Hemp concrete walls: evaluation of the relationship between CO2 and TVOC

Climate change is driving the construction sector to use of more environmentally friendly and sustainable materials. Hemp concrete has been recently adopted as an innovative solution by the building industry to reduce emissions, as this material stores more CO2 than the emitted during its production. Part of this storage occurs during its service life leading to a reduction of indoor CO2 levels. CO2 has been widely used as a proxy for evaluating indoor air quality (IAQ).

A qualitative evaluation of the resiliency of Personalized Environmental Control Systems (PECS)

A Personalized Environmental Control System (PECS) aims to condition the immediate surrounding of occupants. This approach is fundamentally different from typical HVAC systems, which aim to create uniform indoor environments, regardless of the occupant preferences. PECS has several advantages including allowing occupants to adjust their immediate surroundings according to their preferences, which could improve their satisfaction with the indoor environment, and may lead to higher productivity.

Past and Recent Developments of Personalized Environmental Control Systems

Personalized Environmental Control Systems (PECS) condition the immediate surroundings of occupants, and they are expected to provide increased comfort, health, and productivity. Studies have reported on their benefits and limitations in addressing individual Indoor Environmental Quality (IEQ) factors, especially in terms of thermal comfort and indoor air quality. The COVID-19 pandemic and risks associated to climate change, such as heat waves, highlight the necessity for PECS that can address multiple IEQ factors.

Advantages and limitations of Personalized Environmental Control Systems (PECS)

Personalized Environmental Control Systems (PECS) with the functions of heating, cooling, ventilation, lighting, and acoustics have the advantage of controlling the localized environment at occupant’s workstation by their preference instead of conditioning an entire space. This improves personal comfort, health of the occupants, and energy efficiency of the entire heating, ventilation and air-conditioning (HVAC) system substantially. Some of the major advantages and limitations of PECS are summarized. 

Introduction to IEA EBC Annex 87

Personalized Environmental Control Systems (PECS) have advantages of controlling the localized environment at occupants’ workstation by their preference instead of conditioning an entire room. A new IEA EBC Annex (Annex 87 - Energy and Indoor Environmental Quality Performance of Personalised Environmental Control Systems) has recently started to establish design criteria and operation guidelines for PECS and to quantify their benefits. This topical session will provide an introduction to the objective/scope, activities, and intended outputs of the annex. 

The role of ventilation on aerosolized virus in multizone buildings

Ventilation of buildings is a good way of preventing transmission of some virus in aerosolized form as the SARS-CoV-2. In many buildings, prevention strategies as window opening and sealing door have to be considered with a multizone approach. Approach. We modelled a residence equipped with a exhaust-only ventilation system where a family is isolating in a pandemic context, with one infected person. We modelled and analysed the impact of opening the window and sealing the door in the quarantine room on exposures. We tested several window- and door-opening strategies. Results.

Comparing indoor air quality in naturally ventilated and air-conditioned hospitals in the tropics

Occupant exposure to airborne pathogens in buildings can be reduced by a variety of means, including adequate provision of outdoor air by ventilation. This is particularly important in buildings, such as hospitals, which may house a higher number of infected individuals relative to the wider population. In tropical Africa, however, there is evidence that new hospitals built with air-conditioning to cope with the extreme heat are poorly ventilated compared to existing hospitals that were designed to be naturally ventilated.

Advanced Optimal Control of Indoor Environmental Devices for Indoor Air Quality Using Reinforcement Learning

This study aims to develop and evaluate an advanced control method for acceptable indoor air quality (e.g., particulate matter and CO2) with low energy consumption in a residential space. A ventilation system, an air purifier, and a kitchen hood system are installed in the testbed to maintain a healthy IAQ. To accomplish the objective, we use a double deep Q-network (DDQN) which is one of the reinforcement learning. This study utilizes a co-simulation platform with EnergyPlus and Python.

Monitoring of air quality and indoor environment in rooms occupied by houseplants

The present paper describes an experimental test to identify the possible influences that the presence of plant species may have on the environmental quality of indoor spaces. For this purpose, a selection of houseplants with high air purification capacities was made based on existing literature (Sansevieria, Poto, Spathiphyllum, Ficus Benjamina, Kentia and Areca). Two adjacent rooms within an experimental building were used as test cells. The two rooms have similar characteristics. One room was occupied with the plants and the other was left empty.

Sensitivity analysis of inhabitant behaviour on the performance of ventilation systems

In this study, a sensitivity analysis on the effects of inhabitant behaviour on the performance of ventilation systems is carried out. Inhabitants behave differently in terms of presence at home, window opening, door opening, etc. Relating to the ventilation system, this is reflected in the ventilation demand and consequently the energy consumption, but also in the indoor air quality. Therefore, care should be taken to compare ventilation systems to each other as the inhabitants can be the most determining factor for the performance.