Entropy Engine

[abv]

Interesting concept, but you would need some calculations of the heat released during magnetization, and the temperature rise of the material and the surrounding working fluid. I don't think you get much at all.

More information about this has been added to site:
https://somephysicsideas.wordpress.com/2016/02/13/entropy-engine/

[pomodoro]

How much energy is required to pull the gadolinium out of the field?

[lumen]

How much energy is required to pull the gadolinium out of the field?

What is the difference between the pull into and then ,after cooling to ambient, back out of the field.

To show the work applied for the work done. The magnothermal effect is surly not free.

[abv]

How much energy is required to pull the gadolinium out of the field?

Above Curie point (293K) the Gadolinium is paramagnetic.
https://en.wikipedia.org/wiki/Paramagnetism

[abv]

What is the difference between the pull into and then ,after cooling to ambient, back out of the field.

To show the work applied for the work done. The magnothermal effect is surly not free.

Nothing free.
The magnetic field is not free. It came from rotation of unpaired electrons in parallel domains. These electrons have an energy.
Main idea of magnetocaloric effect is the magnetic field polarizes the magnetic spins of electron and increases temperature of substance. Vice versa, without magnetic field the temperature goes down from free fluctuations of magnetic spins of electrons.