The worldwide fast growth of the transportation sector contributes to a large andgrowing share of global greenhouse gas (GHG) emissions. The Swedish TransportAdministration report indicates that emissions from domestic transport increasedin 2018. Having an idea that the workplace parking lots have the potential toincrease the share of renewable energy production in Sweden, an investigation forthe solar-powered electric vehicle (EV) charging station is conducted. This studyaims to clarify the knowledge on what the potentials are, financial assessment, andassessment of the photovoltaic (PV) self-consumption of EV charging in theworkplace charging station. Without knowledge about the highlighted parameters,investors may hesitate to invest in a PV project such as a solar-powered EV chargingstation system. To achieve the objective of this thesis, appropriate tools and/orsoftware are used. PV*SOL software tool is used for simulation and analysis ofenergy system efficiency with EV charging station integrated for different PVsystems deployed in the same location of Sweden. This software tool allows thedesign and calculations of the PV system and EV charging station integrated.Currently registered cars in Sweden indicate that EVs are dominating and will keepthe pulse in the future. This domination will enforce more need for electricity, callfor renewable energy use, and promising significant GHG emissions reduction –sustainable environment. The study has proven that there is no immense insolationin Sweden, thus, the power converter can be undersized up to 30 % with respect tothe PV array to reduced energy loss. A feasible solar-powered EV charging stationrequires several factors such as initial investment (EV charging station, PV module,inverter, transport and installation, operation, and maintenance, etc.), andelectricity trading rate. The study of five PV system cases showed that the increasein size significantly increases the self-sufficiency ratio while self-consumption ratiodecreases. By increasing the PV array, both levelized cost of electricity and paybackperiod were considerably decreased as was intended. However, the more PV arrayincreased in size the more initial investment is required. Study on GHG emissionsof the solar-powered EV charging station as well as the deployment of local energystorage and EV smart charging are recommended as future works.

Quenching technique is widely used in industrial applications as it enhances the mechanical properties of metals such as hardness and tensile strength. This technique consists of a heating process followed by fast cooling which results in different microstructures that enhance the metal behavior. Current competitive market in metal field requires the implementation of advanced and optimizing techniques by means of efficient and sustainable quenching techniques. Furthermore, cooling by multiple array of water jets offers wide range of cooling rate control and consequently the achievement of the desired properties. Quenching cooling rate for a rotary cylinder by multiple impinging jets is investigated in this experimental study. A rotating steel cylinder is heated up to 700°C by an induction heater and cooled down in short time by an array of water impinging jets in order to study quenching process of the test specimen by the impinging jet technique. This fast cooling has been found to be a crucial parameter that enhances the characteristics of steel thoroughly. The magnitude of its influence has been previously studied in water pools cooling techniques. Consequently, a further understanding of quenching technique is aimed in this study by the variation of different parameters: the multiple jet’s pattern (inline and staggered), jet-to-jet spacing (S/d=4 and 6), rotational speed (10-70rpm) and water subcooling temperature (55-85K) that have been studied in 10 experiments. Running of the experiments have been done with the help of different programs such as LabVIEW and NiMAX. Measurements of the temperature along the cylinder has been carried out by using some embedded thermocouples that have been connected to the DAQ.  Results from the study revealed faster cooling with rotation speed 30rpm since the contact between hot surface and impinged water jet is improved for lower speeds. However, rotation speed10rpm results experienced negative effects. In addition, jet-to-jet spacing S/d = 4 caused higher cooling rate than S/d = 6 since the impinged water from neighbor jets lead to higher interaction between water fronts and consequently a more uniform cooling. Furthermore, significant differences have been found in temperature drop between points located closer to the center of the cylinder and the ones beneath the cooling surface. Regarding the multiple array configuration of nozzles, staggered configuration revealed more uniform cooling over the surface due to the fact that placement of the jets led to a better distribution of the impinged water in the measurement line. The effect of higher subcooling temperature in agreement with previous studies results in which higher cooling rate and more drastic temperature drop. The aim of this study is to make a better understanding of the multiple water impinging jets quenching technique in order to make further research in the area of enhancing the mechanical properties of steel by understanding effect of the quenching parameters and their characteristics in order to optimize the quenching technique for different applications.

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To achieve the established environmental goals, a significant transformation is requiredin the Swedish transport sector. This includes a shift away from fossil fuels and a greateremphasis on electrifying a larger portion of the vehicle fleet. The goal of this study is toevaluate the impact on the local distribution grid when integrating a high power chargeradjacent to a mobile battery storage system. In addition an investigation of the energyflows was conducted to assess the continuous operations of charger, battery and electricitygrid. The introduction of high power loads leads to higher power peaks in the system,which may affect the stability with respect to the voltages, currents and harmonics in thegrid. This thesis was conducted in collaboration with Gävle Energi AB, which is a local energycompany that is active in the area around Gävle. In total two models were created inorder to simulate both the energy flows and grid stability. The first model was conductedin MATLAB and used to evaluate the energy flows for the scenarios of low and high load.The second model was conducted in OpenDSS to evaluate the grid stability for a total of6 scenarios. The scenarios are as follows: the initial electricity grid, the grid with a highpower charger integrated and the grid with both a high power charger and a solar parkintegrated, for both low and high load cases. The results of the study showed that high power loads affected the local electricity gridmost during low load since it entailed high load peaks during that period. The effect ofintegrating a high power charger in a grid with radial grid topology is that the voltageis reduced and harmonics increased in loads connected to the same node. The effect ofintegrating a solar park instead increases the voltage and reduces the harmonics in loadsconnected to the same node. The energy flow evaluation showed that the battery hadthe potential to be continuously used for both the low and high load cases. However,during low load the battery had the potential to provide frequency regulating services tomaximize the income.

High Voltage Direct Current (HVDC) bushings are insulated devices designed to facilitate the safe passage of electric current across an earthed barrier. Understanding air conductivity is of utmost importance in the design of HVDC components, which is determined by ion density and ion mobility. Previous research has indicated a correlation between air conductivity, air humidity and phenomena on HVDC surfaces. This thesis aims to investigate and elucidate how adsorbed water may contribute to air conductivity. To accomplish this objective, an experimental study is conducted employing ellipsometry to measure the water layer thickness as a function of relative humidity and applied voltage. The results exhibit a thickness consistent with prior studies in the absence of applied voltage, but reveal an altered thickness when voltage is applied. While definitive conclusions cannot be drawn from this thesis alone, the findings provide some support for the hypothesis from earlier research, suggesting the involvement of surface phenomena in air conductivity. The experimental procedure presented in this thesis can be further expanded and refined to gain a more comprehensive understanding of the surface reactions at play. This could further develop the understanding of the factors influencing air conductivity in HVDC systems and contribute to the advancement of design methodologies in this field.

China is the largest energy consumer worldwide, with a fast-growing rate. But the energy and environmental problems brought by its unbalanced energy structure and low energy efficiency restrict the sustainable development of China. The Distributed Energy System (DES) is one of the internationally recognized solutions to the problems. To enhance the implementation of the DES under China’s scenario, the thesis develops computational models for the Combined Cooling, Heat, and Power (CCHP) and Separated Cooling, Heat, and Power (SCHP) systems for a Micro Energy Grid in northeast China using MATLAB. The objective is to minimize the overall expenditure, energy use, and carbon emission equivalents. The results show that the CCHP system reduces 18.62% of the overall expenditure and 35.02% of the carbon emission equivalents than the SCHP system. The CCHP system has a promising prospect in China with better Greenhouse Gas emissions reduction and economic performance. / Kina är världens största energikonsument, med en snabb tillväxttakt. Men de energi- och miljöproblem som orsakas av den obalanserade energistrukturen och den låga energieffektiviteten begränsar Kinas hållbara utveckling. Distribuerade energisystem (DES) är en av de internationellt erkända lösningarna på dessa problem. För att förbättra implementeringen av DES enligt Kinas scenario utvecklar avhandlingen beräkningsmodeller för kombinerad kylning, värme och kraft (CCHP) och separerad kylning, värme och kraft (SCHP) för ett mikroenerginät i nordöstra Kina med hjälp av MATLAB. Målet är att minimera de totala kostnaderna, energianvändningen och koldioxidutsläppen. Resultaten visar att CCHP-systemet minskar de totala utgifterna med 18,62 % och koldioxidutsläppen med 35,02 % jämfört med SCHP-systemet. CCHP-systemet har lovande utsikter i Kina med bättre minskning av växthusgasutsläpp och ekonomisk prestanda.

In this study, 16 wind power Environmental Impact Assessments (EIA) from Brandenburg, Germany have been reviewed, looking especially at how well they address impacts on bats, as they might be the species most affected by wind turbines. On an annual basis, about    240 000 - 300 000 bats are estimated to die because of wind power impacts. Specifically, wind power in forests is considered to be very harmful to bats. Nonetheless, wind power in forests is becoming more popular because of the required rapid expansion of renewable energies in Germany. The review was conducted using a specialized method for evaluating the quality of Environmental Statements designed by Lee and Colley (1991) in the 1990s. The method uses a letter grading system and is based on different criteria that focus on having a comprehensive review of all important parts of the EIA. The results showed that the EIAs were just satisfactory in addressing bat impacts, this is largely matching with results of previous studies on EIAs and bats. Although EIAs scored very differently in all evaluated categories, there were clear trends of rather good grades within the categories that aimed at assessing bat activity and worse grades in the categories that were concerned with the actual measures taken to avoid the impacts on bats. The report especially suggests that wind power planners pay especially more attention to implementing higher cut-in wind speeds and conduct a 2-year post-construction mortality survey. This could also help to further the understanding of wind turbine impacts on bats. Lastly, can be said that based on the applied method, most EIAs conducted for wind farms in Brandenburg generally address potential impacts on bats adequately, but there is also a lot of room for improvement.

A significant proportion of construction and demolition (C&D) waste is encompassed within the broader category of global waste. The handling of C&D waste is subject to the influence of a tripartite of environmental, social, and economic factors. An extensive comprehension of C&D waste management can be attained by examining the construction industry, waste management, transportation, and non-governmental organisations (NGOs). The escalating aggregate demand and landfill practices significantly threaten developing nations' natural resources, despite the national government's regulatory measures. The present study employed a qualitative research approach and a multi-level perspective (MLP) framework to investigate the various actors, factors, and levels that impact the management of C&D waste. The present analysis relates independently to investigating lock-in determinants, encompassing exogenous and endogenous pressures and socio-technical transitions. Bengaluru's management of C&D waste encompasses a diverse array of stakeholders, including real estate organizations, urban development agencies, construction firms, both formal and informal markets, a solitary C&D processing plant situated at the periphery of the city, unapproved landfills located in abandoned stone quarries, local transportation providers, governance bodies, and low-carbon building methodologies. Furthermore, it is imperative to note that there exist significant deficiencies in the execution of C&D waste management by established protocols, as well as their enforcement. This is compounded by an acute shortage of facilities for the collection and disposal of such waste, insufficient vehicular resources at the disposal of the Bruhat Bengaluru Mahanagara Palike (BBMP), limited participation from stakeholders, negative attitudes towards the effective use of recycled materials and the repurposing of building components, a lack of incentivisation and punitive measures, inadequate awareness among proprietors and constructors of private edifices, and the indiscriminate dumping of C&D waste, which has led to the obstruction of commuting and communal well being. The effects of landfills on wildlife, such as avian migration and urban inundation, have prompted a transition towards more ecologically sound management of C&D waste in Bengaluru. Formulating sustainable strategies for managing C&D waste in Bengaluru is encouraged to incorporate socio-economic and environmental factors, business models, and governmental cooperation. The importance of sharing information, the power of nudging people to alter their habits, and the value of considering new approaches to building are also highlighted.

The growing global demand for clean energy is critical, and wind power plays a crucial role in addressing this need. The increasing demand is driving advancements in the field of offshore wind power and one promising innovation is the counter-rotating vertical axis turbines (CRVT), specifically designed for floating wind power installations. The aim of this project was to develop a dynamic simulation and 3D visualization of a floating wind turbine using CRVT technology. In this project, simplified force models were created with the aim to incorporate more complex models from experts in wind and water dynamics in the future. The simplified force calculations included gravity, buoyancy, the Morison equation, as well as forces from a simple mooring and a generator. The implemented aerodynamic forces were obtained from a complex model developed by an expert in aerodynamics. The simulation was conducted in Matlab, utilizing first-principal physics for dynamics calculations. All the measurements used to compute the geometry of the wind turbine were imported from a CSV file. Finally, the RK4 method was employed to compute the steps, and a Maya model was created for the visualization of the wind turbine. In conclusion, the simulation successfully enabled the wind turbine's motion in all six degrees of freedom and provided a visual representation of the results. However, significant approximations were made, and additional validation is necessary to ensure the accuracy of the simulation.

As energy prices increase and the effect of global warming hits the world harder, the need of reducing our energy use, and by that decreasing our environmental footprint increases. According to the International Energy Agency the energy consumption hit a new record in 2019 with 419 EJ, corresponding to 36,6 Gt of carbon dioxide emissions. The building sector accounts for 40 % of the total energy consumption. According to the International Energy Agency, energy optimizing is the main key in the transit towards a more sustainable world and energy audits, or energy mapping, is in many cases the first step towards energy optimization. Sustainable Intelligence is a company working for long term, sustainable solutions for properties all over Sweden as well as Norway, Finland, Poland, and Latvia. Property automation is the main competence of the company. Another large sector at the company is the energy sector, where energy audits, energy declarations and energy consultations are made. This report aims to analyze the energy audit process of Sustainable Intelligence and hopefully find solutions to make their work more efficient. The study includes a case study where the energy audit process of Sustainable Intelligence was implemented and analyzed. The study showed that the current method used by SI has a good structure but that there is a room for improvements.