Published: 15 Sep 2021

One of the crucial issues in sustainable manufacturing highlighted by mechanical engineers is the issue of energy. This is indeed an important issue. No machine can ever work without energy. The world can stop spinning if it runs out of energy.

Currently, the world's primary energy sources are still non-renewable resources, commonly referred to as fossil energy, such as oil, coal, gas, and nuclear. According to the 2014 world energy statistics published by the International Energy Agency, the contribution of fossil energy is still 86%. So, only 14% of the world's energy comes from sustainable energy sources.

Conditions in 2020 have not changed much. For example, in the United States (US), a country that consumes 25% of the world's energy, 85% of its energy supply is still sourced from fossil energy. How about Indonesia? The government targets the use of New  Renewable Energy (NRE) to reach 23% by 2025. Until now, Indonesia's achievement is only half, namely 11.5%. With four years remaining, Indonesia needs to work hard to achieve this target.

This condition has attracted the attention of mechanical engineers, including Dr. Eng. Topan Setiadipura, senior researcher and head of research at the Advance Reactor Group. Even so, Topan sees that the Sustainable Development Goals (SDG) program launched by the United Nations can be a momentum for the world, including Indonesia, to encourage sustainable energy.

Topan also explained further the meaning of sustainable energy. "This is easy to access and can reduce poverty and inequality, support health, education, industry, and economic growth," he explained. Participating in realizing the SDGs program from the United Nations is a challenge for Indonesia. Topan presents several obstacles. For example, the distribution of electricity supply has not been evenly distributed.

The distribution of the availability of natural resources is also a problem. For example, South Sumatra is the province with the largest coal reserves in Indonesia (reaching 50.2 million tons), followed by East Kalimantan (48.2 million tons), West Kalimantan (22.8 million tons), and South Kalimantan (16.5 million tons). Coal reserves in other provinces in Indonesia are less than 5 million tons.

Another problem with the reserves of fossil energy sources. According to the Minister of Energy and Mineral Resources Arifin Tasrif, with the current level of consumption, Indonesia's crude oil reserves will run out in the next 9.5 years. Then, coal and natural gas reserves will run out in 19 years or 2040. This is not a long time. So, Indonesia needs to hurry to increase NRE production and, at the same time, direct its consumption to a green solution.

Practitioners and academics of mechanical engineering are now carrying out these various initiatives—for example, Dr. Eng. Sri Hastuty, a lecturer in the Mechanical Engineering Study Program, Pertamina University, looks at the use of tools. To optimize the electrochemical machining process parameters on stainless steel, namely Electrochemical Machining (ECM), the process uses DC (direct current) solutions and supply power. For the record, the use of DC as a power source is considered more stable than AC (alternating current).

Another initiative came from Ir. Muslim Mahardika, S.T., M.Eng., Ph.D., Lecturer of Mechanical Engineering Study Program, Gadjah Mada University, and his team. They are currently focusing on developing mechanical and medical manufacturing technology, some of which still have to be imported. These imports are very resource-draining.

Meanwhile, Djati Wibowo, Ph.D., a lecturer in Mechanical Engineering Study Program, Sampoerna University, noted the need for a more explicit legal basis for sustainable manufacturing. In Indonesia, there are still many people, including industrial practitioners, who are not aware of the importance of treating waste before it is disposed of. (JB Susetiyo and Lita Gabriella, PR team. Photo: Lita Gabriella)