Energy saving and emissions reduction are both affectedby the energy efficiency of the built environment and the matching between the quality of the energy carrierand the quality of the required energy. To take into account qualitative aspects of energy leads to the introductionof the exergy concept. Heating and cooling of buildings require low valued energy, especially if low temperature heating systems and high temperature coolingsystems are used.

This paper shows the analysis of ventilation impact in the energy behaviour in rural areas. Considering that a large percentage of housing production is self-built in this part of Mexico, the impact of this construction activityis very important. This concerns the thermal comfort of the occupants of this type of constructions, which has also effects in the microclimate of the region.Due to the specifically local economy and the social structures, the self-built contributes in 60 % of the wholeof production of housings.

The purpose of this work is to study numerically the indoorenvironmental conditions in an office. The indoor air quality status has already been studied experimentallyunder different indoor and outdoor conditions and it was found that indoor originated pollutants concentrations(CO2, PM10 and total VOCs) were elevated when smoking was taking place and the windows were kept closed.

A numerical analysis of the natural ventilation in greenhouseswas performed at no-wind and low-wind speeds with the use of Computational Fluid Dynamics (CFD). Imposed boundary conditions correspond to the average measured experimental values during a ten days period.Numerical predictions of the ventilation efficiency and microclimate distribution of an arch type tunnel greenhouse, a typical Mediterranean-type greenhouse were obtained for various ventilator configurations.

Many modern office buildings have highly glazed facades.Their energy efficiency and indoor climate is, however, being questioned. Therefore more and more of these buildings are being built with double skin facades,which can provide improvements: a thermal bufferzone, energy savings, wind protection with open windows, fire protection, aesthetics, solar preheating of ventilation air, sound protection, nocturnal cooling and a site for incorporation of PV cells.

In hot and arid climates, evaporative cooling appears to have significant potential to provide thermal comfort and reduce the energy loads of summer season. These regions used wind towers as means to reduce energy consumption of air conditioning systems.However, the cooling potential of wind towers techniquewas investigated in real exiting building in Ouarglacity of Algeria (hot and arid climate); Measurements have been performed under two conditions with and without evaporative potential.A mathematical model of wind tower has been developed and validated using the measured data.

The Energy Performance of Buildings Directive (EPBD) obligates EU member states to develop a reliablemethodology capable of calculating and certifying the energy performance (EP) of their building stock. In this paper, studies on a series of school buildings, based on Standard prEN15217:2005, consider the impact that a lack of transparency in the data gathering procedure might have on the repeatability of the EP grades. The resultsshowed that variations in EP grades ranging from 0.06 to 1.06 EP grades were possible.

Global warming and fossil energy sources depletion represent an emergency at Planet scale. As a consequenceof the new regulations leading to lower energy demand in buildings for heating and cooling, new technologiessuch as ground source heat pump, are becomingmore and more popular in many parts of Europe,sometimes coupled with PV systems. Some solar thermal applications for heating (combi-systems) and cooling (solar assisted desiccant cooling systems) have also been developed in Europe and the interest in this area is growing.

The aim of the present study is to evaluate the design strategies for improving the summer thermal comfort conditions in a low-energy residential building located near Rome. The evaluated strategies include the natural air-flows through the windows: a) opening of windows for 24 hours and b) opening of windows during night hours only. The evaluations have been carried out by means of simulations using EnergyPlus building energy simulation programme.

The air distribution is a realizing form of indoor flow field, which plays a vital role to indoor air quality in the design of Heating,Ventilation and Air Conditioning. The average temperature and air speed in working area are closely related to air distribution, and the main factors that affect such two indices are the form, position, quantity of air outlet as well as the velocity, temperature of air supply. This article discusses the effect of air distribution on indoor air quality.