Monitoring and Data Analysis of two Low Energy Office Buildings with a Thermo-Active Building System (TABS)

A promising approach to reduce the primary energy demand of office-buildings without violatingthermal comfort is passive cooling by thermo-active building systems (TABS). The presented studyintroduces two low-energy office buildings within the framework of the German programme ENOBwhich are conditioned by TABS mainly supplied by geothermal energy.

Measuring Air Change Rates using the PFT Technique in Residential Buildings in Northern Portugal

Portugal has technical recommendations and standards regarding ventilation rates in naturalventilation systems.

Management Of The Time-Distribution Of The Needs For Indoor Air Renewal In Humidity Sensitive Ventilation

Although unanimously acknowledged by the experts for its performances as regards energyeffectiveness and indoor air quality optimisation, humidity sensitive ventilation still too often suffersfrom a lack of knowledge inherent in its singularities. The matter of this article is thus to bring a newlighting on the humidity sensitive ventilation determining airflow rates in the calculations of ductworksdimensioning and in the energy impact related to the air renewal.

Indoor Thermal Climate Criteria and the Effects on the Overall Environmental Performance of Air-Conditioning Systems

The cooling loads of an office building vary with the desired indoor thermal climate. However, there is a lack of knowledge on how significantly the various indoor climate criteria affect the overallenvironmental performance of the air-conditioning systems. Here, we analyze the environmentalconsequences of the energy use, as well as the possible modifications of the system design andcorresponding use of materials. The analysis is based on a theoretical case study of an airconditioning system designed for a typical office building situated in Sweden.

Indoor Air Quality and Thermal Environment of Elementary Schools in Winter

This study aims at investigating the actual conditions of indoor environment in schools in order toobtain fundamental information for proper ventilation design of buildings. Indoor environment of twonew elementary schools in Tohoku district of Japan was investigated for a week in the winter 2005.Temperature and humidity, concentrations of Carbon Dioxide (CO2), ventilation airflow rates,concentrations of chemical substances, and the opening condition of the windows and doors weremeasured in the three classrooms of each school.

Impact of Pump Control on Indoor Climate and Energy Efficiency of Hydronic Networks

The use of variable speed pump allows to save energy. Therefore, the impact of these technologieson the heating system and thermal comfort in buildings is rarely highlighted. The objective of this study is to show the possible impact of variable speed pump control on thermal comfort, energyconsumption and costs in buildings.The paper describes a method to evaluate the performance of a heating system in terms of thermalcomfort and global costs. A simulator has been implemented under Matlab/Simulink using theSIMBAD Toolbox to carry out annual simulations.

Experimental determination of thermal characteristics of lightweight building element with dual ventilated cavities

Available time for building construction is getting shorter, therefore the number of buildings which are built with lightweight building elements (LBE) is increasing. LBEs are elements of greater dimensions with low specific weight and low thermal transmittance. Their characteristic is also low thermal stability. By upgrading LBE with dual ventilated cavities (DVC) with counter flow becomes standard LBE a thermally activated building construction with increased thermal resistance and thermal stability. It enables using of solar radiation and heat recuperation from used air.

Exergy Analysis as an Assessment Tool of Heat Recovery of Dwelling Ventilation Systems

In cold and moderate climates, improvements in building shell insulation and air-tightness imply a shiftin heating loads from transmission and infiltration towards ventilation. Heat recovery from the ventilation airflow plays an increasingly important role in minimising energy needs. Such heat recovery systems rely on the input of electric power (to drive fans, heat pumps, etc.) in order to recover thermal energy. Since electricity input is relatively small compared to the amounts of thermal energy recovered, such systems are efficient from an energy viewpoint.

Energy-Environmental Efficiency in the Integrated Design of a School Building in Imola, Italy

The Municipality of Imola is strongly committed to environmental friendly and energy consciouspolicies both at urban planning level and public building design. In particular, the latest constructionplan of a new junior High School building has given a chance for checking an environmentally sound and energy conscious approach on the architectural and technological design development of an educational building.

Demand Controlled Ventilation. A Detailed Study of Energy Usage by Simulation

Detailed mathematical models of VAV equipment and subsystems have been developed and used tocompose larger DCV systems with a large degree of detail. The models and systems take intoaccount both flow/pressure distribution and thermal/contaminant dynamics. The models have beenvalidated against measurements. A number of detailed simulation cases have been conducted. Theresults show that energy usage depends strongly depends on occupancy, flow rates, chosen setpoints as well as the outdoor temperature.