The high share of impermeable surfaces in cities modifies the terrain characteristics that facilitate natural water flow and balance. The street network, an impervious surface on its own, is also the impetus for developing other impervious surfaces by facilitating access. The purpose of this work is to assess the interconnectedness between the underlying structural lines of the terrain and the street network for making informed decisions on locating green infrastructure to maintain water balance. For this purpose, the work measures the spatio-structural similarity between the co-located networks, assesses the variation of the measure with city size and relation to an indicator of water balance. Cross-sectional analysis is performed across a large sample of cities of varying sizes to extract generalized patterns of spatial structure and variations to size. The larger cities have low index values of spatio-structural similarity ranging between –0.2 and 0.2. The low index values for larger cities relate to the emergence of small-world properties in large street networks for functional efficiency and large street networks' web-like shape. Next, the paper identifies two zones based on the interconnectedness of the roads and the terrain. The spatial extent of a zone based on points where the arterial road intersects higher orders of drainage channels and ridgelines is associated with the number of above-normal wet conditions (SPEI ≥ 2.0) with the r-value of –0.30 at a p-value of 0.05. In summary, spatial statistics on spatial network data are helpful to extract trends inherent in the multi-layered network structure of cities to provide informed solutions. The policymakers and planners can use the spatial co-location patterns between street and terrain to make data-driven decisions to locate interventions for a nature-based resilient city.

Regional electricity interconnections are increasingly recognised as enablers of cost-effective power system expansion and deep decarbonisation in emerging economies. In East Africa, Kenya and neighbouring countries — Tanzania, Ethiopia, and Uganda — operate relatively low-carbon electricity systems; however, rapidly growing electricity de-mand and expanding thermal generation are placing upward pressure on grid emissions intensity, particularly in Kenya. This study examines whether planned cross-border in-terconnections can mitigate this trajectory using OSeMOSYS Global, an open-source least-cost capacity expansion model, comparing stand-alone national power systems against an interconnected regional grid over 2022–2050. Results show that interconnec-tion enables access to low-cost renewable electricity and facilitates surplus generation ex-ports, maintaining system-wide carbon intensity within climate-finance eligibility thresh-olds of 100 gCO2/kWh. Outcomes are heterogeneous: Ethiopia and Kenya incur cost in-creases (+USD 481 million and +USD 568 million respectively) attributable to transmis-sion capital expenditure, whereas Tanzania and Uganda achieve net cost savings (−USD 590 million and −USD 891 million) alongside substantial emissions intensity reductions of 141.9 and 280.5 gCO2/kWh respectively. Regional emissions equity is preserved, with modest intensity increases in Ethiopia and Kenya offset by large reductions elsewhere. These findings strengthen the case for climate-financed regional transmission as a scala-ble and equitable mitigation strategy in East Africa.

Regional electricity interconnections are increasingly recognised as enablers of cost-effective power system expansion, resilience and energy security in emerging economies. In East Africa, Kenya and neighbouring countries, namely Tanzania, Ethiopia, and Uganda, operate relatively low-carbon electricity systems; however, rapidly growing electricity demand and expanding thermal generation are placing upward pressure on grid emissions intensity. This study examines whether planned cross-border interconnections can mitigate this trajectory using OSeMOSYS Global v1.0.0, an open-source least-cost capacity expansion model, comparing stand-alone national power systems against an interconnected regional grid over 2022–2045. Results show that interconnection enables access to low-cost renewable electricity and facilitates surplus generation exports, maintaining system-wide carbon intensity within climate finance eligibility thresholds of 100 gCO₂/kWh. Outcomes are heterogeneous: Ethiopia and Kenya incur cost increases (+USD 481 million and +USD 568 million, respectively) attributable to transmission capital expenditure, whereas Tanzania and Uganda achieve net cost savings (−USD 590 million and −USD 891 million) alongside substantial emissions intensity reductions of 141.9 and 280.5 gCO₂/kWh, respectively. Regional emissions equity is preserved, with modest intensity increases in Ethiopia and Kenya offset by large reductions elsewhere. These findings strengthen the case for climate-financed regional transmission as a scalable and equitable mitigation strategy in East Africa.

This report examines the prospective role of nuclear and Small Modular Reactors (SMRs) within the complex energy transitions of Low and Middle-Income Countries (LMICs), offering a replicable energy planning framework and informing potential UK Government support. It underscores that while variable renewable energy (VRE) sources are foundational for decarbonisation, their high penetration can introduce significant system-level costs, often uncaptured by simplistic Levelised Cost of Electricity (LCOE) metrics, necessitating complementary firm, dispatchable capacity. Modelling indicates that SMRs could integrate meaningfully into fossil-fuel heavy systems (with limited hydro and geothermal as so-called “firm” renewable capacity) from approximately 2037–2045. This integration would be driven by carbon constraints and reliability needs, potentially contributing over 20% of generation by 2055. Conversely, in hydropower- dominated systems (that provide “firm” renewable capacity), SMRs are projected to play a more limited role, typically less than 2% of generation, as existing hydro and increasingly cost-effective battery storage largely meet demand. The viability of SMRs is contingent upon specific “triggers”, notably their capital costs falling below approximately $6,000–7,500 MUSD/GWe, alongside carbon prices exceeding $73–78 USD/ton, respectively. (At lower carbon prices, fossil-fuel alternatives provide the required “firm” capacity). Note that these numbers will change over time (as the energy system is dynamic) and will require updating annually. Construction delays significantly escalate total system costs, primarily by necessitating reliance on more expensive, often fossil-fuel-based, backup generation and incurring higher capital costs over time.