Field measurements and case studies

Subtask 5: Field measurements and case studies

A summary of the Subtask 5 accomplishments

Subtask 5 included three activities:

The first activity was an analysis of the metrology resources necessary for the assessment of IAQ in residential buildings. This resulted in an overview report with the available measurement techniques for both IAQ and airflow measurements as well as guidelines on selecting the appropriate techniques for a field study.

The second activity consisted of carrying out experiments to provide validation data for digital models. Three levels of increasing complexity have been defined: a single highly controlled stainless steel test room with a source for a single pollutant, a small student studio with 3 selected materials for emissions and an occupied house (Figure 7 and Figure 8).

The last activity consisted of the compilation of IAQ measurement results in low energy consumption residential buildings in the form of a summary sheet including global building data (location, geometry, envelope structure, thermal and ventilation systems) as well as information concerning measurement equipment and levels of pollutant concentrations in these buildings. This summary sheet is intended to provide at-a-glance information on the case study to other researchers interested in the data and it is recommended to include this as a supplementary material in publications and reports. Annex participants have provided 7 examples of such summary sheets included in the report.



Figure 7: Spaces of the house (living room and dining room) during the experiment and evolution of the VOC concentration in the house.

Unresolved technical issues

ST4 and ST5 jointly addressed the use of cheap VOC sensors for monitoring purposes, but did not address the aggregation of this data using cloud based solutions. This IoT / big data application in IAQ is an emerging issue that provides challenges and a lot of opportunities to set up cross-sectional studies in the future.

Recommendations for follow-up work

Annex 68 provided a general framework for integrated simulation and assessment of energy efficiency (EE) and chemical indoor air pollution. This framework can now be expanded to develop and assess a series of intelligent IAQ management strategies.

In order to propose intelligent and energy efficient IAQ management strategies, a number of points must be developed:

-       Analyze the means of implementation of IAQ management strategies to resolve problems specific to the residential sector.

-       Determine the means of measuring the effects of the strategies applied (indicators of efficiency).

-       Adapt strategies to different climates, construction styles and practices in different countries (flexibility).

-       Implement the strategies for most residential construction projects without limiting them to development and avant-garde projects (generalization).

-       Check and test the strategies proposed by research studies or solid case studies.

Thus, the research group in Annex 68 proposes a follow-up to this work entitled 'Energy Efficient Smart IAQ Management for residential buildings'. In this new Annex, approved as Annex 86, it is proposed to optimize the energy efficiency of IAQ management by addressing the previous points. For IAQ management, the focus will be mainly on the use of active materials (materials that have the ability to actively influence IAQ in space) and intelligent smart ventilation, since these are the strategies that potentially have potential high energy efficiency.

By compiling existing work on sources of pollution in residential areas (including occupants' activities and the penetration of outdoor pollution), the objective is to define a framework for assessing the performance of different technologies in terms of energy efficiency, comfort and health of the occupants. These include extending the framework developed in Annex 68 to measurements of particles and energy efficiency, explicitly including humidity, temperature and ventilation rate control and modeling of HVAC components, as well as creating a common methodology for sharing IAQ data between smart devices. The pooling and analysis of data will help to better understand the range of conditions in housing and to identify the most appropriate and energy-efficient IAQ management strategies. The application of the assessment methodology over time will also allow the continuous commissioning of systems that directly influence IAQ, mainly but not exclusively ventilation. Another advantage is the ability to convey information to building occupants, building operators and facility managers in a consistent manner.

This proposal is focused on improving the energy efficiency of operating systems, but also and above all on improving the acceptability, control, quality of installations and long-term reliability of residential ventilation systems and other IAQ management strategies. Without good robust management of ventilation and IAQ over the lifetime of the devices, there is a risk to encourage a return to more primitive IAQ management strategies, which are less efficient both in terms of IAQ and in terms of energy efficiency.

Last, but not least, the Annex will include a specific task of developing modernization refurbishment solutions to implement intelligent smart ventilation functions in existing systems.

 

Contact

Jelle Laverge
Tenured Academic Staff
Ghent University
+32 (0)9 264 37 49
jelle.laverge@ugent.be

https://www.iea-ebc-annex68.org/subtasks/field-measurements-and-case-studies
22 APRIL 2021