Workshop A3: Nexus approaches in Land-Water-Energy Interactions
Chaired by Holger Hoff
Presenting speakers :
This study assesses the differential contributions of the large (LHP) and small (SHP) scale hydropower development to regional water and energy security in the largest Spanish transboundary basin (the Duero basin), as well as the related cumulative environmental impacts. The results suggest that large hydropower has higher contributions and plays a critical role to ensuring regional water and energy security, with better performance in 10 of the 12 indicators assessed. Currently SHP generates higher cumulative impacts per unit of power generated in the basin for the four impact categories considered, mainly due to the massive number of existing plants. In absolute terms, LHP shows higher values for impact indicators on Disturbance of the river regime and Habitat loss, whereas SHP shows higher impacts on Connectivity and Disturbance of ecosystems. Based on observations from the analysis, the authors consider that LHP has great potential to lead Spain towards a low carbon, low water footprint and import independent energy system if the possibilities that enhanced hydraulic pumping systems coupled to intermittent renewables offer are envisioned and exploited. They also estimate that there might be great potential for optimization of the hydropower system by tapping all the possible services provided by existing reservoirs, some of which are single purpose, and concentrating hydropower production around existing infrastructure with potential for energy production (existing reservoirs or irrigation or distribution canals). This would enable reduced impacts compared to an extended development of small individual projects that require their own diversion device. Besides, the appropriateness of using the installed capacity as the standard for setting the difference between LHP and SHP is discussed. It is believed to fail in setting up two homogeneous categories of technological alternatives with significant similarities and inter-differences in terms of environmental and sustainability performance, thus providing poor elements of judgement to inform decision making on future energy technology roadmaps.
Finally, an emerging lesson from the Duero and Spanish experience that could be scalable and transferable to water planning in other basins is the importance of prioritizing the premise of the maximum value with minimum intervention. Tapping and maintaining all the potential services provided by certain infrastructures like dams can prevent from the need of additional developments, thus reducing the cumulative impacts and maximizing the economic and sustainability value of the projects.
Solar energy is considered as a viable renewable energy resource with a significant potential to change the energy balances of the MENA countries by relieving the dependency on non-renewable fossil fuels. When used for in desalination processes, solar energy also offers possibilities for improved water and food security, since the desalinated water can be used to meet the increasing water demands in the domestic, industrial and agricultural sectors. Solar-based desalination systems are particularly attractive for the MENA region, given the high levels of solar radiation as well as the relatively law operation and maintenance costs.
As with other technological innovations, the introduction of the solar energy for desalination into the existing governance systems brings about the need for institutional and social changes. Countries in the MENA region share a common natural and climatic context in terms of the scarcity of freshwater resources, the abundance of solar radiation, and the forecasted adverse effects of climate change. However, these countries differ when it comes to their approaches for realizing the necessary institutional and social changes towards the adoption of solar-based desalination. Currently, many countries in the region use fossil fuels for seawater desalination, whereas recent investments have been made to diversify the energy mixes towards increasing the share of renewable energy resources, including the use of solar energy.
Against this backdrop, the use of solar energy for water desalination is socially and politically relevant for improving the water, energy and food securities in the MENA region. However, the understanding regarding the governance implications of solar-based desalination on water-energy-food nexus is limited. The proposed paper aims to improve this understanding through providing a comparative review of the MENA countries. Particular attention will be paid to identifying the key political, institutional and social factors that influence the diffusion of solar-based desalination in the MENA region. The implications of these factors will be analysed for the water, energy and food securities of MENA countries, and the resulting advancements and/or impediments for the water-energy-food nexus are compared.
In this work, we analyse the complex interconnections between conflicting water uses in the Omo River Basin. Following the Participatory and Integrated Planning (PIP) procedure (Castelletti and Soncini-Sessa 2006), we frame the water resource management problem at the basin level by simulating the effects of the operation of the Gibe cascade scheme (Gibe I, II, and III dams in place) on the water-energy-food nexus. In particular, we take into account the following water-related interests: hydropower production from the Gibe hydropower dams, the commercial irrigation (the Kuraz sugar plantation), the environment in the Lower Omo Valley, and the recession agriculture which is the livelihood for the indigenous population. We model the system by using the fully distributed and physically explicit hydrological model TOPKAPI-ETH. This model accounts for the main physical hydrological process and includes the description of the reservoirs and hydropower plants by means of simple operating rules. We simulate the runoff according to different scenarios of energy production targets and commercial crop schemes. We assess the effects of the scenarios on the water-related interests by computing quantitative indicators expressing the different water uses’ interests. The assessment contributes in understanding the conflicts between current water management practices and the potential trade-offs associated to different management strategies. Results show that the most crucial conflicts take place between commercial agriculture and environment, and between hydropower and recession agriculture. The environment and the recession agriculture indicators are very sensitive to the alteration of the natural flow pattern consequent to the hydropower dams operation. The presence of commercial irrigation contributes to worsen the impacts.
In order to attain the national development goals it therefore appears that there is a need for integrated quantitative assessments of future development trajectories for the country, accounting both for cross sector inter-linkages and competing demand for resources. These findings jointly call for informed cross-sector strategic planning and cross-sector linkages. At the moment, there is a window of opportunity in this regard in Zambia since several of the current policies are under revision.
Target audience: We invite interested participants from all disciplines and at all career stages specially early stage PhD student and postdocs.
Date and time: Jun 15th, 13:30 – 15:15
Location: ZUK, Osnabrück, Room 1
- Holger Hoff