Wind park reliable energy production based on a hydrogen compensation system. Part I: Technical viability

Power production from renewable energy resources is increasing day by day. In the case of Spain, in 2009, it represents the 26.9% of installed power and 20.1% of energy production. Wind energy has the most important contribution of this production. Wind generators are greatly affected by the restrictive operating rules of electricity markets because, as wind is naturally variable, wind generators may have serious difficulties on submitting accurate generation schedules on a day ahead basis, and on complying with scheduled obligations. Weather forecast systems have errors in their predictions depending on wind speed. Thus, if wind energy becomes an important actor in the energy production system, these fluctuations could compromise grid stability. In this study technical and economical viability of a large scale compensation system based on hydrogen is investigated, combining wind energy production with a biomass gasification system. Combination of two systems has synergies that improve final results. In the economical study, it is considered that all hydrogen production that is not used to compensate wind energy could be sold to supply the transportation sector.Sánchez Díaz, C.; Abad, B.; Hübner, S.; Alfonso-Solar, D.; Segura Heras, I. (2011). Wind park reliable energy production based on a hydrogen compensation system. Part I: Technical viability. International Journal of Hydrogen Energy. 36(24):15548-15560. doi:10.1016/j.ijhydene.2011.09.014S1554815560362

SHORT-TERM EFFECTS OF OVARIOHYSTERECTOMY ON SOME ANTIOXIDANT PARAMETERS IN CATS

<p>This research aimed to study the short-term effect of ovariohysterectomy on oxidant/antioxidant status in healthy cats. Twenty-two female cats were allocated to the present study. All the cats were anesthetized with the xylazine-ketamine and spayed. Blood samples were collected before (D0) and three and ten days after the ovariohysterectomy to determine serum malondialdehyde, glutathione, catalase, and glutathione peroxidase concentrations. There was a statistical increase in MDA concentrations on Day 3 compared to Day 0 (p<0.05). There were no statistical differences in the MDA concentrations between Day 3 and Day 10. Catalase activity showed a remarkable increment on Day 3 compared to Day 0 and then a declination on Day 10 compared to Day 3 (p<0.05). Glutathione activity was greater on Day 3 and Day 10 compared to Day 0. Glutathione peroxidase activity was decreased on Day 3 compared to Day 0 and then increased on Day 10. Nevertheless, these increases were not significant. In conclusion, this study clearly showed that ovariohysterectomy surgery resulted in oxidative stress within the first three days after ovariohysterectomy and oxidative stress disappeared ten days after ovariohysterectomy.</p&gt