Storage Efficiency

OkwenR.T., TstewartM.T., et al. Analytical solution for estimating storage efficiency of geologic sequestration of C02. 2010 International Journal of Greenhouse Gas Control 4(1) 102-107. 

The two-dimensional (2-D) or linear ion trap (LIT) emerged in the 2000s as an effective alternative to the 3-D trap. Before 1995, linear traps were used primarily as ion storage/transfer/ion-molecule reaction devices in combination with FTICR (Senko et al., 1997 Belov et al., 2001), TOF (Collings et al., 2001), 3D ion trap (Cha et al., 2000), and triple-quadrupole (Dolnikowski et al., 1988) mass spectrometers because LITs offer better ion storage efficiencies in comparison to 3D quadrupole ion traps of the same dimensions (Hager, 2002 Schwartz et al., 2002). In 2002, commercial LITs were introduced as either stand-alone mass spectrometers (Schwartz et al., 2002) or as part of a triple quadrupole mass spectrometer (Hager, 2002). 

Figure 2. Gravimetric storage efficiency of composite cylinders (including peripherals)...

Intrinsic tests were performed on the electrolyser and fuel cell of the test bench system for their characterisation (electrical and thermal behaviour, Faraday efficiency, gas purity). Additionally simulations were performed using the Matlab/Simulink software in order to develop a numerical model for such a kind of reversible fuel cell . The system storage efficiency was estimated at 40-42%. 

Energy storage efficiency (rj) The rate of the Gibbs energy storage in an endothermic photochemical reaction divided by the incident irradiance. 

Table 21 Desorption enthalpies and hydrogen storage efficiencies...

It is not possible to give a single value for the energy storage efficiency of photosynthesis. Almost any value from 0... 

Low storage efficiency, resulting from the wasted energy needed to overcome the high enthalpy of hydride formation and elevated energy barriers to hydrogen release. 

In practice, for photochemical conversion systems, it is useful to define an overall solar energy storage efficiency... 

Fluidized beds Fluidization of the bed can result in enhanced heat and mass transfer performance. Unfortunately, many fluidized bed designs tend to be voluminous, which reduces overall storage efficiency. 

Many experimenters found how easy it is to implement such a scheme to achieve dismal efficiencies for energy storage. Efficient energy storage can... 

Reversible cell efficiency is the ratio of fuel cell to electrolysis voltage at the same cell current and hydrogen/steam feed. It is a measure of the maximum possible energy storage efficiency for a reversible system using the cell (system efficiencies will be lower than cell efficiencies). The highest reversible cell efficiency observed was 90.8% (at 925 °C and 50 mA/cm ). 

Diffusion experiments on other systems have been used to estimate the residence time of natural gas in a trapping structure (Kroos et al. 1992 Schlomer and Kroos 1997). The age of emplacement inferred from this study suggests that calculations of natural gas residence times based on these diffusion experiments seriously underestimate the storage efficiency of some trapping structures, and provide support for the viability of natural gas exploration in deeper, older, and therefore more unconventional, locations. 

The heat released during the methanol synthesis corresponds to not more than 15 % of the energy stored in the hydrogen. If, however, this heat can be fed into the reforming process, a high storage efficiency could be gained. No additional CO2 is emitted, if atmospheric CO2 is used as the carbon source. 

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