Buildings can play an essential role in the transition to a sustainable society. Different strategies, including improved energy efficiency in buildings, substitution of carbon intensive materials and fuels, efficient energy supply among others can be employed for this purpose. In this thesis, the implications of different insulation materials, modelling and design strategies on primary energy use of residential buildings are studied using life cycle and system perspective. Specifically, the effects of different insulation materials on production primary energy and CO2 emission of buildings with different energy performance are analysed. The results show that application of extra insulation materials to building envelope components reduces the operating primary energy use but more primary energy is required for the insulation material production. This also slightly increases the CO2 emissions from material production. The increases in primary energy use and CO2 emissions are mainly due to the variations in the quantities, types and manufacturing processes of the insulation materials. Thus, choice of renewable based materials with energy efficient manufacturing is important to reduce primary energy use and GHG emissions for building material production. Uncertainties related to building modelling input parameters and assumptions and how they influence energy balance calculations of residential buildings are explored. The implications on energy savings of different energy efficiency measures are also studied. The results show that input data and assumptions used for energy balance simulations of buildings vary widely in the Swedish context giving significant differences in calculated energy demand for buildings. Among the considered parameters, indoor air temperature, internal heat gains and efficiency of ventilation heat recovery (VHR) have significant impacts on the simulated building energy performance as well as on the energy efficiency measures. The impact of parameter interactions on calculated space heating of buildings is rather small but increases with more parameter combinations and more energy efficient buildings. Detailed energy characterisation of household equipment and technical installations used in a building is essential to accurately calculate the energy demand, particularly for a low energy building. The design and construction of new buildings present many possibilities to minimise both heating and cooling demands over the lifecycle of buildings, and also in the context of climate change. Various design strategies and measures are analysed for buildings with different energy performance under different climate scenarios. These include household equipment and technical installations based on best available technology, bypassing the VHR unit, solar shading of windows, combinations of window u- and g-values, different proportions of glazed window areas and façade orientations and mechanical cooling. The results show that space heating and cooling demands vary significantly with the energy performance of buildings as well as climate scenarios. Space heating demand decreases while space cooling demand and the risk of overheating increase considerably with warmer climate. The space cooling demand and overheating risk are more significant for buildings with higher energy performance. Significant reductions are achieved in the operation final energy demands and overheating is avoided or greatly reduced when different design strategies and measures are implemented cumulatively under different climate change scenarios. The primary energy efficiency of heat supply systems depends on the heat production technology and type of fuel use. Analysis of the interaction between different design strategies and heat supply options shows that the combination of design strategies giving the lowest primary energy use for space heating and cooling varies between heat supply from district heating with combined heat and power (CHP) and heat only boilers (HOB). The primary energy use for space heating is significantly lower when the heat supply is from CHP rather than HOB. Operation primary energy use is significantly reduced with slight increase in production primary energy when the design strategies are implemented. The results suggest that significant primary energy reductions are achievable under climate change, if new buildings are designed with appropriate strategies.

Global warming is one of the biggest challenges of our society. The road transport sector is responsible for a big share of Greenhouse Gas (GHG) emissions, which are considered to be the dominant cause of global warming. Although most of those emissions are associated with traffic operation, road infrastructure should not be ignored, as it involves high consumption of energy and materials during a long lifetime. The aim of my research was to contribute to improved road infrastructure planning by developing methods and models to include a life cycle perspective. In order to reach the aim, GHG emissions and energy use at different life cycle stages of road infrastructure were assessed in three case studies using Life Cycle Assessment (LCA). These case studies were also used for development of methodology for LCA of road infrastructure. I have also investigated the coupling of LCA with Geographic Information Systems (GIS) and the possibility to integrate LCA into Environmental Impact Assessment (EIA) and Strategic Environmental Assessment (SEA). The results of the first case study indicated that operation of the tunnel (mainly, lighting and ventilation) has the largest contribution in terms of energy use and GHG emissions throughout its life cycle. The second case study identified the main hotspots and compared two methods for asphalt recycling and asphalt reuse. The results of the third case study indicated that due to the dominant contribution of traffic to the total impact of the road transport system, the difference in road length plays a major role in choice of road alternatives during early planning of road infrastructure. However, infrastructure should not be neglected, especially in the case of similar lengths of road alternatives, for roads with low volumes of traffic or when they include bridges or tunnels. This thesis contributed in terms of foreground and background data collection for further LCA studies of road infrastructure. Preliminary Bill of Quantities (BOQ) was identified and used as a source for site-specific data collection. A new approach was developed and tested for using geological data in a GIS environment as a data source on earthworks for LCA. Moreover, this thesis demonstrated three possible ways for integrating LCA in early stages of road infrastructure planning. / <p>QC 20160329</p>

An environmentally-based systems approach to sustainability analyses of organic fruit production systems in New Zealand. This research introduces an approach for the assessment of the sustainability of farming systems. It is based on the premises that sustainability has an environmental bottom line and that there is very limited substitutability between natural capital and other forms of capital. Sustainability assessment is undertaken through analyses of energy and material flows of the system and their impacts on the environment. The proposed sustainability assessment approach is based on two high level criteria for sustainability: efficient use of energy and non-degradation of the environment from energy and material use. Sustainability assessment of organic orchard systems in New Zealand was undertaken to demonstrate this approach. Five indicators which address the two criteria for the sustainability of the orchard systems are the energy ratio, the CO2 ratio, changes in the soil carbon level, nutrient balances, and the leaching of nitrogen. Organic kiwifruit and organic apple systems are modelled based on their key energy and material flows and their interactions with the natural environment. The energy and material flows are converted into appropriate energy and matter equivalents based on coefficients taken from the published literature. Sustainability indicators are estimated over one growing season using two computer modelling tools, Overseer® and Stella®, in a life cycle approach. Sustainability assessment of the organic orchard systems suggests that the approach is useful for evaluating energy use and key environmental impacts that occur in soil, water and atmosphere. The results indicate that the model organic orchard systems are sustainable in terms of energy use and are a net sink of CO2-equivalent emissions. The implication of this result is that organic orchard systems potentially could trade carbon credits under the Kyoto Protocol. The findings also suggest that the sustainability assessment approach is capable of identifying the trade-offs within the sustainability indicators associated with particular management practices. Further research to improve and validate the proposed approach is essential, before it can be practically used for decision making at the orchard level and for policy making at the national level.

Forest fuels can be recovered, stored and handled in several ways and these different ways have different implications for CO2 emissions. In this thesis, comparative analyses were made on different forest-fuel systems. The analyses focused on the recovery and transport systems. Costs, primary energy use, CO2 emissions, storage losses and work environment associated with the use of forest fuel for energy were examined by using systems analysis methodology in a life cycle perspective. The bundle system showed less dry-matter losses and lower costs than the chip system. The difference was mainly due to more efficient forwarding, hauling and large-scale chipping. The potential of allergic reactions by workers did not differ significantly between the systems. In difficult terrain types, the loose material and roadside bundling systems become as economical as the clearcut bundle system. The stump and small roundwood systems showed the greatest increase in costs when the availability of forest fuel decreased. Stumps required the greatest increase in primary energy use. Forest fuels are a limited resource. A key factor is the amount of biomass recovered per hectare. Combined recovery of logging residues, stumps and small roundwood from thinnings from the same forest area give a high potential of reduced net CO2 emissions per hectare of forest land. Compensation fertilization becomes more cost-effective and the primary energy use for ash spreading becomes low – about 0,25‰. The total amount of available forest fuel in Sweden is 66 TWh per year. This would cost 1 billion €2007 to recover and would avoid 6.9 Mtonne carbon if fossil coal were replaced. In southern Sweden almost all forest fuel is obtainable in high-concentration areas where it is easy to recover. When determining potential CO2 emissions avoidance, the transportation distance was found to be less important than the other factors considered in this work. The type of transportation system did not have a significant influence over the CO2 avoided per hectare of forest land. The most important factor analysed here was the type of fossil fuel (coal, oil or natural gas) replaced together with the net amount of biomass recovered per hectare of forest land. Large-scale, long-distance transportation of biofuels from central Sweden has the potential to be cost-effective and also attractive in terms of CO2 emissions. A bundle recovery system meant that more biomass per hectare could be delivered to end-users than a pellet system due to conversion losses when producing pellets.

Being located in subtropical area, the weather in Taiwan is constantly hot and humid which imposes huge cooling load on buildings. Especially, the economic booms in Taiwan further boosted power demand, and worsened the power shortage situation. Dr. H.T. Lin and Dr. K.H. Yang had conducted systematic research since mid-1980s, which constructed a solid ground in this field in Taiwan. Among these results, the ENVLOAD index has become legal binding since 1997 while the PACS index is now under investigation. However, it is in short of analysis and full-scale experimental investigation on energy use of hotels in Taiwan. Therefore, the establishment of the EUI and DUI indexes in Taiwan is the goal of this study. A simplified calculation method has been established in analyzing the energy use and demand use of hotels in Taiwan, by normalizing experimental data from full-scale tests. The result can be drawn accurately based on a few terms, which are available from daily building operations such as occupancy, and is thus practically straightforward and easy to use. In addition, the accuracy was validated by experiments performed and data collected through information technology with Internet access in 4 different forms, which yielded successful results. It is anticipated that the calculation methodology developed in this study on EUI and DUI, and the experimental validation would provide a foundation for the establishment of hotel building energy codes in Taiwan in the future.

Energy use is a part of everyday life and the use of energy is a part of the global climate change. Policy makers urge individuals to change their daily behaviour in order to mitigate climate change and care for our common environment. The dissertation regards daily behaviour as activities performed by individuals. The theoretical base is the time-geographic approach wherein everyday life is regarded as a sequence of interlinked activities performed by indivisible individuals. The dissertation investigates individuals’ energy use as an outcome of the activities they perform in everyday life. The empirical base of the dissertation is time-diaries from the Swedish time use survey 2010/2011. The diary data is explored as sequences of daily activities by using sequence analysis and clustering. The results show that individuals’ energy use is closely interweaved with how they live their everyday lives in terms of activity sequences. The results imply that changing an activity affects both the intricate web of interaction in the household and the interdependence of activities in everyday life. Change does not only affect the singular activity that was the object for the change, but rather major parts of the sequence of activities. In order to address energy conservation in information campaigns considerations ought to be taken on how everyday life is shaped and formed by the individual, by negotiations between the individuals in households, and societal structures. Information can be targeted to groups of individuals  with similar activity sequences as they are revealed by cluster analysis. / Energianvändningen är en del av vardagen likaväl som användningen av energi är en del av den globala klimatförändringen. För att mildra effekterna på vår gemensamma miljö uppmanas människor av politiker och andra beslutsfattare att förändra sitt vardagsbeteende. I avhandlingen betraktas vardagsbeteendet som människors dagliga aktiviteter. Avhandlingens teoretiska grund är den tidsgeografiska ansatsen, där människors vardag betraktas som en sekvens av de aktiviteter som utförs av odelbara individer. Människors dagliga sekvens av aktiviteter undersöks för att ta reda på vilken energianvändning som genomförandet av aktiviteterna ger upphov till. Den empiriska grunden för avhandlingen är tidsdagboksdata från den svenska tidsanvändningsstudien från 2010/2011 och avhandlingen utforskar tidsdagböckerna som sekvenser av aktiviteter med hjälp av sekvens- och klusteranalys. Resultaten visar att individers energianvändning är nära sammanvävd med de aktivitetssekvenser som visar hur vardagslivet levs. Resultaten pekar vidare på att förändringar av enskilda aktiviteter också påverkar andra aktiviteter i det dagliga livet. Förändringar av en aktivitet påverkar således hela den dagliga sekvensen av aktiviteter. I utformningen av information som syftar till att minska hushållens energianvändning bör hänsyn tas till hur vardagslivets aktivitetssekvens formas av den enskilde i samspelet både med andra individer i hushållet och med samhällsstrukturerna. Målgruppsinriktad information kan utformas med utgångspunkt from människors likartade aktivitetsmönster så som de framgår genom klusteranalys.

Due to the requirement for economic sustainability, studies on the use of biomass or biofuels to energy obtention has increased in recent years. Biomass energy is obtained by burning wood, bagasse, forest and agricultural residues, among others. Nowadays, renewable resources represent about 20% of total energy supply in the world and biomass is about 14%. The production of electricity from biomass is currently advocated as very important alternative for developing countries. The present work aims to study species adaptable to northeastern of Brazil for energy generation. In this context, Cnidoscolus quercifolius (faveleira) and Annona muricata L. (graviola), are characterized as raw materials with potential use for alternative energy source. Besides the possibility of evaluating the various parts of the plant for power generation, it is possible to employ the seeds, due their high content of oil which can be used as a source of triacylglycerols for the biodiesel production. / Devido à busca pela sustentabilidade econômica, estudos sobre obtenção de energia através do uso direto biomassa ou de biocombustíveis, tem aumentando nos últimos anos. A energia da biomassa é obtida através da combustão de lenha, bagaço de cana, resíduos florestais, resíduos agrícola, entre outros. Já a energia proveniente do biodiesel é obtida através de sua síntese a partir de fontes vegetais ou seu uso como combustível líquido. Dessa forma a energia gerada é renovável. Hoje os recursos renováveis apresentam cerca de 20% de suprimento total de energia no mundo, sendo que só de biomassa seria da ordem de 14%. A produção de energia elétrica a partir da biomassa, atualmente, é muito defendida como importante alternativa para países em desenvolvimento. O presente trabalho tem como objetivo estudar espécies adaptáveis ao nordeste brasileiro para geração de energia. Nesse contexto, cnidoscolus quercifolius Pax et K. Hoffm (faveleira) e annona muricata L. (graviola), se caracterizam como matérias-primas com potencial uso para fonte alternativa de energia. Além da possibilidade de avaliação das várias partes da planta na geração de energia, existe a possibilidade de empregar as sementes. As mesmas contêm alto teor de óleo que pode ser empregado como fonte de triacilgliceróis para a produção de biodiesel e a torta, resultante da extração, pode ser igualmente avaliada como resíduo de biomassa.

Fossil oil is the major source of energy and pre salt deposits were discovered recently. Besides that, this source is not renewable and one possible substitute is the energy from biomass. In this context, one of the biggest challenges is to develop energy matrices from alternative sources of low cost, making them economically competitive. Among the various alternatives, we highlight the use of biomass residues for energy generation by burning. This work aims to make the study of the species of palm native to northeastern Brazil, Syagrus coronate (Martius) Beccari as a potential use as an alternative energy source. When evaluating the quality of the parts of ouricuri, with and without compactation, for energy use and subsequent extraction and characterization of oil and biodiesel production is possible to observe a potential as an alternative energy source. Several parts of ouricuri samples presented to the calorific values around 17,000 J, and its calorific value is compared to biomass such as sugarcane bagasse and corn stover (which are widely used in the state of Alagoas).The biodiesel ethylic and methylic produced,from the oil of Ouricuri, in the presence of basic catalyst, are according to National Agency of Petroleum, Natural Gas and Biofuels specifications, considering the results of viscosity at 40 ºC, density to 20ºC, residue carbon, calorific power and cold filter plugging point. / Conselho Nacional de Desenvolvimento Científico e Tecnológico / reservas ultraprofundas (pré-sal), porém sendo não renovável tem a possibilidade de se esgotar e, uma das energias que se torna possível substituta é a energia proveniente da biomassa. Nesse contexto, um dos maiores desafios é desenvolver matrizes energéticas a partir de fontes alternativas de baixo custo, tornando-as competitivas economicamente. Entre as diversas alternativas, destaca-se a utilização de resíduos de biomassa para geração de energia através da queima. O presente trabalho tem como objetivo realizar o estudo com a espécie de palmeira nativa no Nordeste brasileiro, Syagrus coronata (Martius) Beccari como potencial uso como fonte alternativa de energia. Ao avaliar a qualidade das partes do ouricuri, com e sem compactação, para fins energéticos e posterior obtenção e caracterização do óleo (obtido a partir da amêndoa), azeite (obtido a partir da polpa) e biodiesel (obtido a partir da amêndoa) observa-se sua potencialidade como fonte alternativa de energia. O endocarpo, as folhas e o epicarpo do ouricuri apresentaram valores para o poder calorífico em torno de 17.000 J, e seu poder calorífico é comparável a biomassas como bagaço de cana e palha de milho (que são muito utilizadas no estado de Alagoas). Os biodieseis etílico e metílico produzidos, a partir do óleo de Ouricuri, via catálise básica, apresentaram-se de acordo com as especificações da Agência Nacional de Petróleo, para os parâmetros de viscosidade a 40ºC, densidade a 20ºC, resíduo de carbono, poder calorífico e entupimento de filtro a frio.

This study incorporates the potential use of Variable Frequency Drives on various motors as well as areas of improved heat transfer in an older, mid-sized coal fired power plant. In power plants, fluid flow rates are often controlled using dampers or valves while the motors that power the pumps stay at full speed resulting in a significant amount of wasted electrical power; energy is also lost due to poor heat recovery prior to gases leaving the system. By examining pump usage as well as additional heat available for recovery, potential energy savings will be determined. Preliminary results of five motors suggested for variable frequency drive application show annual savings that total 31.1 GWh, resulting in a 1.66% increase in overall plant efficiency. Total project costs are near $2 million resulting in a simple payback period of less than two years assuming 0.04 $/kWh. For every degree reduction of the flue gas temperature by means of heat recovery that is reused elsewhere in the cycle, 2 Billion BTU of coal would be saved annually. One realistic scenario suggested heat recovery resulting in a 120°F degree reduction of flue gas temperature amounting to a 2.54% increase in cycle efficiency.

Senast år 2045 ska utsläpp av växthusgaser reduceras till en nollnivå enligt Sveriges riksdag. I Sverige står bostads- och servicesektorn för 40 % av den sammanlagda energiförbrukningen. Studien baseras på en energianalys av ett flerbostadshus beläget i Ronneby, av typen trygghetsboende vilket leder till en unik boendesituation i byggnaden. Byggnaden förbrukar cirka 25 % mer energi än den beräknade samt avtalade energiförbrukningen. Syftet är att i framtida projekt kunna få energiberäkningar att stämma bättre överens med verklig specifik energiförbrukning. Studien bygger på energisimuleringar, termografering samt undersökningar av vädringsvanor. Simuleringarna som är baserade på den verkliga datan, visar en förväntad energiförbrukning i liknande storleksordning som den uppmätta förbrukningen. Skillnaden mellan resultaten i studiens olika beräkningar beror på den unika boendesituationen i byggnaden, indatan för installationer samt byggnadens klimatskal. Studien påvisar att aktuella boendesituationer i byggnader och hur byggnader nyttjas påverkar den specifika energiförbrukningen i stor grad. / After 2045, greenhouse gases should be reduced to a zero level according to the Swedish parliament. Energy use in Sweden from residential and service sector is 40 % of the country´s total energy use. The study is based on an energy analysis of a multi-family building in Ronneby. The building is a trygghetsboende, which means unique living conditions for the residens. Actual energy use in the building is about 25 % higher than projected energy use. The main purpose of the study is to make energy calculations to match better with real specific energy use. The study is based on energy simulations, thermography and interviews of residents´ airing habits. Results from the simulations based on actual data, show an expected energy use similar to the measured values. Differences between the simulations depend on the unique conditions in the building, input data for ventilation and the building envelope elements. The conclusion is that living habits of residents in buildings have a decisive role in the buildings energy use.