ABSTRACT
RESUMEN El incremento en el precio de los combustibles fósiles y los problemas de contaminación derivados de su quema, han provocado la intensificación del aprovechamiento de las energías renovables para producir energía eléctrica. El objetivo de este estudio fue estimar el desarrollo de las energías renovables solar-fotovoltaica y eólica en la generación de energía eléctrica, comparándola con la producida con combustibles fósiles. Se consultaron varios reportes, emitidos por organismos gubernamentales y no gubernamentales, sobre el consumo energético mundial, para producir energía eléctrica a base de combustibles fósiles y de energías renovables, sobre la problemática del cambio climático y las políticas establecidas para incorporar energías renovables en el portafolio energético mundial. Los resultados indicaron que las plantas de generación de energía eléctrica, a partir de energía eólica y solar-fotovoltaica, son competitivas respecto a las plantas que utilizan recursos fósiles. A corto plazo, se esperan leyes regulatorias, con sanciones por contaminación, para limitar los efectos en el cambio climático, lo que elevará el costo de producción de las plantas convencionales, favoreciendo el desarrollo de las plantas de energías renovables, principalmente la solar-fotovoltaica, la cual tiene el mayor crecimiento de las energías renovables.
ABSTRACT The increase in the price of fossil fuels and the pollution problems arising from their burning has resulted in the intensification of the use of renewable energy sources to produce electricity. The purpose of this study was to estimate the development of solar photovoltaic and wind energy in electricity generation, compared to the generation produced with fossil fuels. Several reports issued by governmental and non-governmental bodies on global energy consumption to produce electricity from fossil fuels and from renewable energy sources, on climate change and on poli cies to incorporate renewable energy sources in the global energy portfolio were consulted. The results indicated that electric power from wind and solar photovoltaic energy generation plants are competitive with respect to the plants that use fossil resources. In the short run, regulatory laws that include pollution-related sanctions to limit the effects on climate change are expected to emerge. Such laws are likely to raise the cost of production of conventional plants, while favoring the development of renewable energy plants, mainly solar photovoltaic, which has the fastest growing renewable energy.
ABSTRACT
The secondary metabolites, phenazine products, produced by Pseudomonas aeruginosa can mediate the electrons transfer in microbial fuel cells (MFCs). How increase the total electricity production in MFCs by improving the characteristics of Pseudomonas aeruginosa is one of research hot spots and problems. In this study, P. aeruginosa strain SJTD-1 and its knockout mutant strain SJTD-1 (ΔmvaT) were used to construct MFCs, and the discharge processes of the two MFCs were analyzed to determine the key factors to electricity yields. Results indicated that not only phenazine but also the viable cells in the fermentation broth were essential for the discharge of MFCs. The mutant strain SJTD-1 (ΔmvaT) could produce more phenazine products and continue discharging over 160 hours in MFCs, more than that of the wild-type SJTD-1 strain (90 hours discharging time). The total electricity generated by SJTD-1 (ΔmvaT) strain could achieve 2.32 J in the fermentation process, much higher than the total 1.30 J electricity of the wild-type SJTD-1 strain. Further cell growth analysis showed that the mutant strain SJTD-1 (ΔmvaT) could keep a longer stationary period, survive much longer in MFCs and therefore, discharge more electron than those of the wild-type SJTD-1 strain. Therefore, the cell survival elongation of P. aeruginosa in MFCs could enhance its discharging time and improve the overall energy yield. This work could give a clue to improve the characteristics of MFCs using genetic engineering strain, and could promote related application studies on MFCs.