Análisis técnico, económico y ambiental para la sustitución de combustible fósil en la planta de producción de asfalto del GAD Municipal de Cuenca mediante la implementación de un sistema de colectores cilindro parabólico

Abstract

The present work evaluates the technical, economic and environmental feasibility of implementing a parabolic trough collectors (PTCs) system to generate heat in an asphalt plant in Cuenca, Ecuador. The proposal includes the use of an available land of 1.200 m2 in which the PTCs will be installed. To decide on the type of PTC, different systems were simulated in SAM (System Advisor Model) using the commercial models PTC 1800, Power Trough 250, Solar Wing EVO and Vicot. The performance of the four systems were compared with each other and the levelized cost of heat (LCOH) was used as an indicator to select the system with the lowest power generation cost. With the selected system, the economic benefits and emission reductions were analyzed considering that the conventional asphalt cement heating system (with amortized boiler) operates with a diesel boiler in a base scenario and with a fuel oil boiler in an alternative scenario. The results show that, of the systems analyzed, the one that generates energy at a lower cost is the Vicot PTC system (0,082 USD/kWht). This system with an aperture area of 390 m2

is capable of achieving an annual solar fraction of 31%. In the base scenario, the installation of the Vicot PTC system is economically viable, since under these conditions it was possible to obtain a net present value (NPV) of USD 21.274 and a discounted payback period of 8,89 years. In addition, in this scenario, the system would avoid the consumption of 5.698 gallons of diesel per year and the emission of 49,4 tCO2/year. On the contrary, in the alternative scenario, the possibility of installing the PTC system is not feasible, since the low price of fuel oil prevents recovering the invested capital and obtaining profits in the future.