Sumitomo Metal Mining : Installation of binary power generation equipment in Hishikari Mine

March 10, 2021

Listed Company Name: Sumitomo Metal Mining Co., Ltd.

Code:	5713
Representative:	Akira Nozaki, President and Representative Director
Contact:	Hideaki Kusanagi, Public Relations & Investor Relations Department
TEL:	[phone]

Installation of binary power generation equipment in Hishikari Mine

Sumitomo Metal Mining Co., Ltd. (Head office: Minato-ku, Tokyo; President & Representative Director: Akira Nozaki) has installed captive consumption binary power generation equipment at the Hishikari Mine that utilizes hot-spring heat. In February of this year, we began operation of this equipment. This is a captive consumption system, where the power generation equipment utilizes heat from the hot-springs that spout underground at the Hishikari Mine to generate electric power that is then used within the Hishikari Mine. Through generating power using naturally occurring hot-spring heat, weʼre able to reduce our greenhouse gas emissions.

Weʼre using a pump to draw, at a rate of 9,000 liters per minute, hot-spring water that spouts underground at the Hishikari Mine. About two-thirds of that water is cooled, processed and discharged into rivers, and the remaining one-third is supplied to local hot spring inns and other recipients through a public-private joint venture. At present, the orebody development going on at a deeper level at the Hishikari Mine is bringing changes to the locations of the hot springs, and this is raising the temperature of the water. This requires that we cool the water so that we are able to supply it at the same temperature as it has been in the past. We looked into ways to cool the water, and we decided to install binary power generation equipment that could effectively utilize the hot-spring heat. The generated power is 570,000 kwh a year, equal to about 2% of the overall power consumption at the Hishikari Mine.

For the installation of this equipment, we entered into a lease contract with Sumitomo Mitsui Finance and Leasing Company, Limited (Head office: Chiyoda-ku, Tokyo; President: Masaki Tachibana), and their cooperation allowed us to secure a business grant under the "Subsidy for Carbon Dioxide Emission Control Measures Project Cost"

program of the Japan Environment Association, reducing installation costs. The engineering and construction of this equipment was conducted by Daiichi Jitsugyo Co., Ltd. (Head office: Chiyoda-ku, Tokyo; President: Ichiro Uno).

Through the introduction of this equipment, weʼre engaging in initiatives towards becoming a company that actively undertakes climate change countermeasures, by reducing emissions and stably supplying products contributing to a low-carbon society, to achieve zero emissions of greenhouse gases (GHGs), as laid out in one of the material issues, climate change, in our Vision for 2030.

※Binary power generation equipment

※Mechanism of binary generator

*Reference

・Vision for 2030: Image for achievement of the Vision

・Vision for 2030: 11 Material Issues and our Vision