Climate change has had a global environmental impact, necessitating concerted efforts to mitigate the subsequent damage. In the majority of such efforts, upper limits are set for greenhouse gas (GHG) emissions by utilities and industries, and exchangeable permits are made available to emitters in the form of allocations based on past emissions, auctions, or a combination of both. In this complicated atmosphere, the environmental problems related to climate change have turned into a sensitive international political topic that has been discussed at the United Nations General Assembly since 1988, and the threat of global warming has received increasing attention. In 1994, 150 countries made agreements under the United Nations Framework Convention on Climate Change (UNFCCC). Since then, the United Nations (UN) has held a UNFCCC convention annually. Because Taiwan is not a signatory nation to the Kyoto Protocols, we may not be "legally" compelled to obey the regulations on carbon dioxide reduction. However, the total production of GHGs by our country represents one percent of that for the entire world, and with respect to our responsibilities as members of the so-called "Global Village" and the restrictions of the international contract, it is truly wise to consider and develop measures for GHG reduction as soon as possible. To coincide with the co-related missions of being a "Healthy City," a "City of Continual Development", and the "Green Society City of Tainan," the Tainan city government has created a set of ideal institutional mission-statements called the "Healthy Continually Developing City" and has planned a series of GHG impetuses, which include pushing outreach activities on energy conservation and carbon dioxide reduction, such as environmentally-friendly hotels, green energy stores, energy conserving temples, vegetarian restaurants and waste reduction. Because of activities such as using the four methods of energy conservation at department stores and applying energy-conserving light sources at Ta-Tien-Hou temple, carbon emissions have been reduced to 1,176,792 kg (56.1%) and 148,016 kg (96.0%), respectively, per year. Crown Copyright (C) 2011 Published by Elsevier B.V. All rights reserved.