Residual biomass from guava (Psidium guajava L.), a common and widespread fruit tree native to Latin America, has been analyzed in the present research in order to determine the biomass quality and its potential use for energy purposes. Obtained biomass was grinded and compacted into the form of fuel briquettes. Determinations of solid biofuel parameters, i.e., physical, mechanical and chemical properties such as calorific value, moisture, ash content, volatile matter, mechanical durability, contents of the main chemical elements and heavy metals were performed according to international standards. As a result, not inconsiderable traces of heavy metals were found, with a concentration of zinc 4.57 mg kg⁻¹ as the highest. Guava’s moisture content (9.8%) comfortably fulfilled the minimum standard requirements and the net calorific value as received (17.11 MJ kg⁻¹) met the average value of a wood. However, measured sulphur content (0.063%) as well as ash content (3.74%) exceeded the maximum allowed limits for the graded wood briquettes and, therefore, guava wood briquettes should be rather categorized as non-woody A class briquettes. The results of the study can contribute significantly to the knowledge of guava wood properties and its potential as renewable solid fuel since there is little published data about it.

There is a growing trend toward the use of renewable sources to produce clean energy and mitigate the effects of climate change. Second-generation lignocellulose biomasses, such as agro-residues, comprise a potential energy source as a byproduct of agriculture. Ecuador has optimal climate conditions that allow for the cultivation of different types of crops. This makes agriculture a relevant economic activity in the country; however, the residues obtained from agriculture have not been investigated for the establishment of a bioenergy industry. This study evaluated the potential of three varieties of sugarcane bagasse, named PR 980, CC 85-92, and CB 40-59, for bioenergy production in the Ecuadorian Andes. The bagasse was quantified by means of weighing, and then evaluated via calorimetry and thermogravimetric analysis as well as proximal and elemental analysis. The results showed that these materials met the criteria for direct combustion, exhibiting both a low nitrogen content of 0.30 ± 0.12% and ash values of 6.20 ± 1.20%. Among the analyzed varieties, CB 40-69 stood out as the most suitable for power generation within the cogeneration system; this was attributed to its superior dry calorific value of 17.37 ± 1.45 MJ kg⁻¹, greater presence of volatile materials, and negligible ash content. Variety CB 40-69 (157.91 t ha⁻¹) reported the highest biomass and bagasse production (56.32 t ha⁻¹). Analysis of the SCB structure concluded that the three varieties did not differ significantly in their contents of lignin, hemicellulose, and cellulose, which is essential to implementing an industrial process for bioethanol production.

Building-Integrated and Building-Attached Photovoltaic (BIPV/BAPV) systems are increasingly being adopted in metropolitan areas worldwide, driven by international commitments to reduce greenhouse gas emissions and the declining cost of PV technology. A promising application involves the vertical integration of PV panels into building facades, which offers architectural and energy benefits, particularly in urban environments with limited roof space. This study experimentally evaluates the energy behavior of 12 vertically mounted 5 W PV panels (model SP005P) installed on university buildings in Ibarra, Ecuador, across four azimuth orientations (−135° SE, −45° NE, 45° NW, 135° SW). A continuous 8-month monitoring campaign was conducted using a custom-designed Arduino-based data logger, validated with multimeter measurements (error < 5%). The dataset was used to develop MATLAB version 2025b forecasting models based on Sum-of-Sine functions, achieving R² values between 0.83 and 0.98 and RMSE values between 0.024 and 0.082 W. The 45° (NW) orientation achieved the highest annual energy yield of 48% STC, reaching up to ≈440 kWh/kWp in the best-performing facade, while 135° (SW) also exhibited favorable performance compared with the northeast and southeast orientations. These findings provide significant evidence for facade-integrated PV design in equatorial latitudes, offering performance benchmarks and validated forecasting tools that can support architectural planning, BIPV feasibility analysis, and urban solar-energy strategies in regions with similar conditions.

Compendio sintético de rasgos históricos, datos geográficos, personajes representativos, instituciones educativas, expresiones culturales, gastronomía, naturaleza- producción-turismo. Retos y perspectivas para Imbabura.