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Land, energy and water are the foundational resources of a country, and have a number of complex interactions with a changing climate. Their exploitation can have significant impacts on climate change, which in turn can affect the future availability of these resources. Thus it is important to properly manage these resources, to ensure that they can continue to provide long into the future. This thesis aims to assess the climate, land-use, energy and water systems (CLEWs) nexus in Bolivia, to determine critical points of interactions, and to produce recommendations for policy actions. This includes both mitigation and adaptation actions. The results show that Bolivia’s projected demand increases are certainly manageable, and with the investments as outlined, they can easily be satisfied, while reducing emissions and increasing climate resilience. An important result is that municipal and thermal water demand don’t appear to be limiting constraints, and so water management efforts should focus on agricultural and hydropower use. Recommended future work is to increase the scope and detail of the water and land model, so that all of the planned hydropower projects are included, and so that agriculture and irrigation demands and impacts can be more accurately predicted.

Sweden has a large multifamily housing stock that was built between 1960 and 1975. An important current issue is how this stock can be renovated in a sustainable way. The article analyses a strategy used by a suburban municipal housing company that had clear social ambitions and offered the tenants three options of renovation: Mini, Midi and Maxi. Most tenants chose the Mini alternative which meant that they could afford to stay and that there was no increase in costs for the social authorities. An investment analysis showed that the Mini alternative had a positive net present value, but that the Midi and Maxi alternatives were more profitable. Even though there was no clear environmental focus in the renovation, energy use was reduced by 8%. As a conclusion, the study shows that a sustainable renovation is possible but that there are a number of conflicts between the different dimensions of sustainability.

Sustainability is a normative concept, building on ideas such as justice, equity and responsibility, and based on human culture and society. Computers, internet, and the technologies that are central in our network society embed also normative values and are part of a cultural context. But the work looking at computer technologies and sustainability has been mostly oriented towards either calculating the impact of technology or using technology as a tool for solving practical problems. ICT is seen as a neutral system to be used or study, while the more normative aspects are mostly overlooked. This paper explores some of the problems arising from these overlooked normative values, such as focusing only on quantifiable problems while forgetting other aspects that may be as important but not easy to put in numbers, or trusting too much in numbers while hiding assumption and model choices. This paper suggests that more critical reflection on these questions is needed in the research area, as well as developing more connections with existing research on these topics in more traditional disciplines.

Minimizing thermal losses through windows and maintaining large glazing areas to provide adequate natural lighting in residential buildings are essential considerations for modern architecture, sus ...

As the building and construction industry contributes considerably to global warming there isa need to increase sustainable building, especially in developing countries where the conceptis often overlooked. Even though there is a need to implement more sustainable alternatives,research shows that it comes with many challenges. The aim for this study is therefore toanalyze the barriers and motivational drivers when implementing sustainable building inGhana. Chan et al. (2018) have previously conducted a categorization of the barriers forsustainable building through a quantitative study. This categorization was used as a guidingtool in this qualitative study, which was done through a Minor Field Study (MFS). Hence,eleven interviews with green champions were held on-site in Ghana. Further, to understand themotivation of the interviewees better, self-determination theory (SDT) was used to analyze thedata. The theory divides motivation into two different levels, extrinsic and intrinsic. The formeris a more controlled form of motivation, while the latter is more autonomous. The findingsshow that the most critical barriers were lack of professional knowledge and expertise, lack ofawareness of sustainable building and its benefits, together with higher costs. Despite thesebarriers, the green champions are still highly motivated. While intrinsic motivation is dominantamongst the green champions interviewed for this study, there is still a level of extrinsicmotivation at play. When comparing the barriers to the motivational factors one suggestion isfor the private and public sector to invest in demonstration projects. This would fulfill the greenchampions’ motivation to create their own identity for African architecture combined with anincreased awareness for sustainable building. This paper contributes with a unique andcomprehensive look at sustainable building in Ghana. Additionally, the study's theoreticalframework is not often used in the field of construction management, making this a valuablecontribution as the paper can be beneficial to leaders or managers in the construction industry. Bygg- och anläggningsindustrin bidrar avsevärt till den globala uppvärmningen vilket harskapat ett behov av att öka hållbart byggande, särskilt i låg- eller medelinkomstländer därkonceptet ofta förbises. Även om det finns ett behov av att implementera mer hållbara alternativvisar forskning att det kommer med många utmaningar. Syftet med denna studie är därför attanalysera barriärerna och drivkrafterna vid implementering av hållbart byggande i Ghana.Chan et al. (2018) har tidigare kategoriserat barriärerna för hållbart byggande genom enkvantitativ studie. Kategorisering har använts som ett vägledande ramverk i denna kvalitativastudie, som gjordes genom en fältstudie. Elva intervjuer genomfördes med aktörer definieradesom “green champions” på plats i Ghana. För att bättre förstå motivationen hos de intervjuade,applicerades självbestämmandeteorin (SBT) vid analysering av data. Teorin delar in motivationi två olika nivåer, extern och intern. Extern motivation är en mer kontrollerad form avmotivation, medan intern är mer autonom. Resultatet visar att de mest kritiska barriärerna ärbrist på professionell kunskap och expertis, bristande medvetenhet om hållbart byggande ochdess fördelar, samt högre kostnader. Trots dessa hinder är de intervjuade aktörerna motiverade.Även om intern motivation är dominerande bland de intervjuade, finns en nivå av externmotivation. Efter jämförelse mellan barriärerna och motivationsfaktorerna är ett förslag att denprivata och offentliga sektorn investerar i demonstrationsprojekt. Detta skulle uppfyllaaktörernas motivation att skapa sin egen identitet för afrikansk arkitektur kombinerat med enökad medvetenhet om hållbart byggande. Den här studien bidrar med ett unikt och heltäckandeperspektiv på hållbart byggande i Ghana. Dessutom är det unikt att använda studiens teoretiskaramverk inom området byggprojektledning, vilket gör detta till ett värdefullt bidrag eftersomuppsatsen kan vara till nytta för ledare eller chefer inom byggbranschen. 

This paper discusses adaptation and mitigation strategies as outlined in climate change scenarios. The adaptive perspective is closely connected to the concept of resilience understood as different ...

This paper presents results from a study on the impact of smart grid solutions, which includes development of a generic framework for power system analyses. The study has been performed as one of several independent studies, part of a national governmental task on smart grid in Sweden. A large amount of weather data, along with electricity consumption and wind power generation data, have been analyzed. Achieved results from these initial analyses can be used as reference material and have also been used within case studies presented. The proposed framework is flexible and numerous combinations of scenarios are possible to define. Integration of wind and solar power, analyses of transfer limits using static or dynamic rating and energy storage can be considered as well as weather effects. Results show how power systems can handle more electricity consumption and generation. The study shows that Smart Grid solutions are beneficial for resource efficient electricity grids. Moreover, different risk levels with respect to increased load can be included. Case study results show that energy storages most of the time will be unused, but that they can be used to increase the system reliability.

The societal goal of reaching net-zero CO2 emissions requires development of integrated biorefineries to produce biomass-derived fuels and chemicals. For sustainable second-generation bioethanol production, consolidated bioprocessing with the thermophile Clostridium thermocellum is regarded as a promising concept in view of the microorganism’s native ability to efficiently degrade plant cell wall material. However, for industrial implementation, improvements in ethanol titer and yield are needed. The aim of this thesis was to increase knowledge on the metabolism of C. thermocellum and thereby guide future metabolic engineering strategies to maximize the ethanol yield and titer. Yield improvements and fundamental studies into the metabolism of C. thermocellum would benefit from higher utilization of hexose monomers as well as minimized byproduct formation. To investigate underlying mechanisms for growth on glucose and fructose, laboratory evolution in chemostats together with genome sequence-based reverse engineering was applied. This successfully revealed two underlying mutations with (regulatory) roles in metabolism or transport of the monosaccharides. Together, these mutations enable reproducible and constitutive growth and are relevant for follow-up studies into transport and upper glycolysis. Separately, the mechanism behind the surprising byproduct formation of secreted amino acids was investigated by knock-out studies in NADPH-supplying and -consuming pathways. Physiological characterization in cellobiose- or ammonium-limited chemostats of mutant strains, with deletions in the NADPH-forming malate shunt or in the putatively ferredoxin-dependent ammonium assimilation, demonstrated a central role of NADPH in driving amino acid secretion. The findings indicated that electron availability will be crucial for further yield improvements in the NADH-dependent ethanol pathway. Fundamental mechanisms that might contribute to improved ethanol titer were addressed by studying thermodynamic and biophysical limitations. The pyrophosphate (PPi)-dependent glycolysis of C. thermocellum has been hypothesized to increase the overall ATP yield at the expense of the overall driving force. Knock-out studies combined with functional annotation of potential PPi-sources questioned this trade-off and increased knowledge of the PPi metabolism. The chaotropic effect (biophysical toxicity) of ethanol is commonly counteracted by lowering the cultivation temperature. Here, physiological characterization at varying ethanol titers demonstrated improved growth and fermentation at lower temperature. Comparisons to a non-ethanol producing mutant indicated both thermodynamic and biophysical limitations specifically in the ethanol pathway. Overall, these findings suggest that improvements in ethanol yield and titer would benefit from a simplified glycolysis that is engineered for a high driving force. While this work is beneficial for second-generation ethanol production, these findings can also be broadly applicable in the research and development of C. thermocellum as a cell factory for sustainable production of other fuels and chemicals. Samhällsmålet att nå nettonoll CO2 utsläpp kräver att integrerade bioraffinaderier utvecklas för att producera bränslen och kemikalier baserade på biomassa. För hållbar andra-generationens bioetanol-produktion betraktas konsoliderad bioprocessering med termofilen Clostridium thermocellum som ett lovande koncept, utifrån dess naturliga förmåga att effektivt bryta ner växtcellväggar. Emellertid krävs ökad titer och utbyte av etanol för att nå industriell implementering. Målet med denna avhandling var att öka kunskapen om C. thermocellums metabolism och därmed vägleda framtida strategier för att maximera utbytet och titern av etanol genom metabolic engineering. Förbättringar i utbytet samt fundamentala studier på metabolism hos C. thermocellum skulle gynnas av ett större utnyttjande av C6-mono-sackarider samt minskad produktion av biprodukter. Underliggande mekanismer för tillväxt på glukos och fruktos undersöktes med laboratory evolution i kemostater samt genomsekvensbaserad reverse engineering. I denna studie avslöjades två underliggande mutationer med (regulatoriska) roller i metabolismen eller transporten av dessa monosackarider. Tillsammans möjliggjorde dessa mutationer reproducerbar och konstitutiv tillväxt. Mutationerna är även relevanta för uppföljningsstudier av sockertransport och den övre glykolysen. Därutöver studerades den oväntade biproduktgruppen, aminosyror, genom knockoutstudier på NADPH-producerande och -konsumerande reaktionsvägar. Stammar med knockouts i den NADPH-producerande malatshunten eller i den potentiellt ferredoxin-kopplade ammoniumassimileringen karaktäriserades fysio-logiskt i cellobios- och ammoniumbegränsande kemostater. Detta visade att NADPH har en central roll i att driva aminosyrautsöndring. Dessa upptäckter indikerade att elektrontillgänglighet är kritiskt för att öka utbytet i den NADH-beroende etanolproduktionen. Fundamentala mekanismer som skulle kunna bidra till förbättrad titer av etanol studerades från termodynamiska och biofysiska perspektiv. En rådande hypotes har varit att den pyrofosfat (PPi)-beroende glykolysen hos C. thermocellum ökar ATP-utbytet på bekostnad av den totala termodynamiska drivkraften. Knockoutstudier kombinerat med funktionell annotering av potentiella PPi-källor ifrågasatte denna hypotes och ökade förståelsen av PPi metabolismen. Den kaotropiska effekten (biofysisk toxicitet) av etanol dämpas ofta i industriella processer genom att sänka odlingstemperaturen. Här demonstrerade fysiologisk karaktärisering vid olika etanoltiter att tillväxt och fermentering förbättras vid lägre temp-eraturer. En jämförelse mellan en modifierad icke-etanolproducerande stam och vildtypen indikerade att etanolproduktionen är begränsad av både termodynamiska och biofysiska faktorer. I helhet antyder dessa forskningsresultat att förbättringar i utbytet och titern av etanol skulle gynnas av en förenklad glykolys, konstruerad för att ge en hög termodynamisk drivkraft. Fastän denna avhandling fokuserar på andra-generationens etanolproduktion, kan dessa forskningsrön även appliceras mer brett i forskning och utveckling av C. thermocellum som en cellfabrik för hållbar produktion av andra bränslen och kemikalier. QC 2022-10-11