Energy flows under human control: energy input, power capacity and human labour

Author(s):  
Aaron K. Townsend ◽  
Michael E. Webber

An optimization model was created to optimize the input power capacity and storage capacity relative to the output power capacity of a compressed air energy storage (CAES) facility in the Electric Reliability Council of Texas (ERCOT) grid. Historical electricity and non-spinning reserve prices were used to calculate the economic feasibility of CAES in each of the zones in ERCOT. The analysis found that with perfect knowledge of future prices a CAES facility would be economically attractive over the period of years considered, and the non-spinning reserve ancillary service market provided a substantial contribution to the overall revenue of the facility. Optimal input power capacity for the entire period of 2002 through 2010 was found to be about one-quarter of the output capacity in the Houston, South, and North zones in ERCOT and one-half the output power capacity in the West zone in ERCOT. Optimal storage capacity was found to be about 17 hours in the Houston, South, and North zones and 31 hours in the West zone. Optimal values for individual years varied significantly, as did revenues. The negative electricity prices that have occurred historically in the West zone are the consequence of wind generators and lack of transmission capacity to export electricity; this effect gives CAES greater opportunity to perform price arbitrage and improves the economics of such a facility.


Author(s):  
David W. Piston ◽  
Brian D. Bennett ◽  
Robert G. Summers

Two-photon excitation microscopy (TPEM) provides attractive advantages over confocal microscopy for three-dimensionally resolved fluorescence imaging and photochemistry. Two-photon excitation arises from the simultaneous absorption of two photons in a single quantitized event whose probability is proportional to the square of the instantaneous intensity. For example, two red photons can cause the transition to an excited electronic state normally reached by absorption in the ultraviolet. In practice, two-photon excitation is made possible by the very high local instantaneous intensity provided by a combination of diffraction-limited focusing of a single laser beam in the microscope and the temporal concentration of 100 femtosecond pulses generated by a mode-locked laser. Resultant peak excitation intensities are 106 times greater than the CW intensities used in confocal microscopy, but the pulse duty cycle of 10-5 maintains the average input power on the order of 10 mW, only slightly greater than the power normally used in confocal microscopy.


Author(s):  
David W. Piston

Two-photon excitation fluorescence microscopy provides attractive advantages over confocal microscopy for three-dimensionally resolved fluorescence imaging. Two-photon excitation arises from the simultaneous absorption of two photons in a single quantitized event whose probability is proportional to the square of the instantaneous intensity. For example, two red photons can cause the transition to an excited electronic state normally reached by absorption in the ultraviolet. In our fluorescence experiments, the final excited state is the same singlet state that is populated during a conventional fluorescence experiment. Thus, the fluorophore exhibits the same emission properties (e.g. wavelength shifts, environmental sensitivity) used in typical biological microscopy studies. In practice, two-photon excitation is made possible by the very high local instantaneous intensity provided by a combination of diffraction-limited focusing of a single laser beam in the microscope and the temporal concentration of 100 femtosecond pulses generated by a mode-locked laser. Resultant peak excitation intensities are 106 times greater than the CW intensities used in confocal microscopy, but the pulse duty cycle of 10−5 maintains the average input power on the order of 10 mW, only slightly greater than the power normally used in confocal microscopy.


2020 ◽  
Vol 26 (3) ◽  
pp. 14-19
Author(s):  
Laurențiu Bogdan Asalomia ◽  
Gheorghe Samoilescu

AbstractThe paper analyzes, starting from the Integrated Management System, the role of automation, the role of the officer and the role of the Energy Management System on board the ship. The implementation of an EnMS establishes the structure and discipline of identifying energy flows, implementing management actions and, finally, applying technical solutions, which significantly reduce energy costs, reduce non-productive time in production, and reduce emissions. of Greenhouse Gases in the environment. The steps to be highlighted in the realization of energy management are analyzed.


2018 ◽  
pp. 15-27 ◽  
Author(s):  
V. A. Gribkov ◽  
◽  
A. S. Demin ◽  
N. A. Epifanov ◽  
E. E. Kazilin ◽  
...  

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