This work evaluates the biogas production potential of the Ceibales landfill for feeding a power plant in the southern region of Ecuador. Biogas production is estimated through mathematical models that consider energy generation and technologies available to supply electricity plants. Characteristic landfill data are accounted for to analyze and develop these mathematical models. Once the generation capability of each source is identified, a decision can be made on the most suitable electricity generation technology. A local model (Ecuadorian model) is applied to calculate the potential of biogas and is compared with other models commonly used for evaluating this type of project. This type of renewable energy is attractive because it produces electricity from waste; however, it is not an attractive option unless its application is encouraged, as hydro has been encouraged through the investment of taxpayer resources. Technologies require a boost to become profitable, and even more so if they compete with traditional technologies.

Cities are human creations requiring large amounts of materials and energy. Constant consumption of resources exerts pressure on the environment not only due to its exploitation, but also because once processed, the resources produce waste, emissions or effluents. Cities are responsible for more than three quarters of the emissions of greenhouse gases. It is anticipated that the urban population will increase by up to 80% by the mid-21st century, which will make the current energy model unsustainable, as it is based on the intensive use of fossil resources. A change in urban planning is required to meet the energy requirements of cities. Several studies mention that renewable energy must be used in cities, but they do not identify the resources and technologies that can be used to promote circular urban metabolism. A review of the literature establishes that there are eleven renewable technologies with different degrees of maturity that could reduce the import of energy resources, which would contribute to changing the metabolic linear model into a circular model. However, the applicability of the different possibilities is conditional upon the availability of resources, costs, policies and community acceptance.

Previous research has assessed the potential of solar energy against possible demand; however, the sustainability issues associated with the use of large-scale photovoltaic deployment in urban areas have not been jointly established. In this paper, the impact of photovoltaic energy in the total urban energy mix is estimated using a series of indicators that consider the economic, environmental and social dimensions. These indicators have been previously applied at the country level; the main contribution of this research is applying them at the urban level to the city of Cuenca, Ecuador. Cuenca is close to the equatorial line and at a high altitude, enabling this area to reach the maximum self-supply index because of the high irradiation levels and reduced demand. The solar potential was estimated using a simple methodology that applies several indexes that were proven reliable in a local context considering this particular sun path. The results demonstrate that the solar potential can meet the electric power demand of this city, and only the indicator related to employment is positive and substantially affected. The indicators related to the price of energy, emissions and fossil fuel dependency do not change significantly, unless a fuel-to-electricity transport system conversions take place.

In situ renewable energy production is a favourable alternative for reducing pollution and combating climate change. The research area, Cuenca, Ecuador, is located in the Andes near the equator with optimal conditions for energy self-supply due to its low energy demands and low levels of irradiation variability. In this study, temporary fluctuations in consumption based on 2016 electricity consumption data are characterized. Using GIS, available roofing polygons are obtained, and the amount of usable solar radiation is estimated based on these values. With available surface, orientation, and inclination information, electricity generation based on photovoltaic performance is estimated and compared for monocrystalline silica panels and photovoltaic solar roof tiles, which are architectural alternatives. A potential net supply of 148% is found for monocrystalline silica photovoltaic panels in a typical format, whereas that of photovoltaic tiles is only 61%. In addition, production-demand imbalances are predicted in extreme months and average months and on extreme days due to variations in irradiation and demands.