Can you have an efficiency greater than 1? Since a machine does not contain a source of energy, nor can it store energy, from conservation of energy the power output of a machine can never be greater than its input, so the efficiency can never be greater than 1 .
Can pump efficiency be greater than 1?
It’s Coefficient of Performance (the term used instead of efficiency) is normally greater than 1 and does not violate the laws of thermodynamics.
Can you have a heat engine with efficiency greater than 1?
The efficiency of a heat engine is the work we can do divided by the heat we take out of the hot reservoir. This quantity is always ≤1 .
Can efficiency be more than 100%?
Due to the conservation of energy, P can never be greater than C, and so the efficiency r is never greater than 100% (and in fact must be even less at finite temperatures).
Can there be 100% efficiency?
Efficiency is the percent of work put into a machine by the user (input work) that becomes work done by the machine (output work). The output work is always less than the input work because some of the input work is used to overcome friction. Therefore, efficiency is always less than 100 percent .
Can efficiency of refrigerator be greater than 1?
If you analyze a refrigerator as a closed system and measure the changes in temperature and entropy in both high temperature and low temperature recipients you will realize that its efficiency is not greater than one .
How can COP be greater than 1?
The COP usually exceeds 1, especially in heat pumps, because, instead of just converting work to heat (which, if 100% efficient, would be a COP of 1), it pumps additional heat from a heat source to where the heat is required . Most air conditioners have a COP of 2.3 to 3.5.
Why is efficiency less than 1?
Since a machine does not contain a source of energy, nor can it store energy, from conservation of energy the power output of a machine can never be greater than its input , so the efficiency can never be greater than 1.
Why is 100 efficiency impossible?
It is impossible for heat engines to achieve 100% thermal efficiency () according to the Second law of thermodynamics. This is impossible because some waste heat is always produced produced in a heat engine , shown in Figure 1 by the term.
Why is thermal efficiency less than 1?
When expressed as a percentage, the thermal efficiency must be between 0% and 100%. Efficiency must be less than 100% because there are inefficiencies such as friction and heat loss that convert the energy into alternative forms .
Can a boiler be 100% efficient?
Boiler efficiency can be defined as the ratio of the useful heat output to the total energy input. Typical boiler efficiencies range from about 90% for the best solid biomass fuel boilers to close to 95% for oil- and natural gas-fired boilers , Table 3.2.
Can boiler efficiency be more than 100%?
The efficiency of modern condensing gas boiler can be over 100% as heat is extracted from the incoming air. A traditional brick built coal fired boiler may only be 50% efficient.
What is the value of efficiency?
Summary. Herein, we introduce the value of efficiency (VOE)— a metric defining the allowable cost for innovation by analyzing the co-dependence of levelized cost of electricity (LCOE) on manufacturing cost and efficiency . Historically, VOE values have dropped rapidly and will further, yet slower, decline in the future.
What is the highest efficiency machine?
Believe it not, the bicycle is the most efficient transport machine ever invented. You can go farther for the same amount of energy on a bike than you can with any other means of transport. A bicycle goes 3,000 miles on the energy equivalent of one gallon of gasoline.
What energy system is 100% efficient?
Electric resistance heating is 100% energy efficient in the sense that all the incoming electric energy is converted to heat. However, most electricity is produced from coal, gas, or oil generators that convert only about 30% of the fuel’s energy into electricity.
Can you design an engine of 100 efficiency?
That is, it is not possible to design a heat engine that does not exhaust heat to the environment. Or, it is not possible to design a heat engine that has an efficiency of 1.00 or 100% . The efficiency of a heat engine can be 100% only if all the heat energy gets converted into work (or mechanical energy).
Can a refrigerator COP be greater than 1?
COP of refriegeration is always greater than one . The coefficient of performance (COP) of refrigeration is always more than 1. Hence option (a) is correct. COP is the ratio of heat extracted from the refrigerator to the work done on the refrigerant.
Can a COP be less than 1 in a refrigerator?
Generally, T1 and T2 difference is less than T2 so efficiency is always greater than 1. Hence the correct answer is option (A). Thus, we can say that the COP of the refrigerator and air-conditioner can be less than one or greater than one .
Can the value of thermal efficiency be greater than 1 Why or why not?
Can the value of thermal efficiency be greater than 1? Why or why not? No , according to the first law of thermodynamics, energy output can never be more than the energy input.
Can the COP of a heat pump be less than 1?
Relation between COP of Heat Pump and Refrigerator
The COP of the refrigerator and air-conditioner can be less than one or greater than one. The above formula also shows that the COP of the heat pump can never be less than one ; it is always more than one.
What is difference between efficiency and COP?
Efficiency is a dimensionless obtained by dividing two quantities of same units. The Coefficient of Performance (COP) can depend on numerous other variables and can be used to easily compare the performance of two different units, or the same unit under different conditions.
Can the COP be greater than unity?
Coefficient of Performance (COP)
The pragmatic definition of the COP is: COP = (What you Get)/(What you Pay For). This measure of performance can have a value greater than unity , and it is this fact that makes a heat pump an attractive device.
Why is the efficiency of machines always less than 1 or 100?
The percentage of the work input that becomes work output is the efficiency of a machine. Because there is always some friction , the efficiency of any machine is always less than 100 percent.
Why is the efficiency of Carnot engine less than 1?
1. η is always less than 1 because TL is less than TH . This implies the efficiency cannot be 100%. It can be 1 or 100% only when TL = 0K (absolute zero of temperature) which is impossible to attain practically.
Can efficiency of machine be greater than unity?
In an ideal machine, efficiency is 100% or unity so the mechanical advantage is equal to the velocity ratio. In the actual machine: efficiency is less than 1.
Is it possible to build a Carnot engine?
Carnots engine cannot be real because 100% efficiency cannot be obtained in real life. This is because, to achieve 100% efficiency in Carnot’s engine the temperature of the sink must be as least as possible. The least possible temperature we can think of is 0 kelvin.
Which law of thermodynamics says that efficiency of a heat engine Cannot be 1?
Which law of thermodynamics says that efficiency of a heat engine cannot be 1? Explanation: The second law of thermodynamics fundamentally disallows many processes that may be consistent with the law of conservation of energy. It says that entropy change in an irreversible process has to be positive.
How efficient is an F1 engine?
F1 regulations have had a massive push towards fuel efficiency in recent years. The 2020 Mercedes engine is now over 50% thermal efficient , meaning that over half of the energy in the fuel is used to propel the car, which is an increase from around 44% in 2014 when these engines were introduced.
Why is heat engine is not 100% efficient?
What is ideal efficiency?
It is known that an engine with ideal efficiency ( eta =1 for a chemical engine and e = e_{rm Carnot} for a thermal one ) has zero power because a reversible cycle takes an infinite time.
How efficient can a boiler be?
Generally, conventional boilers can only reach 70-80% efficiency. These high-efficiency boilers owe a great deal of their heat conversion to their combustion chamber.
How efficient is a 25 year old boiler?
What is a good efficiency for a boiler?
Replacing Your Furnace or Boiler
Although older fossil fuel furnace and boiler systems have efficiencies in the range of 56% to 70% , modern conventional heating systems can achieve efficiencies as high as 98.5%, converting nearly all the fuel to useful heat for your home.
What is the maximum pump efficiency?
Many medium and larger centrifugal pumps offer efficiencies of 75 to 93 percent and even the smaller ones usually fall into the 50 to 70 percent range. Large AC motors, on the other hand, approach an efficiency of 97 percent, and any motor—ten horsepower and above—can be designed to break the 90 percent barrier.
What is the efficiency of a pump?
Pump efficiency is defined as the ratio of useful hydraulic power delivered to the fluid to the power input at the drive shaft .
Which pump has high efficiency?
Where different pump designs could be used, the centrifugal pump is generally the most economical followed by rotary and reciprocating pumps. Although, positive displacement pumps are generally more efficient than centrifugal pumps, the benefit of higher efficiency tends to be offset by increased maintenance costs.
