Residential building sector accounts for significant share of primary energy demand in Sweden. Worldwide, generation from photovoltaic (PV) distributed energy resources is increasing, yet their potential in Sweden has been underdeveloped, in particular due to high system costs. Recent drop in module prices could however trigger more interest in such systems. In this thesis, the financial performance of residential PV plant utilizing the most recent data is carried out. The specific aim is to determine whether private investment into a PV system can be cost-effective. In the analysis, a grid-connected PV microgenerator with nominal power of 5.5 kWp, 34 m2 of arrays and 6 kW inverter is assessed. Expected lifetime of the system is 25 years, where 80% of the electricity output is self-consumed and 20% fed back to the main grid. Discount and escalation rates are utilized to calculate simple payback period, net present value, benefit-cost ratio, cost of conserved energy and internal rate of return (IRR) of the investment. Further, a scenario analysis is worked out to determine the change in the microgenerator’s performance outside of baseline set of parameters. The results are presented both under the default market conditions and with the inclusion of government support mechanisms. The PV plant did not financially perform well under the default conditions. State rebates and tax credit significantly enhanced the results and contributed to the cost-effectiveness of the investment. In the baseline scenario with government support, significant positive results in all the metrics used in the financial appraisal were yielded. The IRR also indicated that loans at various interest rates could be obtained to finance the PV system. The study emphasized the necessity of government support if a faster uptake of distributed PV systems is desired in Sweden. The results of this thesis can be utilized by potential investors (consumers) in their decision-making process, especially when they face an opportunity cost of investment. / COMPLEX - Knowledge Based Climate Mitigation Systems for a Low Carbon Economy, a EU FP7 project (2012-2016)

We all take for granted that if we press the switch, the lights turn on; that to charge our phone we just need to plug-in the charger and that food is always safely stored in our fridge. but what would happen in the event of a blackout? are we really conscious of how much we rely on electricity? could we survive without it, even for a few days?The current electricity network is strongly centralised, with electricity generated in large power plants and distributed through transmission networks to the final consumers. With increasing energy demand and renewable energies entering the scene, centralised systems have proven to be very stiff: lacking the flexibility to adapt to sudden demand fluctuations and being unable to deal with strong peaks, with the consequent risk of blackouts.Small, decentralised energy systems can be placed closed to the consumers, avoiding distribution losses and adding flexibility to the network. In particular, small cogeneration units can simultaneously generate heat and electricity; thus, also fulfilling our heating requirements and increasing energy efficiency. However, when there is no or little heat demand (e.g. during the summer), the heat produced by the cogeneration engines cannot be utilised and they need to be shut down. This is the reason why small-scale cogeneration cycles are rarely seen and have not been widely adopted yet.This PhD focuses on the injection of water in a specific small-scale cogeneration technology, the micro gas turbine (mGT) cycle. Thanks to water injection, the production of heat and electricity is decoupled; therefore, the operation of the units is not anymore dependant on the heating demand and they can be used any time during the year. The objective of this thesis is to analyse the numerical, experimental and economic aspects of the so-known micro Humid Air Turbine cycle. The aim is to bring mGTs closer to the market so as to contribute to a more secure, future energy network, where blackouts are avoided at all times. / Doctorat en Sciences de l'ingénieur et technologie / info:eu-repo/semantics/nonPublished

Orientador: Ennio Peres da Silva / Dissertação (mestrado) - Universidade Estadual de Campinas, Faculdade de Engenharia Mecânica / Made available in DSpace on 2018-08-27T02:08:03Z (GMT). No. of bitstreams: 1 Castro_RodolfoDamasiode_M.pdf: 3152478 bytes, checksum: a4e0e80e4ac1f8804a7b3aa8589139b4 (MD5) Previous issue date: 2015 / Resumo: A busca por meios de geração de energia para atender às necessidades humanas com menores impactos sociais e ambientais é constante. A geração de energia elétrica por meio de fontes renováveis na forma distribuída, ou não centralizada, é um meio ou método de minimizar tais impactos. O objetivo da pesquisa foi analisar a viabilidade econômica, frente a tarifa de energia elétrica das concessionárias locais, da utilização de sistemas de geração solar em residências brasileiras situadas nas capitais dos estados, na capital federal, Brasília e na cidade de Campinas (SP). Diferentes situações de dimensionamento foram utilizadas para dois tipos de sistemas: um sistema fotovoltaico puro, para atender toda a necessidade energética da residência, incluindo o chuveiro elétrico, e um sistema solar híbrido, composto por aquecimento solar para atender a demanda por água quente no banho em conjunto com geração fotovoltaica para atender as necessidades em equipamentos elétricos. As situações de dimensionamento utilizadas foram três, onde em cada uma o sistema fotovoltaico foi projetado para uma determinada produção de energia. Os sistemas fotovoltaico e de aquecimento solar foram dimensionados com o auxílio dos softwares PVSyst e Dimensol, respectivamente. O custo total dos sistemas foi estimado a partir de pesquisa em lojas com endereço eletrônico na rede de computadores e de orçamentos fornecidos por empresas do ramo. Determinou-se o preço final da energia elétrica convencional para todas as cidades a partir da tarifa definida pela ANEEL, do valor médio do PIS efetivo cobrado pelas concessionárias e da alíquota de ICMS que os governos estaduais recolhem. Após realizados os cálculos, chegou-se ao resultado de que somente nas cidades de Macapá (AP) e Boa Vista (RR), devido principalmente ao baixo custo das tarifas de energia elétrica, o usuário não economizaria com a instalação dos sistemas. Porém, em cidades de elevada tarifa, como Belém (PA) e Belo Horizonte (MG), o usuário pagaria cerca de R$ 0,30 por quilowatt hora consumido a menos / Abstract: The search for power generation means to meet human needs with lower social and environmental impacts is constant. The distributed generation of electricity by renewable energies is a method to minimize those impacts. The research aimed to analyze the economic viability against local electricity tariff of the use of solar power generation systems in Brazilian households located in the capitals of the states, in the federal capital, Brasilia, and in the city of Campinas (SP) Different sizing situations were used for two types of systems: a pure PV system to meet all the energy needs of the residence, including electric shower, and a hybrid solar system, consisting of solar heating to meet the demand for hot water in the bath together with photovoltaic generation to meet the needs in electrical equipment. Sizing situations used were three, where in each one the PV system is designed for a certain production of energy. The photovoltaic systems and solar heating were sized with the help of the softwares PVSyst and Dimensol, respectively. The total cost of the systems was estimated by a research in webstores and budgets provided by companies in the field. Was determined the final price of conventional electricity to all cities from the tariff set by ANEEL, the average value of the effective PIS charged by concessionaires and ICMS aliquot that state governments collect. After performing the calculations, came to the result that only the cities of Macapa (AP) and Boa Vista (RR), mainly due to the low cost of electricity tariffs, the user does not save due to the installation of the systems. However, in cities of high tariff, as Belém (PA) and Belo Horizonte (MG), the user would save about R$ 0.30 per quilowatt-hour / Mestrado / Planejamento de Sistemas Energeticos / Mestre em Planejamento de Sistemas Energéticos