Long Term Sustainability of Standalone PV Systems for Community Services: Case Studies from Rwanda
Independent thesis Advanced level (degree of Master (Two Years)), 20 credits / 30 HE creditsStudent thesis
This thesis was developed with a twofold aim in mind. In first place, to study some of the components that are required to achieve long term sustainability of standalone PV systems for community services. This means, to put in place the necessary ingredients to ensure that standalone PV systems that power schools, health centers or administration offices, among other public institutions, are able to last for their typical life time (20-25 years).
In particular, the focus of this theoretical part of the thesis is mainly set on both the technical and socio-technical dimensions of long term sustainability. As part of the first one, the study delves into aspects related to PV system design and quality in installations, sustainable system use and operation, as well as maintenance theory. As part of the socio-technical dimension, research in the literature has been done mainly about those social concepts related to the community surrounding a PV system, aspects related to system operation from a user’s perspective, as well as maintenance seen from a socio-technical point of view. Complementarily to the previous two, other dimensions such as the financial, governmental, environmental and related to project management are also introduced.
The second part of this thesis is based on work done during a one month trip to Rwanda. During this time three main case studies were developed around two schools and one health center, in order to assess the degree of fulfilment of the different dimensions of long-term sustainability in these sites, setting most of the efforts on both the technical and the socio-technical dimensions. Additionally, three complementary (and shorter) visits to two administration offices and an additional school also took place. These visits plus some interviews to several Rwandan companies completed the picture of long-term sustainability of standalone PV systems in the Rwandan context.
Although the components and the installation of standalone PV systems in recent national Rwandan programs were of high quality, there was generally a lack of adequate direct and indirect lightning protections, in spite of the fact that Rwanda is one of the places with highest keraunic levels in the world. In some cases, previous systems had poor designs, used low quality wiring or installed low quality batteries, not in compliance with international standards. In terms of maintenance and component replacements, these elements were almost never taken into account as part of any original project plan, including financial and human resources. However, although maintenance structures only started to be defined in national programs after system installation, they all lacked the actors and instruments to properly trace quality in maintenance.
In socio-technical terms, efforts to engage or transfer system operation and energy efficiency knowledge, in the form of trainings for end-users, did not seem to be sufficient. Therefore, some sites experimented a notable load increase or a load shift. In most situations, energy consumption could be optimized, either by using energy efficient appliances (e.g. namely thin clients, energy efficient fridges) or by optimizing the frequency and total time of their use (i.e. autoclaves in health centers). Simple but yet effective operation strategies could also be easily adopted in order to adequate energy use to energy generation, as per the examples included in this thesis. Last but not least, remote monitoring solutions should be considered in the future as means to improve operation and maintenance, especially in wide national projects.
Place, publisher, year, edition, pages
Standalone, PV system, Off-grid, Long-term sustainability, Maintenance, Rwanda, Socio-technical dimension, Community services, Rural electrification, Photovoltaics, Solar energy, State of charge, Preventive maintenance, Quality in maintenance, Lead-acid battery, Lightning protection, Remote monitoring, Community awareness, Ownership, Load management, Maintenance structure, School, Health center, Administration office, Nyamirama, Bungwe, Janja St. Jêrome.
IdentifiersURN: urn:nbn:se:du-23094OAI: oai:DiVA.org:du-23094DiVA: diva2:970782