Abstract

CO₂-based demand-controlled ventilation (DCV) has been proved to be energy-efficient by altering ventilation rates according to surrogated indications of CO₂ levels in single- and multiple-zone single-path variable air volume (VAV) systems. However, DCV for multiple-zone VAV systems with multiple recirculation paths is still untapped. Multiple-zone VAV systems with series and parallel fan-powered terminal units (FPTUs) are studied in this study. Energy and ventilation performance of the DCV strategies with dynamic resets are evaluated. The DCV control sequences for FPTUs are first summarized. A co-simulation approach combining EnergyPlus with CONTAM is adopted. The DCV controls are implemented in the EnergyPlus energy management system (EMS) module. New EnergyPlus EMS actuators are added and a customized EnergyPlus module is built to achieve the DCV control for each system. An office building is used to demonstrate the benefits from the proposed DCV strategies in four different U.S. climates zones. Two baselines for ventilation requirements (ASHRAE 62.1, California Title 24) are considered. The proposed DCV strategies resulted in 7–14% and 7–21% HVAC energy savings for each system, on a source energy basis, compared with the baseline of a simplified ASHRAE 62.1 approach. Both systems could achieve good compliance with the ventilation requirements in ASHRAE Standard 62.1.

摘要

通过根据CO _2的替代指标改变通风速率，已证明基于CO ₂的按需控制通气（DCV）是节能的单区和多区单径可变风量（VAV）系统中的水平。然而，具有多个再循环路径的多区域VAV系统的DCV仍未开发。在这项研究中，研究了具有串联和并联风扇供电终端单元（FPTU）的多区域VAV系统。评估具有动态重置的DCV策略的能量和通风性能。首先总结了FPTU的DCV控制序列。采用了将EnergyPlus与CONTAM相结合的协同仿真方法。DCV控制在EnergyPlus能源管理系统（EMS）模块中实现。添加了新的EnergyPlus EMS执行器，并构建了定制的EnergyPlus模块，以实现每个系统的DCV控制。在美国的四个不同气候区域中，使用一栋办公楼来演示拟议的DCV策略的好处。考虑了两个通风要求基线（ASHRAE 62.1，加利福尼亚州标题24）。与简化的ASHRAE 62.1方法的基准相比，基于源能源，建议的DCV策略使每个系统的HVAC能源节省7-14％和7-21％。两种系统都可以很好地符合ASHRAE标准62.1中的通风要求。