No abstract

Lean production is a systemic approach to meeting customer expectations, whatever they value, by reducing waste. At first glance, lean then could only contribute to sustainability, while sustainability is achieved only if the customer values sustainability. The paper has two objectives. One is to examine whether sustainability is feasible using lean production with sustainability as an added value. The second objective is to examine how current lean construction tools and methods impact the construction and operation of sustainable facilities. The authors also suggest how these lean construction tools and methods have evolved to contribute to green construction. For this study, the authors interviewed lean adopters and conducted literature surveys on lean principles and methods, and its impacts on the economic, social and environmental sustainability.

Greenhouse gas (GHG) emissions, which are produced through the combustion of fossil fuels, cause climate change. Unfortunately, South Korea is highly dependent on fossil fuels because of its industrial nature. However, many islands in South Korea have the potential to generate a considerable amount of renewable energy, which should be studied. KEPCO (Korea Electricity Power Corporation), which runs micro-grid facilities in Gasado Island in Jindo, South Korea, built micro-grid facilities in Mozambique in 2015. The micro-grid construction of Gasado Island is considered one of the most successful micro-grid projects of KEPCO, so KEPCO is hoping to expand energy development overseas and become a top-tier global power company. This study aims to find a more technologically and economically optimal hybrid energy system for Gasado Island that KEPCO should have built. We also compared this optimal solution to the Korean government plan. The Korean government plan is the same as the KEPCO plan because KEPCO is classified as a market-oriented public corporation under the Act on the Management of Public Institutions. In the final section of this paper, both the implications and limitations are discussed in detail.

In the on-site rebar delivery system, as the common method of rebar supply in the construction industry, reinforced steel bars are delivered in large batches from supplier's facilities through contractor's warehouse to the construction site. Rebars are then fabricated on-site and installed after assembly. In the new delivery system, called prefabrication Just-In-Time (prefab-JIT) system, the off-site cut and bend along with frequent rebar delivery to the site are applied in order to improve the process and increase its efficiency. The main objective of this paper is to assess and compare the environmental impacts resulting from the air emissions associated with the two rebar delivery systems in a case study construction project. Environmental impact categories of interest include global warming, acidification, eutrophication, and smog formation. A process-based cradle-to-gate life cycle assessment methodology is applied to perform the analysis. The results show that the prefab-JIT rebar delivery system causes less contribution to all mentioned environmental impact categories compared with a traditional on-site delivery system.

No abstract