The Greater Mekong's Climate‐Water‐Energy Nexus: How ENSO‐Triggered Regional Droughts Affect Power Supply and CO₂ Emissions

Abstract

The Greater Mekong Subregion is a transnational area bound together by the Mekong River basin and its immense hydropower resources, historically seen as the backbone of regional economic development. The basin is now punctuated by several dams, successful in attracting both international investors and fierce criticisms for their environmental and societal impacts. Surprisingly, no attention has been paid so far to the actual performance of these infrastructures: is hydropower supply robust with respect to the hydroclimatic variability characterizing Southeast Asia? When water availability is altered, what are the implications for power production costs and CO2 emissions? To answer these questions, we focus on the Laotian–Thai grid—the first international power‐trade infrastructure developed in the region—and use a power system model driven by a spatially distributed hydrological‐water management model. Simulation results over a 30‐year period show that production costs and carbon footprint are significantly affected by droughts, which reduce hydropower availability and increase reliance on thermoelectric resources. Regional droughts across the Mekong basin are of particular concern, as they reduce the export of cheap hydropower from Laos to Thailand. To put the analysis into a broader climate‐water‐energy context, we show that the El Niño Southern Oscillation modulates not only the summer monsoon, but also the power system behavior, shaping the relationship between hydroclimatological conditions, power production costs, and CO2 emissions. Overall, our results and models provide a knowledge basis for informing robust management strategies at the water‐energy scale and designing more sustainable power plans in the Greater Mekong Subregion.

Solar energy and regional coordination as a feasible alternative to the 'Battery of Asia' plan

“…This is necessary to ensure that the capacity expansion model is informed with correct hydropower profiles. A detailed description of calibration and validation exercises is reported in 22,23 .…”

“…However, some dam portfolios may be technically or economically unfeasible, because the frameworks with which they are designed do not represent the role played by dams within power systems. For example, concentrating dams within a few sub-basins may provide an opportunity to balance installed capacity with ecosystem services, but such a plan may be impaired by the cost of developing an adequate transmission infrastructure 22 , or if the intermittent production of hydropower dams cannot be absorbed by the existing thermoelectric facilities 23 . These are the fundamental mechanisms captured by the tools used to study the integration of renewable technologies within existing grids, which combine long-term capacity expansion and detailed power system operations [24][25][26] .…”

Opportunities for Robustness of Water Footprints in Electricity Generation

“…Water resources are consumed in the cooling of thermoelectric power plants and in the production of hydroelectric power. Chowdhury et al (2021) investigate this nexus of resources and determine how energy production variability is explained by ENSO climate patterns within the Mekong River basin in Southeast Asia. Greenhouse gas emissions and costs of operating the electricity grid respond to ENSO-driven fluctuations in water availability.…”

“…Greenhouse gas emissions and costs of operating the electricity grid respond to ENSO-driven fluctuations in water availability. In drought years, operational costs and resultant greenhouse gas emissions rise due to the reduced availability of hydroelectric power generation capacity (Chowdhury et al, 2021). The authors, in their analysis, place dams and thermoelectric power plants in a broader context, focusing on understanding the variable hydrologic patterns of the region, and how they drive temporal water availability.The work by Chowdhury et al (2021) facilitates an interesting discussion on the role of water resources management in electricity production and subsequent greenhouse gas emissions under hydrologic uncertainty.…”

“…In drought years, operational costs and resultant greenhouse gas emissions rise due to the reduced availability of hydroelectric power generation capacity (Chowdhury et al, 2021). The authors, in their analysis, place dams and thermoelectric power plants in a broader context, focusing on understanding the variable hydrologic patterns of the region, and how they drive temporal water availability.The work by Chowdhury et al (2021) facilitates an interesting discussion on the role of water resources management in electricity production and subsequent greenhouse gas emissions under hydrologic uncertainty. Chowdhury et al ( 2021) compliment work regarding the electricity sector in California, which showed the 2012-2016 drought in California caused an estimated increase of carbon emissions by 10%-33% compared to predrought conditions (Gleick, 2015;Hardin et al, 2017;Kern et al, 2020).…”