Building design strategy for cold climate using passive design and renewable technologies
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This thesis presents an analysis of various measures and technologies leading to establishing a strategy to achieve energy efficiency in buildings, particularly in the context of Kazakhstan. The developed strategies can be implemented in other countries with similar background and climate conditions. In countries with cold climate such as Norway and Kazakhstan, people spend over 90% of their time indoors, which means that they rely heavily on electricity, heating, and ventilation. Meeting these needs requires a substantial amount of energy and this, in turn, is the cause of a considerable amount of emissions and waste entering the environment. The building sector that is responsible for 40% of global energy demand is one of the greatest consumers of energy. At the same time, buildings are responsible for almost 50% of the CO2 emissions. Among other types of buildings, the impact of residential sector is significant due to its high share in the building stock of these countries. To address these challenges, the residential building industry has to adopt multidisciplinary sustainability and renewable energy practices. Making buildings energy efficient is believed to be an effective way to address challenges of both energy consumption and environmental impact of buildings. To design, construct and manage an energy-efficient building, a wide range of measures and strategies are currently applied. Among them are passive design principles and integration of renewable energy technologies. While for example, Norwegian residential construction has significantly advanced in this field through the adoption of various technical regulations and up-to-date sustainability measures, it still requires further advancements to meet ever stricter energy performance requirements. Unlike in Norway, Kazakhstan’s residential energy efficiency is still behind. While being the global leader in terms of carbon dioxide emissions per capita, Kazakhstan is facing significant energy increase in demand due to an ongoing construction boom, considerable energy losses of aging building stock, and poor energy efficiency practices. The root causes of poor sustainability level, among others, are related to a lack of targeted innovations, respective policies and regulations, guidelines, methodologies, practical examples, technologies, and low level of awareness among general public and the construction industry. Thus this thesis aims to develop a new “system approach” to advance energy efficiency of residential buildings in Kazakhstan. The integrative approach, which is considered novel, analyzes the concept of energy efficient buildings from different perspectives and using different methods. It is found, that system approach concentrating on incremental component efficiency can lead to improved results, and may lead to further small, incremental improvements; a complex holistic system approach can lead to more significant building energy efficiency. Many researchers have proposed adopting such an approach and have presented promising results. However, with the increasingly complex world today where technologies and sustainability practices are rapidly advancing and the effects of climate change and resources scarcity (particularly energy) are becoming more pressing, the science behind energy-efficiency in buildings should continuously seek for more advanced ways of integrating a wide range of solutions. This thesis attempted to emphasize the role of not only technical solutions as engineering would usually require but also the importance of advanced design solutions, renewable energy, policy-based support as well as concentrating on the role of people. This approach is unique for Kazakhstan where construction engineering is considered as a purely technical sphere. Treating building sector in silos is no longer effective. Since the challenge of climate change and energy scarcity is a complex issue, the solutions should also be complex and system-based. The proposed system approach involves a synergy of methodologies addressing different facets of building energy efficiency in the context of cold climate conditions. Numerical simulation method was used to develop a calibrated computer model for predicting the impact of various design and operational parameters on overall energy performance of a detached passive house in Trondheim (Norway). Another model was developed to investigate energy performance of a multi-story residential building in Astana (Kazakhstan) with respect to its orientation validated by separate thermal calculations based on the local and international standards and codes. The thesis also includes literature survey of renewable energy technologies to develop up-to-date expertise on renewable energy integration into contemporary buildings. Computational fluid dynamics (CFD) tools were used to demonstrate the effect of important aspects of passive design, such as building orientation, configuration, and envelope on energy efficiency and external (wind) comfort. The thesis additionally focuses on the socio-technical assessment of building energy performance after building façade (envelope) reconstruction using CFD analysis and survey among occupants, builders, and the general public. The impact of the user behavior on implementation and performance of various energy efficiency measures was assessed by carrying out post-occupancy surveys that also include personal interviews, therefore, allowing the evaluation of the impact of different efficiency measures on post occupancy comfort level from the real data in both countries. Technical standards and buildings codes with regard to building energy efficiency are reviewed to make recommendations that can be adopted in Kazakhstan at short and medium term basis so that a smooth transition can be made in the country’s building industry to achieve energy efficiency.