Design of a Sustainable Energy System for an Eco-Village: A Case Study of Bulindo Village

Aims: To plan and design Bulindo eco village to accommodate 10,000 residents with the main emphasis on the sustainable energy system that meets the energy demand under available constraints i.e. maximum annual capacity shortage, allowable emissions, operating reserve and the minimum renewable energy fraction
Study Design: The planning and design was accomplished by ascertaining the current state of Bulindo village as well as determining the energy requirements of this village and the available resource potential in the area. Using the above data as input to computer simulation model using HOMER software an energy system configuration that meets the energy demand for this village was obtained.
Place and Duration of Study: The study was done in the School of Engineering under the College of Engineering, Design, Art and Technology of Makerere University, Kampala-Uganda from January 2013 to May 2013.
Methodology: After gathering the relevant information for the study i.e. energy demand of the village using a field survey and the primary energy resource potential at Bulindo got from a climate file for Wakiso district provided by Meteonorm software, HOMER was used to model, simulate and optimize the energy system that meets the energy requirements of the village under available constraints. HOMER also assisted in determining both the technical and economic feasibility of the designed system.
Results: From computer modeling and simulation, it was found that Bulindo has an overall electrical energy demand of 49 MWh/day. The demand is maximum from 18:00-22:00hrs with a peak of 4.6 MW. The fresh water supply system for the village which was modeled as a deferrable load had an energy demand of 680 kWh/day. The demand is highest during the dry season i.e. from January to March and from June to September with a peak demand of 170 kW. The designed energy system consisted of a PV array, a wind generator, the grid, battery bank, a converter and a biomass generator which acts as backup. This system can meet up to 95% of the annual energy demand while the remaining 5% will be supplied by the national grid. The unit cost of the electricity is $0.028 and the project life is 50 years.
Conclusion: The sustainable energy system for Bulindo eco village to be moved in by 2025 has been designed. The designed system is believed to offer a better performance due to its sustainability as well as its ability to meet all the energy requirements of the village i.e. both energy and fresh water demand. Simulation results demonstrate that using green energy sources such as solar PV and wind generators will reduce the operating costs, greenhouse gas emissions and particulate matter. In addition, the system also supplies fresh water for residential, commercial and industrial usage. The amount of energy produced by the system is 63,658,616 kWh/year at a unit cost of $0.028 /kWh. 76% of the generated energy is consumed by the system i.e. AC primary load and the deferrable load while the surplus (24%) is sold to the national grid which earns crucial revenue to the village for better management of the system hence guaranteeing sustainability. However, the challenge will be getting the human resource to maintain and manage this system.