energy consumption

Building energy behaviour and indoor environmental conditions have been changing due to different external events that have been taking place at global level from 2020, from the COVID pandemic (2020-2022) to the energy crisis (mainly from the war in Ukraine from February 2022). During these events, existing naturally ventilated (NV) buildings have had to balance minimum thermal comfort, high levels of ventilation (to reduce CO2 concentration and risk of infection) and the lowest energy costs.

Airtightness is of key importance, both for indoor thermal comfort and for energy efficiency of buildings. Although formally regulated by the rulebook on minimum energy efficiency requirements for buildings, airtightness is not properly addressed in practice in Montenegro. Airtightness measurements are not mandatory, so there is no data in this regard for the building stock so far.

Since 2018, Renson has introduced a range of cloud-connected residential ventilation systems, including central and decentral mechanical extract ventilation (MEV), as well as fully mechanical systems with heat recovery (MVHR) (see Fig. 1). These systems incorporate smart control mechanisms that utilize different IAQ sensors (CO2, VOC, RH), to adjust the airflow rate(s) locally or centrally to the detected needs. The IAQ sensors are located at the control valves or at the central unit, but not within the rooms.

Over time with thermal and energy regulations, buildings are increasingly insulated and airtight to control better the heat exchanges between the indoor and outdoor environments. The primary function of the mechanical ventilation system is to ensure healthy air by diluting odours and humidity with fresh air. However, in many situations, windows opening can be much more effective in terms of thermal comfort, air quality, or release heat loads due to a higher air change rate than the mechanical ventilation system itself.

In the frame of the project Flux50 smart ventilation, researchers and industrials aim at qualifying ventilation in mid-sized buildings through multidisciplinary consideration of sleep quality, user satisfaction, acoustic comfort, installation, maintenance, resilience and indoor air quality. As those factors may impact at different levels it is important to select a common metric for evaluation. Assessment of financial costs induced by the various categories will be used in that purpose.

Many studies have shown that the use of mixed-mode cooling can bring down the cooling load significantly while maintaining satisfactory in door air quality and thermal comfort. But there is little information available concerning mixed-mode cooling in China. Thus, basing on design parameters of design standard, A series of computer simulation of a typical mixed-cooling apartment in Guilin, lies south-west of China, was conducted by Eneryplus and Climate Consultant software.

This study is a first large-scale analysis of the performance of a cloud connected and smart residential mechanical extract ventilation (MEV) system based on field data. About 350 units were analysed over a period of 4 months from December 2018 up to March 2019, corresponding with the main winter period in Belgium. Half of the units were installed as a smartzone system which means additional mechanical extraction from habitable rooms as bedrooms. 

Advancing energy efficient renovation solutions in buildings necessitate adopting high-insulation and airtightness to avoid heat loss through transmission and infiltration, which can result in overheating. Elevated indoor temperatures have a highly negative effect on building occupants’ health, wellbeing and productivity. With the possibility of remote working, people spend more time at home, and therefore addressing the elevated indoor temperatures and the overheating risks in residential buildings proves to be essential.

Numerous studies have investigated the application of multi-zone demand-controlled ventilation for office buildings. However, although Swedish regulations allow ventilation rates in residential buildings to be decreased by 70 % during non-occupancy, this system is not very common in the sector. The main focus of the present study was to experimentally investigate the indoor air quality and energy consumption when using multi-zone demand-controlled ventilation in a residential building. The building studied was located in Borlänge, Sweden.

Net-zero energy building (NZEB) is thought to be the building of choice, but in practice, is also synonym  to high investment cost. It is, therefore, very important to investigate if the amount of the additional capital investment could be recouped from the energy saving (or generation). The investigation is particularly meaningful for industrial halls for the great energy saving potential (with respect to the high energy demand) and the ready energy generation possibility (due to favourable building geometry).