Scientific Journal of Riga Technical University Architecture and Urban Planning
2010
Volume 4
Architectural Shaping Potential in Energy Efficiency Provision of Buildings Roberts Riekstiņš, Riga Technical University, Ivars Strautmanis, Riga Technical University Abstract – This publication pays attention on buildings’ energy efficiency aspect – opportunities for passive use of energy sources by means of architectural design. Built and experimental projects from around the world are identified and analysed by structuring the buildings’ according to typological classification. General attention is paid to the amplitude and topicality of the research issue, as well as the diversity, applied to the architectural techniques. Conclusion is made that building’s shape created in a smart way makes it possible to use substantial part of the renewable energy offered by nature. This subject is the basis for further research and application for Latvian climate conditions. Keywords – sustainable architecture, energy efficiency, eco-village, residential and public buildings, pilot projects of high-rise.
Global environmental problems, non-renewable (fossil) energy resources’ decline and rise in prices, as well as geopolitical tensions of countries in the world caused by energy management actualize the sustainable environmental development approach and strengthen the overall “green lifestyle” celebrity trends. Including also the ecological approach to the construction or “eco-construction”. The sustainability and energy efficiency are the cornerstones on which construction will be based in the future. “Sustainable development is ensured at all levels – from global to local and individual (think globally – act locally). It requires radical changes in thinking, life style, economic activity (economics), science and technology, spatial planning and living environment creation (architecture)” [1]. While the energy saving is one of the fundamental components of sustainable development ideology. “The actual energy balance statistics in Europe show that more than 40% of total energy consumption (even in other sources over 50%) are used by buildings, while two-thirds of it is consumed for heating! Buildings also create about 36% of total CO2 emissions” [2]! Therefore, the the political setting in European Union is for achieving substantial improvements in environmental sustainability, including about 5–6% reduction in overall energy consumption, increasing renewable energy share to 35%, as well as substantially reducing CO2 emissions by year of 2020. Construction areas are prepared for regulation of the directive, which will make substantial condition of buildings for energy efficiency in EU Member States, including the provision that, starting with the year 2020 all new buildings will have to be “zero-energy buildings” (to produce the same amount of energy as they consume). This decision will affect designers and builders also in Latvia. In many European countries, particularly Germany, Austria and the Scandinavian countries, the environmental principles
of building today are included in binding construction standards and become a mandatory part of the design process. There has been established a fixed energy efficiency scale of the buildings, which is fixed in energy consumption certificate and then creates the opportunity to receive public co-financing for building construction or reconstruction. I. Buildings’ shape effect on energy use
Energy efficiency of a building is simplify defined as the ratio between the internal climate of a building and the energy content required for the maintenance of this climate. Here it is important to note that energy efficiency does not only mean a reduction in energy consumption, as it is often assumed. It is important to ensure that the building’s energy consumption is provided from renewable sources! “Currently, general classification of the buildings is as follows: economic building (<80 kWh/m2), low-energy building (<40 kWh/m2), passive building (<15 kWh/m2)” [3] as well as zero-energy building producing the same energy as it consumes, and plus energy building producing more energy than it consumes. “Energy efficiency is expressed as the energy consumption characteristics of the heated space area (kWh/m2)”. Achievement of those criteria requires seeking for new directions in architecture, heating and engineering equipment of buildings. Latvian construction standards currently define parameters mainly for the building’s envelope, but the determining criterion will increase for a significant range. One will have to evaluate effectiveness of the entire building envelope construction insulation (building envelope – a term used in passive house design methodology) and tightness, efficient heating and cooling supply with heat recovery (recuperation), effective ventilation (in public buildings – including air
Fig. 1. Buildings’ shape design sketch.
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