generation.

Japan’s first commercial-scale tidal power generation demonstration project

Kyuden Mirai Energy is part of a consortium with three partners including the Nagasaki Marine Industry Cluster Promotion Association that was selected for the Project for the Promotion of Practical Applications of Tidal Power Generation Technology in 2016. At present, the consortium is designing instruments based on tidal studies with the aim of developing a commercial-scale (2,000 kW-level) tidal power generation facility at Naruseto off the coast of Goto City, Nagasaki Prefecture. Testing is scheduled to start in 2019.

Maximal Purchasing of Electricity Generated from Renewable Resources
Configuring to maximize generation and use of renewable energy sources

We strive to make and buy as much electricity as possible from renewable energy sources like sunlight and wind, but these are limited by weather conditions and time of day, so where necessary we augment them with in-house thermal and pumped-storage hydro power generation facilities.
Also, the Buzen Power Station is home to the Buzen Storage and Transformer Substation, one of the world’s largest-capacity storage battery systems, which is capable of storing 300,000 kWh and has an output capacity of 50,000 kW. The substation was established in March 2016, and helps balance demand and supply by storing energy into the batteries or discharging it in response to solar energy output.
Moreover, in order to make more accurate predictions of generation from renewable energy sources, we use satellite images to estimate sunlight and make output projections, and are developing wind speed models.

Demand and Supply Results for May 3 (Thurs), 2018

Around 80 percent of the electricity supplied to customers between 12 p.m. and 1 p.m. was solar power, the highest ratio of solar power to overall demand we have achieved so far.

Hydroelectric Pumped-Storage
Generation System

Two large regulating reservoirs are created at a power station, one above and one below the facility. When demand is high, water in the upper reservoir is released, and its momentum as it flows down into the lower reservoir is used to generate electricity. Then, when the supply of electricity is higher than demand, the surplus is used to drive the pumps that return the water to the upper reservoir.

A substation with batteries that can store enough electricity to power 1,000 homes for a month

The Buzen Storage and Transformer Substation was built to improve the balance between supply and demand. With 252 sodium-sulfur (NAS) batteries,* the substation is able to store enough electricity to power a thousand regular households for a month (300,000 kWh), and has an output capacity of 50,000 kW.
In practice, electricity is utilized efficiently by storing energy during the hours when solar power generation increases (between 9 a.m. and 3 p.m.), discharging it during darker hours when power consumption, such as for lighting, is higher.

Regulating Supply & Demand

*NAS batteries are storage (secondary) batteries that use the chemical reactions between sulfur and sodium ions to charge and discharge electricity. They are smaller than lead batteries and last longer.

Demonstration Project Aimed at Improving Demand and Supply Balance

In June 2018, a group of five companies—the Central Research Institute of Electric Power Industry, Nissan Motor, Mitsubishi Motors, Mitsubishi Electric, and Kyushu Electric Power—began testing*1 “vehicle-to-grid” (V2G)*2 technology, which seeks to use electric vehicles as a means of regulating the balance between electricity demand and supply.

*1 The testing project is partially funded by the government through the Ministry of Economy, Trade, and Industry, Agency for Natural Resources and Energy’s Project for Testing Virtual Power Plants*3 that Use Demand-Side Energy Resources.
*2 Vehicle-to-Grid systems take energy stored in electric vehicle batteries to power the grid.
*3 Virtual Power Plants are systems that use high-level aggregation technology to manage the discrete energy sources in homes, factories, and other such facilities remotely via the Internet of Things in order to regulate the balance of electricity demand and supply.

Renewables integration

According to World Energy Outlook 2018, it referred to the integration of variable renewable energy sources into electricity system in Kyushu, Japan as the following.

“Continued cost reductions and policy support are driving sustained uptake of wind power and solar PV across the World. The integration of variable renewable energy source (VRE) into electricity systems can be categorized into six distinct phases, which can help to identify relevant challenges and integration measures. The categorization not only depends on the share of VRE,but also on technical and other characteristics of the systems.”

Figure Characteristics and key transition challenges in different phases of integration of renewables (Referring to World Energy Outlook 2018)

Key challenges by phase in moving to higher levels of integrating variable renewables in power systems

“VRE determines operational pattarns of the power system in Phase 3. Electricity suppky has an increased level of uncertainly and variability owing to a higher share of VRE (typically higher than 10%) . System flexibility becomes very important for integrating VRE to address greater swings in the supply-demand balance. Countries and systemns that are in Phase 3 include Germany, Italy, Kyushu (a subsystem in Japan) and the United Kingdom.”

“For example, the overall power system in Japan is in Phase2, but Kyushu, a large island located in the southwest, has a higher share of VRE and faces Phase 3 problems. On Kyushu, the instantaneous PV penetration in certain periods is about 80% of electricity demand. This has motivated the development of cost-effective operational approaches to optimize the exisiting resources including thermal plants, reservoir hydro and pumped storage hydropower plants.”

Figure Annual share of variable renewables generation and related integration phase in selected regions / countries, 2017 (Referring to World Energy Outlook 2018)

Many regions are in phase 1 and 2, with a handful in phase 4

Initiatives toward “low-carbon” coal-fired thermal power generation

We continue to promote the development of technologies aimed at creating a “low-carbon” method of coal- red thermal power generation, which remains an economically superior option and has plentiful resources available.

Utilizing state-of-the-art technology and promoting technical development
New technologies will give our new coal-fired thermal power generator potential for further reductions in environmental impact

Matsuura Power Station Unit 2, which is currently under construction and scheduled to commence operations in December 2019, uses ultra-supercritical pressure milled coal, which involves new technology that boasts high thermal efficiency and reduces fuel consumption, thereby making it possible to reduce the facility’s environmental impact.

Overview of matsuura power station unit 2 development
Output 1 million kW
Power generation method Ultra-supercritical pulverized coal combustion
Fuel Coal
Thermal efficiency at the generating end (lower calorific value standard) 45% or more
CO2 emission reduction through operational technology
Biomass-mixed combustion helps coal-fired thermal power stations reduce CO2 emissions

Sewage Sludge Fuel Combustion at the Matsuura Power Station

Since April 2013, dewatered sewage sludge from the sewage biomass fuel conversion project undertaken in Kumamoto City has been mixed into the coal used to generate electricity at the Matsuura Power Station in Matsuura City, Nagasaki Prefecture. In FY2017, the annual reduction in CO2 emissions reached approximately 1,000 metric tons.

Woody biomass mixed combustion at reihoku thermal power station

The Reihoku Thermal Power Station in Kumamoto Prefecture hosted a demonstration project* between FY2010 and FY2014 trialling mixed combustion featuring woody biomass (i.e., mainly unused resources such as forestry residue). Today, woody biomass is added to the coal (up to one percent of overall weight) used to generate electricity and, in FY2017, the annual reduction in CO2 emissions reached approximately 9,000 metric tons.

*The Demonstration Project for Testing Forestry Residue Woody Biomass and Coal Mixed Combustion Power Generation in FY2009 was the recipient of a government grant.

Community activities : Landslide debris converted to woody biomass at Reihoku

The northern Kyushu area was devastated in July 2017 by torrential rains. The resulting landslides created a massive amount of driftwood. At Kyushu Electric Power, our Reihoku Thermal Power Station is helping to clear the mountains of logs by accepting these, chipping them on site, and using them for woody biomass-mixed combustion power generation.

  • Receiving, processing, and using driftwood