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Entropy

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You are perhaps confusing entropy (a measure of the relative disorder of a system) with the relative energy in a system: A single piston sliding or a single flywheel turning on its axis is very ordered. The steam at high pressure and temperature going into that cylinder is very disordered, but may have greater energy.
 
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Your best bet is to get a Mollier diagram of the fluid of interest and study the entropy values vs pressure, temperature and fluid quality within the saturated range.
 
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[URL unfurl="true" said:
https://en.wikipedia.org/wiki/Energy_quality[/URL]]If energy A is relatively easier to convert to energy B but energy B is relatively harder to convert to energy A, then the quality of energy A is defined as being higher than that of B. The ranking of energy quality is also defined in a similar way. (T.Ohta 1994, p. 90).
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Let's be careful about the term quality in thermodynamics. In thermo, quality means the percentage by weight of vapor within a fluid(vapor and liquid mixture). In natural parlance, quality has totally different meaning.
 
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I made the statement about quality because I am not sure how much the OP knows about thermo.
 
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That figure is trying to express several different ideas at once, but in doing so, it is misleading at best, and in fact erroneous.

I think the people who made that figure showing higher entropy at lower temperatures were trying to get the following point across:

The entropy change of an object transferring heat is Q/T, where Q is the amount of thermal energy transferred to the object (negative if leaving the object), and T is the absolute temperature of the object.

Consider, for example, two large objects in thermal contact with each other, but thermodynamically isolated from the rest of the universe. The first object is at 500K, and the second object is at 200K. During some time period, 1000 kilojoules (kJ) of thermal energy is transferred from the first object to the second object.

The entropy change of the first object is -1000kJ / 500K = -2 kJ/K.

The entropy change of the second object is +1000kJ / 200K = +5 kJ/K.

(We are assuming here for simplicity that the objects are large enough ("reservoirs") that there is no significant temperature change during the transfer. This saves us from doing tricky integrals.)

So the net entropy change of the total system as a result of this heat transfer from hot to cold is +3 kJ/K. I think this idea is what led the authors to claim that entropy "increases" as temperature decreases.

But remember that we are talking about the CHANGE in entropy during a transfer across different temperatures, not the AMOUNT of entropy in an object at a given temperature.

Note that the entropy of the hot object decreases as it transfers thermal energy out (thereby lowering temperature even if only slightly) and the entropy of the cold object increases as absorbs thermal energy (thereby increasing temperature).

So the way that figure expresses the concept is not useful. You were right to be confused.
 
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