I don't know how I got "mysterious energy" in a Carnot heat pump

AI Thread Summary
The discussion centers on the operation of a Carnot heat pump and the apparent paradox of how the heat delivered to the hot reservoir (Q_H) can exceed the work input (W). The equations derived show that Q_H equals W multiplied by (K + 1), where K is the efficiency coefficient. This indicates that the heat pump utilizes energy from both the work input and the heat extracted from the cold reservoir. Participants clarify that the Carnot cycle allows for this efficiency by leveraging energy from the cold reservoir, enabling greater heating than direct energy conversion. The conversation emphasizes the role of the Carnot cycle in achieving this effect.
Philip Robotic
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Homework Statement
Calculate the heat Q_H that a Carnot heat pump can deliver to the reservoir with a temperature T_H. Temperature of lower reservoir (T_L) and work (W, W>0) are given
Relevant Equations
Equations come from Carnot refrigeration cycle
1. |W|=|Q_H|-|Q_L|
2. K=|Q_L|/|W|
So first I transformed the equation no 2 like this:
$$|Q_L|=K\cdot|W|$$
And then I transformed the first equation to find ##|Q_Z|##
$$|Q_L|=|Q_H|-|W|$$
Plugging the result into the first equation
$$|Q_H|=K\cdot |W|+|W|$$
$$|Q_H|=|W|\cdot (K+1)$$
We know that the efficiency coefficient K is greater than 0, so how is it possible that the energy "pumped" into the hot reservoir (##Q_H##) is greater than the work that was put into the system?
 
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Philip Robotic said:
Homework Statement: Calculate the heat Q_H that a Carnot heat pump can deliver to the reservoir with a temperature T_H. Temperature of lower reservoir (T_L) and work (W, W>0) are given
Homework Equations: Equations come from Carnot refrigeration cycle
1. |W|=|Q_H|-|Q_L|
2. K=|Q_L|/|W|

So first I transformed the equation no 2 like this:
$$|Q_L|=K\cdot|W|$$
And then I transformed the first equation to find ##|Q_Z|##
$$|Q_L|=|Q_H|-|W|$$
Plugging the result into the first equation
$$|Q_H|=K\cdot |W|+|W|$$
$$|Q_H|=|W|\cdot (K+1)$$
We know that the efficiency coefficient K is greater than 0, so how is it possible that the energy "pumped" into the hot reservoir (##Q_H##) is greater than the work that was put into the system?
The heat to the hot reservoir is the work that was put into the system plus the heat that is pumped from the cold reservoir.
 
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So I will be able to heat up a certain substance more by using a Carnot Heat Pump than by theoretically converting all the available energy to heat? Do I understand it correctly?
 
Philip Robotic said:
So I will be able to heat up a certain substance more by using a Carnot Heat Pump than by theoretically converting all the available energy to heat? Do I understand it correctly?
There is also energy available from the cold reservoir, and you’re using some of that too.
 
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Did you use the information that it is a Carnot cycle?
 
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