Challenges for hydropower-based nationally determined contributions: a case study for Ecuador

Abstract

Hydropower is the dominant renewable energy source to date, providing over two-thirds of all renewable electricity globally. For countries with significant hydropower potential, the technology is expected to play a major role in the energy transition needed to meet nationally determined contributions (NDCs) for greenhouse gas (GHG) emission reductions as laid out in the Paris Agreement. For the Republic of Ecuador, large hydropower is currently considered as the main means for attaining energy security, reducing electricity prices and mitigating GHG emissions in the long-term. However, uncertainty around the impacts of climate change, investment cost overruns and restrictions to untapped resources may challenge the future deployment of hydropower and consequently impact decarbonisation efforts for Ecuador's power sector. To address these questions, a partial equilibrium energy system optimisation model for Ecuador (TIMES-EC) is used to simulate alternative electricity capacity expansion scenarios up to 2050. Results show that the share of total electricity supplied by hydropower in Ecuador might vary significantly between 53% to 81% by 2050. Restricting large hydropower due to social-environmental constraints can cause a fourfold increase in cumulative emissions compared to NDC implied levels, while a 25% reduction of hydropower availability due to climate change would cause cumulative emissions to double. In comparison, a more diversified power system (although more expensive) which limits the share of large hydropower and natural gas in favour of other renewables could achieve the expected NDC emission levels. These insights underscore the critical importance of undertaking detailed whole energy system analyses to assess the long-term challenges for hydropower deployment and the trade-offs among power system configuration, system costs and expected GHG emissions in hydropower-dependent countries, states and territories. Key policy insights • Ecuador's hydropower-based NDC is highly vulnerable to the occurrence of a dry climate scenario and restrictions to deployment of large hydropower in the Amazon region. • Given Ecuador's seasonal runoff pattern, fossil-fuel or renewable thermoelectric backup will always be required, whatever the amount of hydropower installed. • Ecuador's NDC target for the power sector is achievable without the deployment of large hydropower infrastructure, through a more diversified portfolio with non-hydro renewables.

Climate variability and change in Ecuador: dynamic downscaling of regional projections with RegCM4 and HadGEM2-ES for informed adaptation strategies

“…Moreover, climate-induced changes in agricultural practices are anticipated across tropical latitudes, spurred by rising temperatures and alterations in rainfall patterns. Particularly in the highlands of Ecuador, a projected decrease in precipitation could severely impact water resources, posing challenges to urban water supply and hydroelectric generation (Buytaert et al, 2009;Lawrence and Vandecar, 2015;Ovalle-Rivera et al, 2015;Carvajal and Li, 2019). Our study aligns with these observations, revealing significant vulnerabilities in specific ecosystems under the RCP 8.5 scenario.…”

Hydropower Production Benefits More From 1.5 °C than 2 °C Climate Scenario

“…This study only focuses on hydropower potential, while including the other renewable energy technologies (e.g., wind and solar) would not virtually affect the estimation of the hydropower capacity, as it does not compete for common resources and can be used for peak time hours (Anderson et al, 2006). It is indeed a more flexible and stable technology than other renewable energy technologies (Carvajal & Li, 2019). A consideration of the other technologies and renewable resource mix would benefit the whole energy system in the further work (Mesfun et al, 2017).…”

Hydropower Scenarios in the Face of Climate Change in Ecuador

“…Based on Carvajal's (2019) analysis of Ecuador's energy grid, it is clear that hydropower is affected by climate change and, thus, a partial equilibrium model is needed for the energy system. It was found that the proportion of Ecuador's total electricity produced by hydropower could vary significantly by 2050 (between 53% and 81%) and this could be attributed to a dry climate scenario, as well as social resistance that could limit the implementation of large-scale hydroelectric projects in the country [14].…”