Bottom-up Analysis of GHG Emissions from Shipbuilding Processes for Low-carbon Ship Production in Korea
Authors: Chung Yongjoo , Paik Chunhyun , Kim Hugon , Kim Young Jin 
Published: July 2017

There are two types of approaches for analyzing various aspects related to green-house gas (GHG) emissions, i.e., top-down and bottom-up approaches. Although the top-down approach focuses on macro-economic perspectives, the bottom-up approach is more suitable to investigate GHG emissions at an industry level utilizing domain-specific knowledge. For example, a bottom-up analysis requires a wide variety of data such as energy demands, conversion factors, and energy efficiency, which may be obtained by analyzing industrial process data. This study aims to provide a bottom-up approach for analyzing GHG emissions from shipbuilding processes in Korea. Reference energy system and energy balance for shipbuilding processes are derived for bottom-up modeling. Based on the midterm forecast on energy demands of the Korean shipbuilding industry, it is shown that the business-as-usual GHG emissions may be obtained. Relevant mitigation measures are then investigated to analyze their mitigation potentials for low-carbon ship production.

1. Introduction
Global climate change has recently drawn an increasing attention due to its adverse effects on our environment. Since the inception of Kyoto Protocol to the United Nations Frame-work conventions on climate change, local and international experts have long called for more international cooperation in coping with global warming. The main idea of international cooperative efforts is to impose binding obligations for greenhouse gas (GHG) emissions on participating countries. Even though some countries have withdrawn their commitment and others have been reluctant to adopting definite targets for emission reduction, many countries have already established a designated national authority to manage their GHG emissions. Korea has also established a national authority called "GHG Inventory and Research Center (GIR)" in 2010. One of the most important roles of GIR is to manage the national GHG emission levels and set the abatement target of various sectors through an efficient and integrated management of GHG-related information. Recently, GIR has conducted a series of research projects to analyze GHG emissions of industrial sectors in cooperation with a group of experts. This study presents the results from the analysis of GHG emissions and mitigation potentials for the shipbuilding processes in Korea. It should be noted that the scope of this study is limited to constructions processes in a shipyard even though the shipbuilding industry may encompass a broader range of industrial sectors such as steel production and transport. Adopting Model for Energy Supply Strategy Alternatives and their General Environmental Impacts (MESSAGE) developed by International Institute for Applied Systems Analysis in 1980s (Messner 1997), a bottom-up mathematical programming model is generated to derive the business-as-usual (BAU) GHG emissions in the construction processes in a shipyard. Abatement potentials of several technical abatement measures are also analyzed to help shipbuilders effectively cope with the issue of climate change.