This report details the development of a Flood Early Warning System (FEWS) for the Tana Basin in Kenya, executed by a multidisciplinary team from the Delft University of Technology. Recognizing the Tana Basin’s vulnerability to flood risks, exacerbated by climatic variability, limited funds, and limited available data, the project proposes a model that combines computationally efficient hydrological and hydrodynamic modelling with robust stakeholder collaboration. The study area comprises the entire Tana Basin, with a specific focus on the flood-prone area near Garissa used for validation. The FEWS developed incorporates local and scientifi-cally derived knowledge to forecast floods, aiming to aid the transition from a technologically intermediate to a technologically advanced FEWS. Through an iterative process of model selection, validation, and stakeholder feedback, the system attempts to integrate the GR4J hydrological model in SuperflexPy and combines this with the Super Fast INundation of CoastS (SFINCS) model. Data sources include global remote sensing datasets like FABDEM & CHIRPS. Furthermore, it uses the water level gauge data provided by the Water Resource Authority of Kenya, as well as TAHMO weather station data.

The report concludes by reflecting on the modelling techniques for both the hydrological and hydrodynamic models and provides recommendations for the further development of a FEWS in the Tana Basin in Kenya. The implementation of the hydrological model was not able to propagate external flows through the network, making it poorly suited for use in the Tana Basin. The hydrodynamic model works decently well in flood conditions but overpredicts flooding during regular flow conditions. Recommendations on stakeholder engagements and data-sharing practices to foster a resilient flood management system in the Tana Basin include more comprehensive Memoranda of Understanding (MoU) and stricter adherence to the Disaster Risk Management Framework of the United Nations.

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River discharge is traditionally required with a lot of measurements and data. However there are areas where discharge data is not available. In this research a tool is developed based on hydraulic geometry relations to estimate the discharge of a river in bank full state near Narok, Kenya. With the help of the Global Navigation Satellite System (GNSS) coordinates are converted in to cross-sections of the river in a bank full state. Discharges are assumed and verified through the hydraulic geometry relations of the cross-sections. These discharges are simulated in Super-Fast INundation of CoastS (SFINCS) to simulate the flash floods of Narok and an accurate estimate of the river discharge in a bank full state was obtained. ... Read more

Ethiopia’s energy demand is expected to increase sevenfold in the coming 30 years, resulting in increased variable renewable electricity (VRE) production by solar PV and wind. Energy storage acts as a buffer that mitigates the effects of over- or under-capacity in production by VRE. With 97% of global bulk energy storage, pumped hydro storage is the most widely used and mature energy storage method. With its long operational life, high round-trip efficiency (80%) and stable cost trajectory, it is a beneficial option for many energy systems. However, drawbacks of pumped storage include heavy technical, site-specific restrictions, long construction times and high initial capital investment requirements.

This study investigates if Ethiopia’s energy pathways benefit from adding pumped storage, where to build it, and if storage increases system resilience. The long-term energy planning tool OSeMOSYS is used, which allows for detailed investigation into system dynamics whilst parallelly minimising costs. OSeMOSYS enables the investigation into Ethiopia by looking at an extensive host of techno-economic
specifications and supply and demand dynamics from the electrification of transport and integration of variable renewables to residential cooking demands.

This report discusses thirteen scenarios which are separated into three main categories: Base Case (3), Emission Penalty (EMI) (6) and Varying Wind Capacity and Seasonality (WND) (6). The base case introduces pumped storage to the energy pathways. The EMI scenario characterises three pathways for carbon pricing. In the WND scenario, wind power’s capacity factor and seasonality are altered to
investigate the potential effects of using more accurate local data or prioritising some supply zones on the energy system configuration. Additionally, the most favourable locations for solar PV and wind are combined with potential PHS locations to find optimal sites for storage construction.

The results of the research show that pumped hydro storage is adopted into the energy system in all scenarios, following both a diurnal and seasonal (dis)charge pattern. Variable renewable integration increases by an average of 10% from the addition of storage (78 GWh). The emission penalty increases the electrification of residential cooking demand and boosts VRE penetration but does not integrate
storage integration further than the base case due to reaching the upper limit of the storage capacity set in the planning experiments. Lastly, the changes in capacity factor and seasonality have a marginal effect on the energy pathways.

Pumped hydro storage increases the energy system’s resilience to climate-driven seasonal uncertainties and prices due to fossil fuel and carbon price uncertainties by making it less dependent on fossil fuels, decreasing vulnerability for potential emission penalties and seasonal capacity fluctuations. The introduction of PHS does not increase overall system costs, making it a prime candidate for large-scale energy storage in Ethiopia, combined with the stable levelised cost of storage and high maturity ... Read more