Solar energy and regional coordination as a feasible alternative to large hydropower in Southeast Asia

Kais Siala,Stefano Galelli,Thanh Duc Dang,Afm Kamal Chowdhury

doi:10.1038/s41467-021-24437-6

Abstract

Strategic dam planning and the deployment of decentralized renewable technologies are two elements of the same problem, yet normally addressed in isolation. Here, we show that an integrated view of the power system capacity expansion problem could have transformative effects for Southeast Asia’s hydropower plans. We demonstrate that Thailand, Laos, and Cambodia have tangible opportunities for meeting projected electricity demand and CO2 emission targets with less hydropower than currently planned—options range from halting the construction of all dams in the Lower Mekong to building 82% of the planned ones. The key enabling strategies for these options to succeed are solar PV and regional coordination, expressed in the form of centralized planning and cross-border power trading. The alternative expansion plans would slightly increase the cumulative costs (up to 2.4%), but substantially limit the fragmentation of additional river reaches, thereby offering more sustainable pathways for the Mekong’s ecosystems and riparian people.

Highlights

Strategic dam planning and the deployment of decentralized renewable technologies are two elements of the same problem, yet normally addressed in isolation
By running our framework over the period 2016–2037, we show that the regional electricity demand and CO2 emission targets can be met by constructing only 82% of the planned dams in Thailand, Laos, and Cambodia
We perform a power system optimization of the Lower Mekong region that takes into account the existing power infrastructure, the projected costs of technologies, as well as future electricity demand and emissions reduction targets

Summary

Introduction

Strategic dam planning and the deployment of decentralized renewable technologies are two elements of the same problem, yet normally addressed in isolation. We demonstrate that Thailand, Laos, and Cambodia have tangible opportunities for meeting projected electricity demand and CO2 emission targets with less hydropower than currently planned—options range from halting the construction of all dams in the Lower Mekong to building 82% of the planned ones. There might be multiple alternatives to this plan: the availability of regional grid interconnections[13,14] and renewable energy sources, solar photovoltaic (PV)[15], suggests that dam development may be partially offset by deploying renewable technologies in low-cost and well-accessible areas[16]. A complementary strategy is the design of more sustainable dam portfolios[17] Whether any of these alternatives is technically feasible and economically reasonable for it to succeed remains an open question

Methods

Results

Conclusion