Kenya is a country with high energy poverty rates while millions of people, especially in the rural areas, rely on kerosene lamps as a source of lighting. The usage of kerosene is linked with the degradation of different social and economic aspects and parameters, such as health, education, income etc. At the same time, grid extension and connection to that require a very high capital. In other words, the state’s limited financial resources do not allow the sustainable development of rural electrification while rural families cannot afford the installation and consumption costs of electricity in the areas where the national grid has reached. The latest years, alternative solutions to grid connection such as solar lamps, larger solar kits and microgrids have made their appearance in Kenya and they offer the opportunity to people to turn into cleaner and healthier sources of lighting and electricity. This MSc thesis has two goals. The first one is to measure and quantify various differences on socio-economic parameters between kerosene lamps and solar lantern users. The second one is to identify, design and compare alternative solutions to grid extension for rural electrification. Therefore, this work is separated in two parts. The first part is a socio-economic impact study, conducted in Kenya between May and July 2014 as an interview survey. The second part is a techno-economic comparative study between the different alternatives for rural electrification that exist nowadays in Kenya, which has as a base the designing and sizing of renewable energy microgrids for five remote communities in the country. The results of the socio-economic study showed that the source of lighting has a great impact on people’s quality of life, aspects of development and escape from poverty. Families that use solar lanterns recorded better education, health and income levels while the kerosene lamp usage seem to have great connection to drudgery, high expenditures, bad school grades and degraded living conditions. As far as the techno-economic comparative study is concerned, it has been shown that both solar lanterns and microgrids have a significantly lower cost in comparison to the respective expenditures of rural families in Kenya for kerosene lamps and fuel. As a result these technologies are able to cover the gab that is left by the low or zero rates of grid extension in remote areas and they can be an affordable, healthier and more sustainable solution for those rural households that rely on kerosene as a source of lighting and lack at the same time access to essential services such as phone charging, radios and other appliances.

The study carried out in this master thesis is part of a larger project led by Energynautics GmbH focusing on renewable energy development in the Caribbean. One of the Caribbean states, consisting of multiple islands, has set a target of 30 % of renewable energy in the power sector by 2030. The first objective of the thesis is to develop optimal generation capacity expansion plans for two different islands of this country, utilizing solar PV generation, which is the only available renewable energy resource. To achieve this objective, three main tasks are identified. The first is the development of an optimal generation capacity expansion plan for the next three years using the optimization tool HOMER Energy. At the beginning only diesel generation is present on the islands. For each study case year, the installed capacity of PV and BESS is optimized and enabling technologies such as curtailment (controllability of PV) and grid-forming inverters are deployed. The second task focuses on the development of a new dispatch strategy, improving on the black box dispatch algorithms built into HOMER. The dispatch strategy minimises the cost of electricity generation and is based on a rolling 48 hours forecasts of the load and PV. It is implemented in MATLAB and linked to HOMER via the built-in MATLAB interface. As HOMER is focused on generation expansion and dispatch and inherently neglects the grid, a grid study is required to assess the stability of the network. This study is the last task of the thesis and is limited to determined steady-state voltage and the asset loading on one of the studied islands through load flow simulations in DIgSILENT PowerFactory. It is shown that there are no major issues even at high PV shares, however, grid performance can be improved if the PV unit is equipped with reactive power capability to control the voltage. A study on the impact of the Q(U)- control and the PQ-capability of the PV and BESS inverters is performed. / Studien som genomförts i detta examensarbete är en del av ett större projekt vilket leds av Energynautics GmbH med fokus på utveckling av förnybar energi i Karibien. En av de Karibiska staterna, bestående av flera öar, har ett mål på 30 % förnybar energi i elkraftssektorn innan 2030. Första syftet med examensarbetet är att utveckla optimala utbyggnadsplaner för produktionskapaciteten för två olika öar i detta land, med användning av solcellsproduktion, vilket är den enda tillgängliga förnybara energikällan. Den första uppgiften är utvecklingen av en optimal utbyggnadsplan för produktionskapaciteten för de kommande tre åren med optimeringsverktyget HOMER Energy. Från början fanns det bara dieselgeneratorer på öarna. För varje studerat år optimeras den installerade kapaciteten av PV och BESS samt aktivering av möjliggörande teknologier som begränsning av PV-produktion och grid-forming växelriktare. Den andra uppgiften fokuserar på utvecklingen av en ny driftsstrategi, förbättring av den basala driftsalgoritm som är inbyggd i HOMER. Driftsstrategin minimerar kostnaden av elproduktionen och är baserad på en 48 timmars prognos av laster och PV. Den är implementerad i MATLAB och kopplad till HOMER via det inbyggda MATLABgränssnittet. Eftersom HOMER fokuserar på produktionsutbyggnad och drift och i praktiken försummar elnätet, krävs en studie av elnätet för att utvärdera stabiliteten av elnätet. Studien av denna sista uppgift i examensarbetet är begränsad till att bestämma spänningen vid jämnviktsläge och den utvärderade lasten på en av de studerade öarna genom belastningsfördelningsberäkning i DIgSILENT PowerFactory. Det visade sig att det inte fanns några stora problem även med stora andelar PV, men elnätets prestanda kan förbättras om PV-omriktarna är utrustade med reaktiv effektstyrning som kontrollerar spänningen. En studie avinverkan från Q(U)-styrning och PQ-kapacitet av PV- och BESS-växelriktare har utförts.