AbstractThe United Nation’s 7th Sustainable Development Goal (SDG7) is to ensure access to affordable, reliable, sustainable and modern energy for all. A key challenge in achieving SDG7 is providing access to the estimated 0.9 billion people living in rural areas without access to electricity. In Nepal, factors including political unrest, challenging geography, and a weak economy, have limited electricity access. However, micro-hydropower has been used to provide electricity in rural areas. The technology is mostly manufactured locally, with the Nepali government supporting communities with a subsidy that funds approximately 50% of the total project cost. Manufacturing companies fulfil the roles of designer, manufacturer, and installer with the local community providing labour during the construction phase. The combination of locally manufactured equipment that is subsequently owned and operated by the community provides a unique range of challenges. This thesis explores the opportunity to improve the reliability of the technology and the operational sustainability of projects. To do so, a new design methodology is proposed that allows an existing technology, the Turgo turbine, to be adapted for local manufacture and use in Nepal.
The proposed design methodology, known as ‘Design for Localisation’, frames the direction of the thesis. Firstly, an understanding of the local context is developed. A field-based methodology is developed and used at 24 micro-hydropower plants to consider factors affecting their operational sustainability. Findings from the site study are combined with a detailed evaluation of the project process, using available literature and interviews with stakeholders, resulting in an improved understanding of how strengths and weaknesses in the operational sustainability of plants develop.
Secondly, design solutions for local manufacture are developed. A survey of manufacturing companies is used to identify the local availability of materials and processes. These findings indicate determine the method for manufacture of the turbine blade. Subsequently, computational fluid dynamics is used to optimise the performance of the runner, increasing efficiency from 69.0 to 82.5%. In collaboration with a local manufacturing company, a locally appropriate design is developed and manufactured. CAD, the internet, and additive manufacturing are used to transfer and physically replicate the digital design as a mould for casting.
Thirdly, local testing and monitoring is used to evaluate the design. A hydrodynamic testing rig is developed at Kathmandu University. The locally manufactured Turgo turbine runner and an imported off-the-shelf Turgo turbine runner are tested under the same conditions, and the results compared. A site-based installation is used to understand the performance of the runner once integrated with ancillary sub-systems, and in environmental conditions.
Finally, the efficacy of the Design for Localisation process and its further application is considered. A scaling method, allowing the Turgo turbine design to be adapted for any site with appropriate geography, is presented. An open-source approach is proposed to improve the availability of the design, enable subsequent improvement and further local adaptation to other contexts.
|Date of Award
|23 Mar 2021
|Sam Williamson (Supervisor) & Julian D Booker (Supervisor)