Figure 4. Solar Radiation analysis for the Pertamina Campus

3.3 Form and function

The orientation of the tower is the first step towards maximizing environmental gain and reducing financial investment. Considering base building orientation along the direction of the sun, i.e., East-West, the façade receives a total solar radiation of 111 GWh per square meter. Rotating the building along the North-South axis reduces the total radiation by 10% (See Figure 4).

Inferencing from the psychometric chart, the tower will benefit from planning shading devices on all façades. The system can be different for East-West and North-South respectively because of the varying radiation values. Radiation on East & West facades exceeds 950 kWh per square meter. Planning horizontal shading devices will bring down the total radiation by 25% (to 82.5 GWh per square meter) of the base value, whereasvertical shading brings down the total radiation by 35% (to 75 GWh per square meter) (See Figure 5). Planning vertical shading on East-West façade will reduce the demand for mechanical systems.

Radiation on South Facade facades exceeds 950 kWh per square meter. Planning horizontal shading devices will bring down the total radiation by 61% (to 44 GWh per square meter) of the base value, whereas vertical shading brings down the total radiation by 58% (to 47 GWh per square meter) (Figure 6). Planning horizontal shading on North-South façade will further reduce the demand for mechanical systems.