monitoring

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.

In-situ performance of mechanical humidity-based mechanical exhaust ventilation (RH-MEV) is characterized in this study. This ventilation system includes fully-mechanical air inlets in the dry rooms and exhaust units in the wet rooms: the extensions and retractions of a hygroscopic fabric modify their cross-sections upon hygrometric changes in their environment without the need for motors or electronic sensors. 

The control of heat losses, inwards/out, in nearly zero energy buildings is of high importance. The transmission losses through the building envelope are easily reduced using larger amounts of insulation. Calculation of the impact of this action on the total energy demand of the building, is quite standard. It’s however much more difficult to determine the efficiency of actions to increase the airtightness of the building and the influence of the ventilation system.

MONICAIR --MONItoring & Control of Air quality in Individual Rooms-- is a pre-competitive field research project of a broad consortium of Dutch ventilation unit manufacturers and research institutes, supported by the Dutch government. The aim is to investigate the indoor air quality (IAQ) performance and energy characteristics of 9 different mechanical ventilation solutions in dwellings that meet strict air-tightness standards and comply with current building regulations.

Is Demand-controlled ventilation a relevant answer to face the new challenges of the Building sector, which requires everyday higher energy efficiency and better indoor air quality? Can Demand-controlled ventilation be considered as an alternative to heat recovery ventilation, through an affordable and low maintenance solution? Since the take off of the DCV in the early 80’s, these questions have been considered many times.

The present paper aims to explore the current energy performance of the existing housing stock of Greece while also examining the energy performance of buildings that have undergone refurbishment since the passing of the Energy Performance of Buildings Directive in 2010. A literature review of energy performance legislation and previous surveys are compared to data obtained from 400 dwellings with Energy Performance Certificates for the Thessaloniki and Naousa cities.

This paper reports a study of a unique system that integrates many renewable energy resources to achieve zero CO2 emission for building services for the head office of a company specialised in renewable energies. A dynamic thermal model was developed to simulate the summer cooling using both design criteria and recorded data. The monitored data acquired by the Building Management System (BMS) were also analysed with the predicted results to assess thermal performance of the system.

The thermo-hygrometric treatment related to the air change in buildings requires a relevant quota of the total energy demand for heating and air conditioning, especially when the ventilation exigency is significant. For this reason a correct energy saving strategy should always focus on the use of suitable techniques in order to reduce this consumption. For example, as the modern comfort science teaches, more flexible values can be accepted for the internal humidity set point without compromising indoor comfort conditions.

In this article, it will be shown how heat recovery ventilation with closed-loop ground heat exchange performs in practice, in a residential building in Nijeveen, The Netherlands. A state diagram is presented to explain when heat recovery and/or ground heat exchange is used during the year.

The monitoring of a demand controlled heat recovery ventilation system with ground heat exchange in a zero-energy building in Groenlo, The Netherlands, revealed interesting practical insights.