Net energy value

The energy value of feeds is expressed in UFC. This energy unit corresponds to the net energy value of one kilogramme (as fed) of a reference barley, used for maintenance in the horse (INRA, 1984 andVermorel and Martin-Rosset, 1997). 

Persson, T., Garcia y Garcia, A., Paz, J., Jones, J., Hoogenboom, G. (2009). Maize ethanol feedstock production and net energy value as affected by climate variability and crop management practices. Agncittora/Syrfemj, 100, 11—21. 

The French system provides tables of net energy values of some 149 foods for maintenance, which are considered applicable to lactation as well. The values are stated in terms of UFC (unite fouragere cheval) one UFC is equal to the net energy of standard barley, equal to 9.42 MJ/kg. 

Trace element and vitamin content assumes a net energy value of 9.4 MJ/kg. Intermediate-type pig. 

Andrew, S.M., H.F. Tyrrell, C.K. Reynolds and R.A. Erdman, 1991. Net energy value for lactation of a dietary fat, calcium salts of long chain fatty acids, for cows fed silage based diets. J. Dairy Sci. 74,2588-2600. 

Lofgreen, G.R, 1965. A comparative slaughter technique for determining net energy values with beef cattle. In Proceedings of Energy Metabolism, 3, Troon. Academic Press 309-317. 

Noblet, J, H. Eortime, X.S. Shi and S. Dubois, 1994a Prediction of net energy value of feeds for growing pigs.J. Anim. Sci 72, 344-354. 

Artificial lift techniques are discussed in Section 9.6. During production, the operating conditions of any artificial lift technique will be optimised with the objective of maximising production. For example, the optimum gas-liquid ratio will be applied for gas lifting, possibly using computer assisted operations (CAO) as discussed in Section 11.2. Artificial lift may not be installed from the beginning of a development, but at the point where the natural drive energy of the reservoir has reduced. The implementation of artificial lift will be justified, like any other incremental project, on the basis of a positive net present value (see Section 13.4). 

Capital investment decisions are best made within the context of a life-cycle cost analysis. Life-cycle cost analysis focuses on the costs incurred over the life of the investment, assuming only candidate investments are considered that meet minimally acceptable performance standards in terms of the non-inonetary impacts of the investment. Using life-cycle analysis, the capital investment decision takes into account not just the initial acquisition or purchase cost, but maintenance, energy use, the expected life of the investment, and the opportunity cost of capital. When revenue considerations are prominent, an alternative method of analysis such as net benefit or net present value may be preferred. 

The efficient heat pump reduces energy use by 1,676 kWh per year on average. Is the efficient model heat pump a good investment Suppose the incremental cost of the efficient unit, as compared with the less efficient unit, is 1,000, and electricity cost 10 cents per kWh. With this price of electricity, the efficient heat pump reduces electricity costs by 167.60 per year. Taking a simplified approach for purposes of illustration and assuming that each unit lasts indefinitely and has no repair, maintenance, or replacement costs, and ignoring possible tax effects, the internal rate of return may be calculated as 1,000= 167.60/r, which is 16.76 percent per year. If the household can borrow money at, say, 10 percent per year and earn 16.76 percent, the investment makes economic sense. If we assume a 10 percent discount rate, the present value of the investment is 1,676, which exceeds the initial investment cost. The net present value is 676, which indicates that the investment is feasible. 

An energy-level diagram demonstrates that the net energy change for a chemical reaction (A S ) has the same value regardless of the path used to accomplish the reaction. 

In the denominator, the first term in the braces is the net energy above the minimum value to sustain the flame and the second term in the braces is the net heat flux to the fuel. Both of these terms must be positive for a valid physical solution. 

Temperature Oxygen at Net energy Calorific value Energy in gas... 

A comparison of husD and fe/M/t) values for sample 3 are particularly instructive. The heat values for the immersion of monolayer-covered samples in toluene, cyclohexane, and carbon tetrachloride are three to four times less than the heat values for the bare samples and are also significantly less than the surface enthalpies of the respective liquids. Apparently, the attractive forces of the covalent carbon atoms in the surface are highly localized. In addition, the interaction of first-layer molecules with those in the second layer is less than between the liquid molecules in adsorbed monolayer, as indicated by the 7 s (14)- The net energy of adsorption... 

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