The development of high capacity factor solar power plants is an interesting topic, especially when considering the climate and economic conditions of a location such as the Chilean Atacama Desert. The hybridisation of solar photovoltaic (PV) and concentrating solar power (CSP) technologies for such an application is a promising collaboration. The low cost of PV and dispatchability of CSP, integrated with thermal energy storage (TES), has the promise of delivering baseload electricity at a lower cost than what could be achieved with CSP alone. Therefore, the objective of this work was to evaluate whether or not a hybrid PV-CSP plant is more economically viable, than CSP alone or hybrid PV-diesel, for baseload generation. To analyse this hypothesis, a techno-economic optimisation study of a PV-CSP hybrid plant with battery storage and fossil fuel backup was performed. In doing so, a methodology for the identification of optimum solar hybrid plant configurations, given current technology and costs, to best satisfy specific location weather and economic conditions was developed. Building on existing models, for the PV and CSP components, and developing models for further hybridisation, a complete PV-CSP model was created that could satisfy a baseload demand. Multi-objective optimisations were performed to identify optimal trade-offs between conflicting technical, economic and environmental performance indicators. For the given economic and technical assumptions, CSP hybridised with fossil fuel backup was shown to provide electricity at the lowest cost and have the lowest project capital expenditure. This configuration showed a 42% and 52% reduction in the levelised cost of electricity in comparison to CSP alone and hybrid PV-diesel, respectively. It also provides a 45% reduction in CAPEX in comparison to CSP alone. PV-CSP integration increases capital costs and the cost of electricity, but reduced the use of fossil fuel backup and thereby reduced emissions, when compared to CSP with fossil fuel backup. However PV-CSP showed a 97% reduction in CO2 emissions when compared to hybrid PV-diesel. Furthermore, it showed a 35% and 46% reduction in LCOE in comparison to CSP alone and hybrid PV-diesel.

Access to clean and affordable energy is a prerequisite for human development. In order to achieve access to sustainable energy for all innovation in rural electrification is needed. Decentralized renewable energy technologies in form of Solar Home Systems and Mini-grids possess the potential of electrifying a large number of rural households which cannot be connected to the national grid with local available energy sources. However, the deployment of Mini-grids is facing barriers such as a lack of private investments. By building on already existing SHSs swarm grids can enable households to trade electricity and use their excess electricity to supply additional loads. Swarm grids as an evolutionary bottom-up approach to electrification can overcome some of the obstacles regular Mini-grids face and play a vital role in improving electricity access. As part of this thesis a model has been developed which allows for simulating the electricity flow including line losses in swarm grids of any size on an hourly basis. The model facilitates the gaining of a better understanding for the impact global parameters (e.g. distance between households) have on the feasibility of swarm grids. A field trip to Bangladesh has been undertaken in order to obtain input data for simulating different cases in the model created. The simulations performed indicate that in a swarm grid the generated excess energy of SHSs which so far is wasted can supply the demand of households without SHS as well as commercial loads such as irrigation pumps. Overall the results point towards swarm grids being an innovation with the potential of improving rural electricity access by building on existing infrastructure.

Renewable energies are fluctuating and the bigger its share on the Swedish energy market, the more fluctuating are the prices. Therefore, CHP plant operators as VEAB in Växjö, are more and more struggling to be competitive. There is, hence, a need of alternative options for the use of produced electricity, rather than being dependent on such a volatile and unclear market. Hydrogen production through water electrolysis could therefore be an alternative to be decoupled from the electricity business and instead being part of a promising, future hydrogen economy. Since state-of-the-art electrolysers have efficiencies between 51% and 75%, it was assessed that some of the efficiency losses could be recuperated by implementing the excess heat in an existing District heating (DH) grid. Calculations of the base scenario electrolyser with a power input of 870 kW showed, that an increase of the overall temperatures of the returning mass flow of the DH grid from 0,05°C to 0,23°C should be achievable. The economic analysis showed, that for this size of hydrogen production unit, the minimum hydrogen selling price (MHSP) would be 6,64 €/kg, which is not competitive on today’s market. However, the sensitivity analysis showed, that by a decreased investment cost, lower electricity prices and especially by scaling up the base scenario, the MHSP could be lowered significantly. Assuming a reduction of investment costs of 20% and scaling up the electrolyser by 1000% to 8700 kW, the MHSP resulted in 1,9 €/kg, a competitive price on the market. This study revealed that hydrogen production could be part of the future business model of CHP plant operators and provides a guideline on the feasibility of such a project.

With the increase in the world energy demand and environmental incentives, renewable energy sources (RES) need to determine their place as some of the primary power sources in future power systems. However, due to uncertain energy production, renewable energy sources cause unbalance in the power system due to the unsynchronized supply and electricity demand. The intermittent power production causes undesired power fluctuation, affecting the power quality and reliability of the power source. Energy storage is one solution that is debated to increase the reliability of renewable energy production. This thesis aims to model and simulate hybrid energy storage system (HESS), constructed of hydrogen and ultracapacitor energy storage, to investigate different operation strategies for everyday use and crises. The two different energy storage technologies complement each other, where hydrogen fuel cells can produce power for long periods of time while the ultracapacitor can quickly maintain the balance of production and consumption of electricity for a short instance. The HESS showed promising results for emergency power supply and supported service operation strategies. In case of a power shortage, the HESS could cover for the disconnected production. The ultracapacitor proved to be a suitable component due to its ability to support the shortcomings of a hydrogen energy storage system. Moreover, the HESS could meet the requirements to deliver support services. However, further studies have to be done to investigate how the HESS can deliver multiple support services to increase profit and help maintain the power system's balance and security.

This thesis studied a new method for continuous calculation of boiler efficiency at Säbyverket:s boiler 11, 12 and 13 located in Jakobsberg, Sweden. Säbyverket three boilers are supplying peak power to Stockholms “Nordvästra nät” with district heat during lack of power in the district heating grid. The plant was originally designed to run on oil, but new regulations and environmental knowledge caused E.on who own the plant to convert boiler 12 to a multifuel boiler burning wood powder mainly and bio-oil secondary.  Boiler 11 and 13 changed to be operated with bio-oil. Recent data on the boiler efficiency after the conversion showed boiler efficiencies not in line with the expected efficiency. Therefore, a study was conducted to forward a different method of calculating boiler efficiency at Säbyverket. The requirement of the new method was that it should be calculated in a way that avoided existing uncertainties.  Today’s method was based on the direct method for calculating boiler efficiency for boiler 11 and 13. Due to difficulties in calculating mass flow for solid-state fuel, boiler 12 had a method based partly on the indirect method, and partly based on the direct method. A new method for the three boilers based on the indirect method was produced. Comparing results showed that the current method for boiler 11 resulted in a way to low calculated boiler efficiency compared to the new indirect method. While boiler 12 method was confirmed giving the same results with the two methods. Boiler 13 had a double-calculated density when calculating the delivered power from the oil fuel. This caused a calculated boiler efficiency over 100 %. When compensating for this factor the two different methods gave the same mean result. However, the new method based on the indirect method was significantly more stable when calculating boiler efficiency with a sampling time with mean-minute values. Results from the calculations show that the method for calculating boiler efficiency for boiler 11 and 13 should be changed to the new method described in the report. However, no improvements could be achieved by changing the method for boiler 12. Therefore, it is recommended to keep the existing method for calculating boiler efficiency for boiler 12. / Säbyverket tre pannor byggdes mellan 1977 - 1982 och bestod ursprungligen av tre stycken fossiloljeeldade fartygspannor om 47 MW var. På grund av hårdare miljökrav samt ett hårdare miljöarbete av E.on, konverterades panna 11 och 13 till bioolja 2006 respektive 2016. Panna 12 konverterades till en tvåbränsleeldad panna med träpulver som primärbränsle och bioolja som sekundärbränsle år 2003. Beräkningen av pannverknignsgrad var efter konvertering opålitlig framförallt för panna 11 och 13, den beräknade pannverknigsraden visade på pannverknignsgrader som inte var överensstämde med det förväntade resultatet. På grund av osäkerheten som fanns i beräkningarna ämnade examensarbetet att reda ut om en alternativ metod för beräkning av pannverknignsgrad skulle ge en pålitligare beräkning av pannverkningsdgraden. En ny metod togs därför fram för beräkning av pannverknigsrad baserat på den indirekta metoden. Metoden beräknar pannverkningsgraden genom förluster, istället för kvoten mellan levererad och tillförd effekt vilket dagens metod baseras på. En stor fördel med den indirekta metoden är att den kan beräknas relativt. Detta betyder således att tillförd bränslemängd inte behöver vara känd indata vid beräkning. Eftersom fastbränsleflöden är svåra att mäta är detta en fördel för framförallt panna 12. Eftersom panna 12 eldar två bränslen itererades respektive massandel bränsle fram för beräkning av pannverkningsgraden. Den nya metoden beräknar följande förlustfaktorer: Rökgasförluster, oförbränt i fast rest (askförluster), oförbränt i gasfas och strålning och ledningsförlsuter.  Resultatet från de två olika metoderna visade att nuvarande metod för panna 11 beräknade en för låg pannverkningsgrad i jämförelse med den nya metoden. Panna 12 visade samma resultat vid beräknad pannverkningsgrad med de två olika metoderna. Dagens metod för Panna 13 dubbelräknade densiteten vid beräkning av massbränsleflödet, detta resulterade i en beräknad pannverkningsgrad över 100 % då den tillförda effekten minskade med en faktor om 0,9. Vid kompensering av den dubbelräknade densiteten var den beräknade medelverkningsgraden samma för de två metoderna. Den nya metoden resulterade dock i ett stabilare resultat vid beräkning av pannverkningsgrad med mindre svängningar i jämförelse med dagens metod.  E.on rekommenderas att byta metod för beräkning av pannverkningsgrad för panna 11 och 13. Den nya framtagna metoden resulterar i en förbättrad och stabilare beräkning av pannverkningsgraden jämfört med dagens metod. Panna 12:s metod bedöms vara lika nogrann som den nya metoden, således rekommenderas det att behålla dagens metod för panna 12. En korrigering i beräkningssystemet för beräkning av massbränsleflödet från huvudoljeledningen bör göras för panna 13. Detta genom att ta bort termen Olja.dens vid beräkning av P13_Molja för korrekt mätning. Detta bör göras även om ny metod appliceras. Metoden ska även vara applicerbar på andra av E.on:s anläggningar. Kravet är att bränslet ska vara homogent och den mätutrustning som är beskriven i rapporten ska vara installerad i anläggningen.

Berners är en stor aktör inom försäljning och service av bilar och transportfordon i Jämtland och Västernorrland. På sina anläggningar i Sundsvall och Östersund tillhandahåller Berners bland annat biltvättar och rekond och dessa verksamheter ger upphov till stora utsläpp av vatten och kemikalier. För att minska utsläppen har Berners installerat indunstarrening, som är en reningsteknik som bygger på att smutsigt tvättvatten förångas och farliga partiklar faller ur. Med den här tekniken elimineras nästan alla kemikalieutsläpp och ungefär 90 procent av tvättvattnet återanvänds. Indunstarrening kräver mycket energi i form av el som i dagsläget köps in. Reningstekniken ger även upphov till spillvärme i både luft och vatten som i dagsläget inte utnyttjas. Syftet med arbetet är att undersöka potentiella förbättringsåtgärder för Berners biltvättar, för att göra de befintliga och eventuella framtida anläggningar bättre. Detta genom att undersöka möjligheterna av att utnyttja spillvärme och minska behovet av köpt el, genom egenproduktion av el med solceller. Målet är att genom detta ta fram underlag för Berners när de ska besluta om eventuella förändringar av de befintliga tvättarna samt vid byggnation av nya anläggningar. Underlaget ska bestå av resultat för minskade energibehov, minskade utsläpp, minskade behov av köpt el och livstidsbesparingar för förbättringsåtgärderna. I arbetet undersöktes tre olika förbättringsåtgärder. Installation av FTX-ventilation för att värma ingående luft till en angränsande lokal med utgående luft från det rum där indunstaren är placerad, installation av en plattvärmeväxlare för att värma vätskan i en radiatorkrets med utgående destillat från indunstaren samt installation av solceller för att minska behovet av köpt el till indunstaren. Monokristallina-, polykristallina- och tunnfilmssolceller samt olika storlekar av installerad area undersöktes. Minskade energibehov beräknades för FTX och VVX, minskade behov av köpt el beräknades för solceller och minskade utsläpp av koldioxidekvivalenter samt livstidsbesparingar beräknades för alla tre förbättringsåtgärderna. Resultaten visar på att en kombination av att installera FTX, VVX och polykristallina solceller genererar de största livstidsbesparingarna och de största utsläppsminskningarna. Installation av en plattvärmeväxlare för att ta vara på spillvärme i destillat är den enskilt bästa åtgärden för att minska energibehovet. Berners kan vid installation av en eller flera av de olika förbättringsåtgärderna minska energibehoven och utsläppen från biltvättarna, minska behovet av köpt el samtidigt som de kan spara pengar. / Berners is a major player in the sale and service of cars and transport vehicles in Jämtland and Västernorrland. At its facilities in Sundsvall and Östersund, Berners provides, among other things, car washes and auto reconditioning and these operations give rise to large discharges of water and chemicals. To reduce emissions, Berners has installed evaporator treatment, which is a treatment technique based on the evaporation of dirty washing water and the fallout of dangerous particles. With this technology, almost all chemical emissions are eliminated and approximately 90 percent of the washing water is reused. Evaporator cleaning requires a lot of energy in the form of electricity that is currently purchased. The treatment technology also gives rise to waste heat in both air and water, which is currently not used. The purpose of the work is to investigate potential improvement measures for Berner's car washes, to make the existing and possible future facilities better. This is done by investigating the possibilities of utilizing waste heat and reducing the need for purchased electricity, through own production of electricity with solar cells. The goal is to thereby produce a basis for Berners when they are to decide on any changes to the existing washes and when building new facilities. The basis shall consist of results for reduced energy needs, reduced emissions, reduced need for purchased electricity and lifetime savings for the improvement measures. The work examined three different improvement measures. Installation of FTX- ventilation to heat the incoming air to an adjacent room with outgoing air from the room where the evaporator is located, installation of a plate heat exchanger to heat the liquid in a radiator circuit with outgoing distillate from the evaporator and installation of solar cells to reduce the need for bought electricity for the evaporator. Monocrystalline, polycrystalline and thin film solar cells as well as different sizes of installed area were investigated. Reduced energy needs were calculated for FTX and VVX, reduced needs for purchased electricity were calculated for solar cells and reduced emissions of carbon dioxide equivalents as well as lifetime savings were calculated for all three improvement measures. The results show that a combination of installing FTX, VVX and polycrystalline solar cells generates the largest lifetime savings, as well as the largest emission reductions. Installing a plate heat exchanger to take advantage of waste heat in distillates is the single best measure to reduce energy needs. When installing one or more of the various improvement measures, Berners can reduce the energy needs and emissions from the car washes and reduce the need for purchased electricity, while at the same time saving money.

The heat demand in Sweden has stagnated and district heating companies must take action to sustain in the market. Based on this background this study combines a PEST and SWOT analysis to produce a basis to suggest general strategies suitable for district heating companies in southern Sweden. The analysis found that both investments into activities outside of the heating market, as well as further development of current systems, are viable options. Increasing the awareness and knowledge about district heating companies was also identified as a factor that could entail several benefits.

This degree project aims to investigate whether it is possible to establish photovoltaic (PV) systems inexisting Swedish wind farms from a production and permit perspective. The degree project examinesthe conditions for the establishment of PV systems in three wind farms owned by Eolus Vind AB. The results show the importance of investigating the prerequisites of the location to find the rightproject site for PV power plants. In addition, the results show that Swedish laws do not oppose PVpower plants being built in wind farms. The production calculations also show that a more evenelectricity power production is achieved when PV systems are installed on open areas in the windfarms, but that the proportion of installed power will be limited by the connection points within eachwind farm. The conclusion is that wind farms are suitable with a combination of solar and wind power, but theconnection point will be a major factor in the amount of installed solar power that can be added to theproject areas.

This study has explored the potential for lowering the subscripted power of 25 MW for one of the connection points between the local power grid and its overhead power grid for a local grid owner. The potential for doing so through hard, direct load control of electrical domestic heating and domestic water heating for detached houses with a fuse size of 16-25 A is evaluated for 12 different scenarios. The scenarios are found by combining a customer participation of 25, 50, 75 and 100 percent with a maximum allowed duration for load control of two, three and four hours respectively. A function describing the need for electrical power for domestic heating as dependent of the outdoor temperature is developed and combined with a model that is used for simulating hot water usage and a model that describes the power demand of a domestic water heater. Furthermore, a control function is incorporated to ensure that households are not subjected to load control for a longer period than allowed and that all households bear the same burden in this respect.  The results show that a power of 1,0-4,1 MWh/h can be redistributed, but that the potential is heavily limited by the returning load that occurs. Due to the long duration of the critical peaks that are being redistributed, up to 5-10 hours, returning load occurs even though load control has not yet been finalized. The returning load leads to a bigger amount of power having to be redistributed and therefore limits the potential for the new subscripted power that can be achieved. Furthermore, the maximum aggregated power for the investigated year amounts to 25,9 MW. Still, a new subscripted power of 21,8–24,9 MW is theoretically deemed to be achievable. The most likely outcome however is thought to be a lowering of the subscripted power to at least 23,4–24,4 MW, having taken the composition of type of heating systems as well as the most likely customer participation into account.

About 12% of the greenhouse gas emissions and 40% of the total energy use in the EU derive from the buildings. User behavior, construction, and HVAC systems has a significant impact on a building’s energy use. If a building is to be energy-efficient it is important to understand how all these parameters are connected. This study is motivated by the need to decrease the energy use in buildings to reach the goals of energy use and greenhouse gas emissions.  In this thesis, measurements of indoor climate and electricity use, together with time diaries was used to create input data for an energy simulation model of a retirement home. A parametric study was conducted to simulate how energy demand was affected by changes in five different parameters in an office building. Also, two different energy-efficiency indicators were used to see how indicators can affect the perceived energy-efficiency of buildings. High amount of airing and low electricity use had the most impact on the heating demand in the retirement home, and electricity use had the highest impact on the total energy demand in the office building. The model of the retirement home using data gathered on-site had 24% higher energy use than the model using standard user input data. In the office building, total energy demand for heating and cooling could be lowered with 12-31% by lowering the electricity use with 30% compared to standard user input data. For office buildings the most important thing to lower total energy demand seems to be lowering the electricity use. Using today’s standard user input data does not correspond well to using on-site gathered data in a retirement home and it is therefore important to develop the standard user input data further. The indicator kWh/m2, seems to promote buildings with low occupancy. This could lead to buildings being utilized in an in-efficient way. The indicator kWh/m2 should either be replaced or combined with an indicator that takes occupancy into consideration. / Runt 12% av utsläppen av växthusgaser och 40% av den totala energianvändningen i EU kommer från byggnader. Brukarbeteende, konstruktion och HVAC-system har signifikant påverkan på en byggnads energianvändning. Om en byggnad ska bli så energieffektiv som möjligt är det viktigt att förstå hur dessa parametrar hör ihop. Denna studie motiveras av behovet att minska energianvändning i byggnader för att nå målen för energianvändning och utsläpp av växthusgaser.  I denna avhandling användes mätningar av inomhusklimat och elanvändning, tillsammans med tidsdagböcker, för att skapa indata till en energisimuleringsmodell av ett ålderdomshem. En parameterstudie genomfördes för att simulera hur energibehovet påverkades av ändringar i fem olika parametrar i en kontorsbyggnad. Två olika indikatorer för energieffektivitet användes också, för att se hur olika indikatorer påverkar hur en byggnads energieffektivitet uppfattas. Hög grad av vädring och låg elanvändning hade störst påverkan av energibehovet i ålderdomshemmet, och i kontorsbyggnaden påverkades det totala energibehovet mest av elanvändningen. Modellen av ålderdomshemmet där data insamlad på plats användes hade 24% högre värmebehov än modellen som använde standardiserade brukarindata. Det totala energibehovet för värme och kyla i kontorsbyggnaden kunde sänkas med 12-31% genom att sänka elanvändningen med 30% jämfört med standardiserad brukarindata. Det viktigaste för att få ner det totala energibehovet i kontorsbyggnader verkar vara att sänka elanvändningen. Att använda dagens standardvärden för brukarindata överensstämmer inte väl med att använda data insamlad på plats för ett ålderdomshem. Det är därför viktigt att vidareutveckla standardiserad brukarindata. Indikatorn kWh/m2 verkar främja byggnader med låg beläggning. Detta skulle kunna leda till att byggnader utnyttjas på ett ineffektivt sätt. Indikatorn kWh/m2 skulle därför behöva ersättas eller kombineras med en indikator som även tar byggnadens beläggning i beaktande.