The government of Thailand legislated an Energy Conservation Promotion Act (ECP Act) in 1992 and set bye-laws that identify designated buildings (DBs) and detail mandatory requirements for energy conservation for DBs in 1995. An Energy Conservation Promotion Fund (ENCON Fund) was also created to fund energy audits on 1900 DBs. Recently the requirements and procedures for energy conservation in buildings have been revised where system performance requirements for building envelope, lighting, air-conditioning, and hot water generation are adopted. Moreover, the new building energy code (BEC) distinguishes different categories of DBs, provides credit for use of solar energy, and introduces a new option of whole building energy compliance. The authors develop building models from data obtained from energy audit reports and use them to estimate savings on energy and peak demand from future new buildings using forecasted energy and peak demand data from the Load Forecast Subcommittee, a panel tasked to forecast future electric load of Thailand. From a modest level of energy saving in the first year that the code is expected to be enforced, the level of saving rise to over 10% and 20% annually of requirement of target buildings in 6 and 12 years respectively. (C) 2010 Elsevier Ltd. All rights reserved.