Abstract View
Novel Control Strategies for Indoor Filtration
TIANYUAN LI, Jeffrey Siegel, University of Toronto
Abstract Number: 459
Working Group: Indoor Aerosols
Abstract
Particle filtration systems are widely used indoors to reduce particle concentration and lower occupant exposure. Runtime, which is the fraction of the operation time of the systems, influences the amount of air passing through the system. While increasing the runtime can improve the removal performance of filtration systems, it also increases the energy consumption of the fans. Thus, strategies are needed to improve filtration performance while reducing runtime and conserving energy. In this work, we simulated concentrations using time-varying mass balances of residential indoor environments with stochastic emission events. The exposure reduction, a metric for filtration effectiveness, and removal efficacy, the ratio of exposure reduction to runtime, is calculated to provide a quantitative assessment on four operation strategies. These strategies are sensitive to concentration and/or presence of emission events, pulsing the filtration system regardless of concentration, and pulsing during elevated concentration periods (i.e., a hybrid strategy). The results show that the concentration strategy, which synchronizes operation with high indoor concentrations has the highest removal efficacy. It could achieve a comparable level of exposure reduction as continuous operation, but with runtimes as low as 80%. Adding emission event detection to the concentration strategy did not lead to substantial improvements. The hybrid strategy could further reduce the runtime of the concentration strategy by pulsing but at a cost of decreased exposure reduction. In homes in regions with low ambient concentration but strong indoor emission events, the concentration strategy could save approximately 100 kWh of fan energy over 3 months for efficient fans, and more than 200 kWh for conventional fans. The results show that the concentration strategy provides opportunities for households to regulate indoor concentration while conserving fan energy use.