Energy Efficiency Factors

Furthermore, the extensive applicability of photocatalysis has essentially become a problem of energy efficiency. As a result, the quantification of these energy efficiency factors is a major issue. Thus, Chapter VI considers these factors from two perspectives quantum efficiencies and Photochemical Thermodynamic Efficiency Factor (PTEF), the latter being a new efficiency factor introduced by the authors. 

The selection of a process can be complex, requiring carehil evaluation of the many variables for each appHcation. The hemihydrate process is energy efficient, but this may not be an overriding consideration when energy is readily available from an on-site sulfuric acid plant. The energy balance in the total on-site complex may be the determining factor. 

The UPI and MI retorts are processing 7000 t/d (7700 short tons/d) of Irati shale to produce 24,381 m /d (3870 bbl) of shale as well as 80 t (55 short tons) of LPG, 132 t (145 short tons) of clean fuel gas, and 98 t (108 short tons) of sulfur. The SIX plant has reached its design rate (Table 16) in an energy efficient manner with a high on-stream (operating) factor. 

Further incentives to use energy-efficient motors are provided by various cost rebate programs offered by utilities based on norsepower rating and efficiency level. Another factor that will have a significant impact is the Energy Policy Act of 1992, in which the U.S. Congress established limits on the lowest level of nominal efficiency that certain classes of motors of standard design can have after 1997. 

For a gas turbine operating as a combined heat and power plant, the energy utilisation factor (EUF) is a better criterion of performance than the thermal efficiency. It is defined as the ratio of work output (W) plus useful heat output (Qu) to the fuel energy supplied (F),... 

Efficiency data are seasonal energy efficiency ratings (SEER) for cooling and heating seasonal performance factors (HSPF) for heating. 

Aside from the efficiency of the motor itself, energy efficiency is very dependent upon proper sizing. While the efficiency of a motor is fairly constant from full load down to half load, when a motor operates at less than 40 percent of its full load, efficiency drops considerably, since magnetic, friction, and windage losses remain fairly constant regardless of the load. Moreover, the power factor drops continuously as... 

See also Economically Efficient Energy Choices Industry and Business Energy as a Factor of Production in Industiy and Business, Productivity and Energy Efficiency in. 

The potential of mass transit to provide transportation sendees with low energy consumption relies on the high capacity of transit vehicles, since these vehicles have higher energy consumption per vehicle distance traveled compared to private motorized vehicles or nonmotorized modes. Therefore the occupancy rate of transit service is a key factor in determining its energy efficiency. This rate can be measured by the ratio of person distance traveled to vehicle distance traveled. 

Although modern chemistry allows development of even more effective rocket propellants, energy efficiency is not the only consideration factor. For example, fluorine and its derivatives arc better oxidizers than oxygen, but their extreme toxicity make them environmentally dangerous. The same concerns prevent the use of beryllium hydride—an excellent fuel that combines high density with the energy efficiency comparable to liquid hydrogen. 

Energy efficiency is one of the major factors that determines the launch vehicle layout and choice of... 

---