Abstract
Increased energy prices and trying to decrease environmental loads have created many efforts to reduce the amount of energy consumption in buildings, and many countries are conducting researches on passive houses, low-energy buildings and zero-energy buildings actively. The concept of 'zero energy' is different by countries or institutions due to differences in points of view and a general consensus has yet to be reached. However, they all share the basic idea of reducing a building's energy consumption to zero, without energy supply from outside. In the field of housing, houses have already appeared yearly energy use is zero, however, commercial buildings have diverse forms and lots of energy use and therefore it is expected that such requires a different approach from housings. On the other hand, concerning about building energy consumption, Korea government is operating a 'Assessment Project for Building Energy Certification' program, which is evaluated by cooling, heating, ventilation, lighting and hot water energy for unit area annually using the ECO2 program from 2009 This study conducted reviews on the energy consumption of buildings with ECO2 program and base model which is assumed typical type of office building. And it suggests active and passive methods technologies to save energy consumption and renewable system as PV, winds etc. to generate electric power, too. Passive method and Active methods with renewable system can reduce around 23%, 61% of energy consumption respectively compared to base model, which uses about $504kWh/m^2$ annually. The technologies combination may help architects and buildings' owners to make a decision how to save energy and adapt the their strategies.
