Evaluación de la Eficiencia Energética del Diésel con Respecto al Gas Licuado de Petróleo (GLP), para la Generación de Energía Eléctrica en el Archipiélago de San Andrés, Providencia y Santa Catalina

Abstract

The possibility of a fuel substitution was evaluated to generate electrical energy in the archipelago of San Andrés, Providencia and Santa Catalina, since diesel is used there, which is highly polluting in terms of emissions and expensive compared to other fuels, for what is proposed is a change to LPG; The two fuels are produced in the Cartagena refinery and, being liquid, require similar logistics, transportation and infrastructure. Firstly, a theoretical review of the main properties of diesel and LPG was carried out to compare them with each other, taking as its axis the potential for generating electrical energy. In the case of LPG, it was found that its calorific value is greater than diesel in terms of in mass, but lower in terms of volume, so a greater amount of fuel is needed to produce the same amount of energy.

With the official information provided, the energy efficiency of the Bahía Garett de Providencia and Punta Evans de San Andrés electric power generation plants was found to be at an average of 32.05%; With these data, two possible fuel substitution scenarios for LPG were proposed, the first in which the energy efficiency of the system remains the same and the second if the energy efficiency were increased to 46.96% for the Punta Evans plant and 37. 71% for Bahía Garett where the number of gallons used with diesel would be equal.

Next, historical series were constructed with the purchase and freight costs of diesel and LPG, the unit cost of providing the electric energy service (CU) and the value of the service subsidies. With this information, two scenarios were carried out for the cost-benefit analysis; The first of them consisted of proposing the replacement of diesel with LPG for the generation of electrical energy and; the second, in addition to generating electrical energy with LPG, a price stabilization for the purchase of this fuel was included in the calculations, due to the volatility it presents in the market.

Based on the above, for scenario 1, more gallons of LPG are required to generate the electrical energy that the archipelago demands, however, the monthly savings in the purchase of fuel would be around COP 2,607,952,029 for the San Andrés plant. and in COP 189,768,373 for the Providencia plant. In the same way, the (CU) on average would be 190 (COP$/kWh) more economical for users of the electric energy service, if LPG were used in energy generation.

Then, the emissions of both fuels were analyzed with a comparison between the molecular components where it was observed that both have a higher proportion of carbon and in second place hydrogen; With the emission factors that were taken from the FECOC calculator established by the UPME, the emissions of CO2, CH4, N2O and SO2 were found for diesel, LPG scenario 1 and LPG scenario 2, finding that in the case of CO2, there would be a decrease of 13.3% and 36% respectively; Also, a ratio of 0.75 ton CO2/MWh would go from 0.65 ton CO2/MWh (scenario 1) and 0.48 ton CO2/MWh (scenario 2).