Breakthrough of natural and hybrid ventilative cooling technologies: models and simulations

This special issue on Breakthrough of natural and hybrid ventilative cooling technologies: models and simulations, together with the connected issue Breakthrough of natural and hybrid ventilative cooling technologies: strategies, applications and case studies (vol. 16, issue 1), focuses on methods, tools and technologies for reaching the above-mentioned goal through the use of ventilative cooling, i.e. cooling by controlled natural ventilation (CNV). This strategy is one of the most cost-effective alternatives to air-conditioning systems.

Analysis of convective heat transfer coefficient correlations for ventilative cooling based on reduced-scale measurements

Ventilative cooling can be used as a passive cooling measure to reduce the cooling energy demand of buildings. It can be used during the day, directly removing excessive heat gains, or during the night (i.e. night flush), in which cold outdoor air flows through the building and cools down the indoor air volume and subsequently the thermal mass of the building. Night flushing reduces the indoor air temperatures at the beginning of the next day and the cooling demand over the day.

Better implementation of ventilative cooling (cooling of buildings using outside air as main source) in national building standards, legislation and compliance tools

Low energy buildings are highly insulated and airtight and therefore subject to overheating risks, where Ventilative cooling (VC) might be a relevant solution. VC is an application (distribution in time and space) of air flow rates to reduce cooling loads in spaces using outside air driven by natural, mechanical or hybrid ventilation strategies. Ventilative cooling reduces overheating in both existing and new buildings - being both a sustainable and energy efficient solution to improve indoor thermal comfort (State-of-the-art-review, Kolokotroni et al., 2015).

Ventilative Cooling – Time for large scale implementation?

The current development in building energy efficiency towards nearly-zero energy buildings (nZEB) represents a number of new challenges to design and construction. One of the major new challenges is the increased need for cooling arising in these highly insulated and airtight buildings. The cooling demand depends less on the outdoor temperature, and more on solar radiation and internal heat gains. This naturally gives better potential for the use of ventilative cooling technologies, because the cooling need is not only in summer, but actually all year round. 

26 March 2020, Webinar: “Ventilative Cooling – design and examples”

Venticool, EBC Annex 62 "Ventilative Cooling", and the Air Infiltration and Ventilation Centre are organizing the webinar “Ventilative Cooling – design and examples” to be held on Thursday 26th March 2020 at 15:00-16:30 (CET). This webinar will present the main outcomes of IEA EBC Annex 62 on ventilative cooling design as well as give examples of applications and lessons learned.

Presentations & Speakers:


Ventilative cooling effectiveness in office buildings: a parametrical simulation

Controlled Natural Ventilation (CNV) is one of the potential most effective passive cooling technique to reduce cooling needs of buildings in temperate-hot climate zones. However, a correct balance amid internal heat capacity, thermal insulation, and net opening area is important to achieve optimal results. The present paper shows results from an original simulation process carried out within the Course “ICT in building design” of the Master degree programme ICT4SS (ICT for smart societies) at the Politecnico di Torino.

Energy analysis for balanced ventilation units from field studies

Balanced ventilation units are well known to provide a sufficient amount of fresh air in residential buildings in a controlled way, without relying on ever-changing naturally driven forces. During colder periods, heat recovery ensures a reduction of the ventilation heating load. Outside the colder periods, recovery is reduced or shut off automatically, providing mechanical ventilative cooling. During warmer periods, the recovery is used again to provide a comfortably cool supply of fresh air.

Ventilative cooling - IEA TCP EBC annex 62


Freevent : ventilative cooling and summer comfort in 9 buildings in France

Recent studies have shown that ventilative cooling reduces overheating, improves summer comfort and decreases cooling loads. Therefore, it is considered as one of the most efficient way to improve summer comfort. Although, HVAC designers still lack of guidelines to improve the energy and comfort efficiency of their installations.  

Ventilative cooling in a school building: evaluation of the measured performances

The test lecture rooms of KU Leuven Ghent Technology Campus are one the demonstration cases of IEA EBC Annex 62: Ventilative Cooling. This nZEB school building is realised on top of an existing university building and contains 2 large lecture rooms for maximum 80 students with a floor area of 140m² each. An all air system with balanced mechanical ventilation is installed for ventilation, heating and cooling.