By Julien Harou, Mathaios Panteli, Jose Gonzalez Cabrera, Gloria Salmoral and Rose Sumner.
Traditionally planners considered the effects of water and energy systems on the other in simplified ways or not at all. This has often led to inefficient use of resources and a somewhat arbitrary allocation of benefits and costs across sectors and geographic regions. As explored in a recent Resilience Shift blog, the need to decarbonise energy systems is ‘introducing unprecedented interdependencies in multi-resource systems, and creating demand for integrated water-energy systems’.
A new study published by FutureDAMS researchers attempts to take on this challenge by demonstrating how water and energy systems can be planned to carefully and efficiently share benefits between stakeholders. The developed framework uses new methods of jointly designing river basins and energy systems, and demonstrates how portfolios of infrastructure investments and policy interventions can result in good outcomes under a range of plausible futures. The study shows the importance of coupling water and power system simulation when evaluating future system performance in complex and largely unpredictable circumstances, such as climate-driven high peak or highly fluctuating energy use events or droughts. A model-assisted multi-criteria design process is used to suggest synergistic combinations of infrastructure and policy interventions, such as irrigation canals, thermal and hydroelectric plants and multi-purpose reservoirs and their operating rules, to satisfy a range of objectives.
Figure 1: The water-energy network of the synthetic case study. How to identify fair and efficient ways to expand energy and water services in such a socio-economic engineered system?
This integrated system idea is illustrated with a simple synthetic case study (figure 1) where a network of water and energy components are linked through canals, rivers and transmission lines. Other physical infrastructures include reservoirs, power plants, or features of the system, such as agricultural zones, public water supply and energy demands. Both the water and energy sectors need to access to water in the Northern and Southern regions of the case study, while competition exists between irrigation, hydropower generation and public water supply. Future investments with infrastructure upgrades are studied over a 50-year time horizon to ensure that designs will be able to deal with multiple scenarios of water and energy demands and supply.
Figure 2: Different efficient combinations of infrastructure investments. New infrastructure is red, and sizes/widths of nodes/links are proportional to the scale of the proposed new asset. Overall these different future systems generate similar amounts of power and water supply, but which sectors benefit in what region is different in each panel. The paper shows how each of these plans corresponds to a different distribution of benefits between sectors and regions, each investment package coming with its own trade-offs.
In figure 2 we show 3 different optimised future water-energy systems that generate similar amounts of energy and water supply overall, but which sectors benefit and in what region is very different in each case. Being able to evaluate with stakeholders and decision makers the benefit distribution implications of different infrastructure investment bundles, such as those pictured above, will help planners better serve stakeholders and society more widely.
This study highlights the value of considering spatial relationships and interdependencies within joined up river basin – energy systems. It enables better synergistic design of complex resource systems with regional and sectoral trade-offs. The framework can assist planners in real resource systems where diverse stakeholder groups are mindful of receiving their fair share of development benefits. The FutureDAMS consortium is busy applying it with partners to FutureDAMS case-study countries.
For further details read the full paper ‘Spatial and sectoral benefit distribution in water-energy system design’.