Cooling, Lighting & Transport

The largest energy consumption for an office is for its cooling and lighting, which normally account for 50% - 60% and 25% - 30% of total energy consumption respectively. The rest of energy use is for pumps, motors and lifts for vertical transport. Finally, energy is used for office equipment, the plug loads.

Apart from being free, daylight is also a very efficient light source, measured in light (lumen) received compared to the unwanted heat (watts) that accompanies the light. Diffuse daylight with an efficiency of around 120 lumen/watt is twice as good as traditional fluorescent lighting around 60 lumen/watt.

In the LEO Building, high efficiency light fixtures are installed.

This, in combination with a reduction of the illumination in offices according to the new standard, reduces the installed lighting load from typically 20W/m2 to only around 10W/m2. The illumination level is reduced from 500lx to approximately 335 lx in the office space.

The mechanical and electrical (M&E) equipment for the building also include high efficiency motors (HEMs) for pumps and fans, with variable speed drives (VSDs) for optimum operational efficiency. The VSD’s reduce motor power and electricity consumption drastically for part load condition, which is the normal load condition.

Each floor has its own air handling unit (AHU) and it is subdivided into smaller zones, where the provision of chilled air is controlled with a Variable Air Volume (VAV) damper. The VAV damper controlled. The VAV damper controls the chilled air volume to the zone according to the temperature setpoint.