Overall Perspective of Environmental Impact

The diagram below shows aggregate inputs to and outputs from manufacturing operations of the entire NGK Group at all domestic and overseas sites in fiscal 2018.
Inputs represent data for raw materials and energy etc. and outputs for manufactured products and services as well as substances that are discharged into the atmosphere and into water.

Data up until fiscal 2017 covered only manufacturing bases, but from fiscal 2018 non-manufacturing bases were included in order to expand the disclosure of information.

NGK Group Material Balance (Input and Output)


  • A new calculation method has been adopted for NGK CO2 emissions on a non-consolidated basis. The calculation now uses the CO2 conversion factor determined in the Enforcement Ordinance for the Act on Promotion of Global Warming Countermeasures (revised in May 2016).
  • Environmental performance values in this report have been rounded off for convenience; therefore the sum of individual values may not match the totals.
  • "Discarded materials" indicates the total amount of industrial waste and valuables.

Preventing Global Warming

The NGK Group strives to reduce CO2 emissions, a major cause of global warming, by setting and working toward achievement of emission reduction targets. NGK is a member of the Japan Climate Leaders' Partnership (Japan-CLP), a business coalition in Japan that aims to create a low-carbon society through is engaged in decarbonizing business, trial business collaborations, policy creation and publicity activities, and cooperation with like-minded international organizations.

Reducing CO2 Emissions Associated with Manufacturing Activities

In fiscal 2018, the start of production at a new factory and, the commencement of mass production of new products, and a temporary decrease in demand for main products combined to present difficulties in our efforts to reduce CO2 emissions. As a result, we were unable to achieve the target for CO2 emissions per unit of net sales that we set under the Five-Year Action Plan.
Furthermore, due to the effects of a drop in production volume, there was a worsening of the reduction rate against BAU, an indicator newly introduced under the Five-Year Action Plan to help visualize the effect of measures to reduce emissions.

CO2 emissions / basic unit per net sales* (NGK Group)

Basic unit per net sales calculated with the value in fiscal 2013 set at 100.

CO2 emissions / reduction rate against BAU* (NGK Group)

Reduction rate against BAU: The percentage rate of emissions reduction resulting from implemented actions against a computed value for the hypothetical absence of the actions.

Adoption of Environmentally Friendly Production Processes

Through the introduction of highly efficient equipment and the promotion of the collection and use of exhaust heat and improved production efficiency, the NGK Group makes efforts to reduce environmental impacts resulting from production. Also, our Reformed Manufacturing Structures aimed at enhancing competitiveness significantly contribute to the realization of eco-processes.
We will create further advanced eco-processes through our New/Reformed Manufacturing Structures.

Change in CO2 emissions from continuous kilns by year of introduction

Note: Change in CO2 emissions from continuous kilns, which constitute major production equipment

Measures to Reduce CO2 Emissions and Effects

As we continue to expand overseas manufacturing, the NGK Group is particularly striving to raise manufacturing efficiency at our overseas sites in order to reduce the CO2 emissions of the Group as a whole. We have made steady progress by introducing the innovative manufacturing processes and improvements to facilities and operations that we have implemented to date in Japan in our overseas manufacturing sites, as well as promoting energy-saving activities for general-purpose equipment.

In fiscal 2018, these initiatives achieved an annual CO2 reduction effect of approximately 13,700 metric tons (a reduction rate of 1.5%), 60% or more of which was achieved by improvements carried out at our overseas sites.

Promoting Effective Use of Resources

To boost yield from manufacturing process improvements, the NGK Group reuses in-process materials in an effort to curb discarded materials while also focusing efforts on recycling to reduce final disposal volumes to promote resource recycling.

Reducing Discarded Materials from Manufacturing Activities

In fiscal 2018, as with CO2, there were numerous factors that hampered waste reduction, such as the start of a new plant and the start of mass production of new products.
However, the basic unit per net sales steadily improved over the previous year, so were able to achieve our fiscal year target as well as the target under our Five-Year Plan ahead of schedule. This was thanks to the continuing improvement activities of our manufacturing divisions, such as improving the material utilization rate and production yield, and recycling within each process. Meanwhile, the reduction rate against BAU, which indicates the rate of improvement in the basic unit per production volume from the fiscal 2013 level, was 20%, thus falling short of the fiscal year target of 23%. This was due to a temporary drop in demand for some of the products for which we had achieved dramatic improvements. For fiscal 2019, we forecast volume to rebound to the levels of two years ago.

Amount of discarded materials generated / basic unit per net sales* (All NGK Group manufacturing sites)

Basic unit per net sales calculated with the value in fiscal 2013 set at 100.

Discarded materials / reduction rate against BAU* (All NGK Group manufacturing sites)

Reduction rate against BAU: The percentage rate of emissions reduction resulting from implemented actions against a computed value for the hypothetical absence of the actions.