Paola Helena Barros Zarante

Status of non-conventional sources of energy in Colombia: a look at the challenges and opportunities of the electric sector

This article analyzes the current state of Colombias energy matrix, analyzing aspects of energy policy, the current state of non-conventional sources of energy (NCSE), the challenges and opportunities that the country is having in order to promote the implementation and use of this type of energy as well as the existing barriers to it. It is known that the Colombian electricity sector is in a constant challenge, which has led the national government to look for new alternatives to face the increase in electricity demand through the NCSE, sanctioning Law 1715 of 2014, to leave the dependence on fossil fuels to produce electricity, as well as the generation of hydraulic energy that is affected by the climatic variability of the country. With the new normative guidelines of the electricity sector, the government intends to deal with Greenhouse Gas (GHG) emissions and reach the non-interconnected areas by generating energy from renewable sources, which allows the diversification of the national energy matrix and therefore guaranteed the energy supply in a sustainable and environmentally friendly way.

Cracking force estimation for Lecythis minor medicinal nuts

Lecythis minor are medicinal nuts used for obtaining Selenium, an important element for the immunologic system of the human body. This paper presents the statistical procedure for setting a usual (p-value 0.05) interval for the Lecythis Minor nutshell cracking force, so that the nut is separated from the nutshell. Analyzed data was obtained from the software of a SHIMADZU AG-X Plus machine, where the compression test was performed on sample of 25 nuts. Chauvenet ́s outlier detection method was recursively applied until a data set of 22 nuts showed no outliers. No previous literature reporting the cracking force for this nut is found. This work is very useful for design engineers since a realistic load value can be assigned to simulations and calculations of nutcracker machines.

Simulation of Aldehyde Emissions from an Ethanol Fueled Spark Ignition Engine and Comparison with FTIR Measurements

This paper presents a mathematical model that calculates aldehyde emissions in the exhaust of a spark ignition engine fueled with ethanol. The numerical model for aldehyde emissions was developed using FORTRAN software, with the input data obtained from a dedicated engine cycle simulation software, AVL BOOST. The model calculates formaldehyde and acetaldehyde emissions, formed from the partial oxidation of methane, ethane and unburned ethanol. The calculated values were compared with experimental data obtained by Fourier Transform Infrared Spectroscopy (FTIR). The experiments were performed with a mid-size sedan powered by a 1.4-liter spark ignition engine on a chassis dynamometer. In general, the results demonstrate that the concentrations of aldehydes and the source elements increased with engine speed and exhaust gas temperature. A reasonable agreement between simulated and measured values was achieved.