Human behaviour-dependent and variable-flow-reversible mechanical ventilation system design in an underground parking facility

Abstract

Fixed air change ventilation in a huge underground parking facility is a major energy consumption for a building. Variable and unidirectional flow and control by carbon monoxide (CO) sensors in a parking facility can help to reduce energy consumption. However, obstructions in the parking facility reduce the effectiveness of uni-directional flow. Also, siting of CO sensors at particular positions may not accurately reflect the CO level throughout the whole parking facility. This study proposes two energy-efficient approaches. The first approach is to reduce the ventilation rate based on the number of cars, which is determined by a parking guidance system. The second approach is a reversible zonal control system in relation to the human behaviour. Parking bays near access lobbies are always favoured. This behaviour is used to determine ventilation zoning. For commercial buildings, cars are parked for long periods of time, where CO and heat generated by cars can be removed within a certain period of time. All fan shafts are designed for zonal control and reversible mode, dynamically operated to effectively remove hot and contaminated air. This reversible zonal control system can remove the heat effectively within a shorter time, thus improving energy savings.