From the normal consumption of energy, it is inherently impossible to maintain the efficiency of any machine or device to 100% or even higher than 100%. Energy utility efficiencies are usually below 100%, and occasionally they are much less than 90%. The implication of this is that the energy output exceeds the energy input. The output is commonly less than the input energy because of the loss of useful energy to the environment. Maintaining a 100%, efficiency would demand that all possible measures be taken to prevent the loss or energy. The challenge is that any external component of the machine absorbs the energy in various forms, leaving a residual value slightly less than 100%.
In general, energy transformation efficiency is a dimensionless value in the range between 0.0 and 1.0. This is the same as between 0.0% – 100.00% (Lee, Jadhav & Baldo, 2009). The practical findings by many engineers and scholars are that efficiencies do not surpass 100%. For example, a machine in continuous motion consumes more energy than it produces. Nonetheless, other machines have effectiveness going beyond 100%, and are used to heat pumps and many other devices moving heat instead of converting it.
Concerning the efficiency of machine engines in power stations, the variation in energy have to be specified clearly, which is inclusive of the Gross Heating Value or the Net Heating index, and the concern over the gross energy output at the terminal of the generator or the net power station yield are being measured.
The European approach to the computation of energy consumption for the fuel is classically by use of the lower heating value (LHV) for the fuel, assumes by definition that the energy output in combustion is not condensed to and does not form LHV (latent heat of vaporization). With the latent heat of vaporization, a condensing boiler may attain energy efficiency greater than 100% without necessarily going against the principal law of thermodynamics, with a proper understanding of the latent heat of vaporization convention, and without any contradiction. The reason for generation of efficiency above 100% is that the machine or the equipment used retrieves part of the heat during evaporation, and is not taken into consideration when defining the lower heat value for the burning fuel. The approach for calculation is different in the U.S. and other parts as they use the HHV (higher heat value). This according to Monestier et al (2007) includes the latent heat for the condensation of water vapor, causing the highest thermodynamic efficiency of 100% efficiency but cannot exceed 100% because of the HHV used (Green, 2009).
Energy Efficiency is commonly confused with energy consumption effectiveness. Any system that wastes greater part of its input energy and yields exactly the same amount it is expected to generate is effective but is not necessarily energy efficient. The terminology “energy efficiency” is significant only in situation to the required influence. Using an example of a bulb, the bulb may have an efficiency of 2% but still the efficiency is 98% efficient in heating its location (Matar, 2015). Practically, its efficiency is almost 100% in heating its environment as the light energy is ultimately changed into heat. Still, part of the output energy is lost via the windows. Electric kettle possibly attains the threshold of 100% efficiency; relatively less heat energy is consumed in the 3 minutes in which the kettle boils the water.
Exceptional energy efficiency is also found in electric motor with more than 90%, referred to as premium energy efficiency. Kyba, Hänel & Hölker (2014) argues that large power transformer applied in the electrical grid can have energy efficiency of 100% and above, unlike the earlier transformers that wasted about 34% of the energy input that passed through them.
Because of the highest power hypothesis, the device allows passage of the highest power to the load while flowing at an electricity energy efficiency of 50%. This happens while the device load resistance equals the interior resistance. The validity of this system only prevails for non-reactive energy source and load impedances.
Interestingly, the power plants from where much energy yield is expected to emerge, the energy efficiency is between 35% and 40%, while the efficiencies of devices that consume the yield energy are above 65% (Semonin et al, 2011). The energy conversion process must reduce the energy loss through the equipment and in the environment for the energy efficiency to reach 100% and above.
In the thermodynamic laws, the potential efficiency of energy consumption and production can not be 100% or worse still, above 100%. Machines cannot generate more energy than they consume. However, there are claims about LED having 8000% efficiency and enabling data transmission at extremely less power. If the claims are true, then the laws of Thermodynamics ought to be revised.
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