PR2009

The Energy Policy Act of 2005 (EPAct05) requires that federal building energy-efficiency performance standards be revised. New federal buildings must be designed to achieve energy consumption levels at least 30 percent below the levels established in the currently applicable version of standards published by the American Society of Heating, Refrigeration and Air-conditioning Engineers (ASHRAE) Standard 90.1 or the International Energy Conservation Code.

The current rate of consumption across Europe is leading to environmental problems. We need toreduce our impact to nature - our ecological footprint - by two thirds to achieve a sustainable andglobally equitable level. There is a strong need for more efficient and sustainable buildings. At present it is difficult to define the performance of buildings in an objective way to efficiency and sustainability. Goal of this project is to examine and to understand differences between different green building assessment rating systems approaches when applied to high performance buildings.

The indoor air quality is a very important issue and it generally depends on the airtightness of theshell, the ventilation rates, the deposition and the resuspension rates of the particles and the internalsources as well.The whole experimental procedure took place in a PASSYS test cell, which is located at the University Campus of Athens.

In Central and Northern Europe several thousands homes conform to the Passivhaus standard havebeen built. The applicability of this Standard has not yet been sufficiently tested in warmer climates,where reducing cooling needs under growing summer comfort requirements poses a challenge.The IEE Passive-on project has drafted a proposal to adapt the Standard to the conditions thatcharacterize Southern Europe.

Office buildings in central Chile normally show higher cooling than heating energy demand.Overheating is a frequent problem in this type of buildings in cities like Valparaso and Santiago.Santiago (33S) presents a Mediterranean climate, with a high thermal temperature oscillationbetween day and night throughout the year. Valparaso -with a temperate climate influenced by thePacific Ocean- shows lower temperature compared with Santiago.

Passive cooling of buildings is one of the energy-saving measures that can be employed in climateswith predominantly sensible cooling loads. There are several passive cooling techniques that can be used in buildings; among them night-time ventilation. Night-time ventilation cooling utilizes diurnalswing of outdoor temperature and it has been used in many buildings. However, this passive coolingtechnique only works well when a building has a sufficient thermal mass.

Differences might arise between the design and the real load of ventilation systems during operation.Consequently, the fresh air demand usually varies over a wide range. In normal usage, different types of gaseous contaminants enter the air that might be hazardous to health. The constant inhalation of contaminated indoor air might lead to discomfort or to harmful physiological effects.The difference between the design and the real load can be diminished by augmenting the ventilation system with appropriate components and controls.

The paper provides the results of monitoring on the specifics of indoor air quality in Latvian dwellingbuildings. It will present the results of the evaluation of the ventilation systems operation in differentworking regimes in Latvian climatic conditions.Until the end of 90-ties all dwelling buildings in Latvia were equipped with mandatory naturalventilation systems with stack effect.

The paper is devoted to the analysis of possibility for construction of low energy buildings withenvelopes controlled for minimization of energy consumption by air conditioning systems. It describes the possibilities to reduce energy consumption of large public buildings mainly in summer time when there are the highest electricity demands for cooling. The paper proposes constructive suggestion to create buildings whose walls, roofs and glassed surfaces have changeable thermal characteristics and methodology of control for separate elements.

The paper presents the results and analysis of the energy consumption of a newly designed office building in relation to quality of the indoor environment. The main energy consuming process in such a type of buildings is air-conditioning and cooling. The building was designed as a low-energy one, cooled by means of cooling ceilings. The architects and designers assumptions were checked by numerical simulation applying ESP-r software. Basing on the simulation results, the seasonal energy consumption was analyzed for different strategies of cooling.