Comparison of Annual Energy Consumption and CO2 Emission

The annual energy consumption and CO2 emission were calculated based on ECO-2 analysis, and the energy consumption was calculated by converting it into the used amount of energy. It is necessary to understand the terms of primary energy consumption and the energy consumption. Energy consumption refers to the actual amount of energy required for equipment (cooling and heating equipment, hot water supply, ventilation and lighting equipment). The value calculated by converting the energy consumption into the primary energy is the primary energy consumption (= energy consumption × primary energy conversion factor for each source). Tables 10 and 11 present comparisons of the annual energy consumption and CO2 emission for the existing model and the improved model, respectively.


**Table 6.** Key input values for

'ECO-2'—Existing

 model.


**Table 8.** Key input values for 'ECO-2—Improved model.


**Table 9.** 'ECO-2 results of analysis—Improved model.

**Table 10.** Comparison of annual energy consumption and savings.


**Table 11.** Comparison of annual CO2 emission.


The energy consumption and CO2 emission results in Tables 10 and 11 may have varied depending on the usage profile of ECO-2 (Regulations on Operation of Energy Efficiency Rating in Buildings, Annex 2) [42] and the actual building usage time and pattern, equipment efficiency, etc. However, ECO-2 is currently the only officially approved building energy performance evaluation tool in Korea, and it is generally used to estimate building energy performance and energy usage in the building planning stage and related research fields.
