The total energy demand in the transport sector represented 48.80% of the total consumption in Ecuador throughout 2016, where 89.87% corresponded to the road transport sector. Therefore, it is crucial to analyze the future behavior of this sector and assess the economic and environmental measures towards sustainable development. Consequently, this study analyzed: (1) the total energy demand for each vehicle class and fuel type; (2) the GHG (greenhouse gas) emissions and air pollutants NO_x and PM₁₀; and (3) the cost attributed to the fuel demand, between 2016 and 2035. For this, four alternative demand scenarios were designed: BAU: Business As Usual; EOM: Energy Optimization and Mitigation; AF: Alternative Fuels; and SM: Sustainable Mobility using Long-range Energy Alternatives Planning system. After analysis, the EOM, AF, and SM scenarios have advantages relative to BAU, where SM particularly stands out. The results show that SM compared to BAU, contributes with a 12.14% (141,226 kBOE) decrease of the total energy demand, and the economic savings for this fuel demand is of 14.22% (26,720 MUSD). Moreover, global NO_x and PM₁₀ emissions decreased by 14.91% and 13.78%, respectively. Additionally, accumulated GHG emissions decreased by 13.49% due to the improvement of the fuel quality for the vehicles that mainly consume liquefied petroleum gas, natural gas, and electricity.

Currently, hydropower is the principal renewable energy source; however, climate change is increasing the frequency of extreme events, such as floods, droughts, erosion, and sedimentation of rivers, which produce uncertainty with regard to hydroelectric generation. Thus, this study aimed to analyze the climate change projections for the hydropower systems of Ecuador based on data from 14 projects studying scenarios according to the Shared Socioeconomic Pathways from the Intergovernmental Panel on Climate Change. The study examined the period from 2010 to 2020 with historical data, determined the tendency, defined a database year, and then projected the scenarios to 2050. The quantitative methodology used time-series statistics for Ecuador’s hydropower inflow to calculate the deviation over recent years and develop a model to simulate future power generation. The results showed that hydropower in Ecuador is expected to decrease considerably through to 2050 due to meteorological changes. In this calculation of the Shared Socioeconomic Pathways, the selected scenarios showed a reduction in SSP5 of 11.5%, SP2 of 16.2%, and SSP4 of 18.2% through to 2050, indicating that the opportunities for hydroelectric production in the face of climate change are variable, but the challenges are broad. In Ecuador, the projections of reductions in hydropower generation represent a sensitive issue, especially knowing that, in 2020, 87% of the energy grid in the country depended on hydroelectric production.

Ecuador is a small Andean country located in the western hemisphere of South America. The country has 361.747hm3 annual superficial water resources; As a result, Ecuador, in the last fifteen years (2005 to 2020), has been rapidly developing hydropower projects to triple the production in this renewable source. There were eight new hydroelectric plants constructed in Ecuador among 2007 and 2015 invested close to USD 6 billion the projects. Increased the energy response with renewables; for example, in 1985, the country produced 4 TWh, in 2005-registered 7 TWh, and to 2020, 24 TWh. According to the Electricity Corporation of Ecuador in 2020 reported that generated around 80% of all electricity through hydropower; thus, the article aims to critically analyze the development of hydropower in Ecuador in recent years and establish general energy projections to 2030 to expand the fields of knowledge and perspectives. The paper methodology is quantitative, according to scientific editorial sources, articles, investigative documents, and collects data from government agencies that regulate energy development in Ecuador. It is conclusive between a projection’s calculation, Ecuador will need for the year 2030 around 43 TWh, 47 TWh, or 52 TWh to supply the energy grid, according to the scenarios proposed (low, medium, high). Although hydropower will be essential to contribute to this requirement, the country has a barrier because hydropower is very sensitive to external factors of diverse nature, generating an uncertainly future directly associated with climatic effects.

The present review shows a perspective of hydropower development, a renewable source that has a global installed capacity of 1308 GW with 9000 stations around the world. The document showed the advantages and the impacts around the different author’s perspectives. The review method consisted of defining a criterial find of articles, thesis and scientific material to consolidate the knowledge and give a viewpoint of this renewable source. The results show extensible affectations from hydropower expansion and this renewable energy source that requires analysis and study to delineate development sustainable with multidisciplinary areas of reflection. Moreover, the investigated results worldwide show that hydropower is not a pollution source; however, it has environmental impacts, social and cultural; such facilities may affect land, homes, and natural habitats. It concludes that the development of hydroelectric projects brings benefits but entails unavoidable impacts; therefore, it recommends that these affections must evaluate with detailed studies based on sustainability criteria.

Nowadays, hydropower is the principal renewable; however, climate change increases extreme events such as floods, droughts, erosion, and sedimentation of rivers that produce uncertainty in hydroelectric generation. Thus, this document aims to analyze the climate change projections in the hydropower systems of Ecuador based on data from 14 projects studying the scenarios ac-cording to the Shared Socioeconomic Pathways from the Intergovernmental Panel on Climate Change. The study period starts from 2010 to 2020 with historical data, collects the tendency, defines a database year, and then projects the scenarios to 2050. The quantitative methodology uses a statistic on Ecuador's hydropower obtained inflow time series to calculate the deviation over the last years and develop a model to simulate future generation. The results show that the hydropower in Ecuador is expected to decrease considerably through 2050 due to meteorological changes. In this calculation of the Shared Socioeconomic Pathways, the selected scenarios show a reduction in SSP5 of 11.5%, SP2 of 16.2%, and SSP4 of 18.2% to 2050, concluding that the oppor-tunities for hydroelectric production facing climate change are variable, but the challenges are broad. In Ecuador, the projections of hydropower plants represent a sensitive issue of their re-ductions, especially knowing that the country had an energy grid in 2020 that depended on 87% of hydroelectric production.

INTRODUCTION: Hydropower is an extensively used renewable source; in 2016, 159 countries reported benefiting; currently, there are around 9,000 projects in operation due to the competitive cost of generating a similar cost such as thermal energy such as coal, oil, or gas in the range of USD 4 - 5 cents US dollars per kilowatt-hour. OBJECTIVE: Investigate the results of hydroelectric development in the face of the changing climate and the generated impacts, making hydropower a subsector of special attention to discussing the global projection. METHOD: Bibliographic review to reflect on the global context of hydroelectricity based on scientific studies. RESULTS: Hydropower projects a 6% decrease for Europe by 2070, from 20% to 50% throughout the Mediterranean, and a reduction in usable capacity in most hydroelectric plants between 61% for the 2040 scenario– 2069 globally. DISCUSSION AND CONCLUSIONS: Globally, hydropower presents a broad vision of the advantages, and little said about the disadvantages and problems, and only there are specific studies that shown various project studied in a general way. It is shown that hydroelectric production has several implications in the face of the changing climate and impacts generated in ecosystems by the deployment of large infrastructures.