When calculating the COP for a heat pump, the heat output from the condenser (Q) is compared to the power supplied to the compressor (W). ... A given heat pump used for air cooling has a COP = 2 . This means that 2 kW of cooling power is achieved for each kW of power consumed by the pump's compressor.
What is pump coefficient?
The flow coefficient (φ) is a dimensionless quantity used to describe the volume flow rate . It is also referred to as the volume or volume flow coefficient and characterises the flow rate (Q). When the flow rate varies at constant rotational pump speed, vm ~ Q and therefore φ ~ Q.
How do you find the coefficient of performance?
You can calculate the coefficient of performance by dividing how much energy a system produces by the amount of energy you input into the system .
How do you calculate heat pump efficiency?
The efficiencies of air conditioners and heat pumps sold in the United States are often stated in terms of an energy efficiency ratio (EER): This peculiar ratio can be compared to the more straightforward coefficient of performance by converting BTU/hr to watts: Therefore CP = EER x 0.292.
Can the coefficient of performance of a heat pump be greater than 1?
Less work is required to move heat than for conversion into heat, and because of this, heat pumps, air conditioners and refrigeration systems can have a coefficient of performance greater than one .
What is a good coefficient of performance?
A good COP for heat pump units starts at about 2.0 for an air source heat pump and about 3.1 for geothermal, but heat pump COP can be well above 4.0 too, as seen in the chart below. A geothermal heat pump is also called a ground source heat pump.
Can coefficient of performance 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.
What is COP formula?
COP = |Q| W . COP is defined as the relationship between the power (kW) that is drawn out of the heat pump as cooling or heat, and the power (kW) that is supplied to the compressor.
Why COP of heat pump is more than refrigerator?
The heat rejected to the hot sink is greater than the heat absorbed from the cold source , so the heating COP is 1 greater than the cooling COP. applies to heat pumps and applies to air conditioners or refrigerators.
Why COP is used instead of efficiency?
the purpose of using heat engine is to produce work by the heat gained from the hot source. the efficiency expresses how much work has been produced from a unit of heat gained from the hot source. ... so the efficiency in this case is the heat removed from the cold place per unit of work applied (which is called COP).
What is the maximum coefficient of performance of the heat pump?
Plugging the temperature in the COP cooling equation above, we get 7.8. If you remember, the maximum coefficient of performance of a heat pump was 8.8 . If you are in the market for an air conditioner, make sure to get one with a COP value of above 2. That's a very high COP for a practical HVAC cooling device.
What is the correct formula for calculating COP of heat pump?
COPHP = (Desired Output)/(Required Input) = (Heating Effect)/(Work Input) = QH/Wnet,in = 1 + (QL/Wnet,in) Both the COP of a refrigerator and a heat pump can be greater than one.
How do heat pumps have over 100% efficiency?
By contrast, heat pumps seemingly undertake the impossible: you get more heating out than the energy you put in . This is possible because we are using energy to move heat – rather than converting the energy directly to heat. As a result the apparent efficiency in terms of heat output is greater than 100%.
What is the coefficient of performance of this refrigerator?
For a refrigerator keeping an inside temperature of 4 o C = 277 K operating in a room at 22 o C = 299 K the best possible coefficient of performance is COP max = 277/(299 – 277) = 12.6 . The best possible ratio of the amount of heat removed to the work done is 12.6.
Do you think efficiency can exceed 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).
What if COP is less than 1?
Coefficient Of Performance (COP) is the ratio of “Coldness” produced to the “Heat” or ” Work” supplied. In the case of vapour compression system, it is the mechanical or electrical work , which is the Input to the machine. ... But if COP is less than 1 for VCRS system then it will not be feasible to run the system .
