A non-conservative force (pressure) emerges when water is placed in an electric field:

http://electron6.phys.utk.edu/Physic...electrics.html
"A plane capacitor with rectangular plates is fixed in a vertical position.. [...] The capacitor is charged and disconnected from the battery. [...] The lower part of the capacitor is now brought into contact with a dielectric liquid:

http://electron6.phys.utk.edu/Physic...ges/Image4.gif

When the plates contact the liquid's surface, a force in the upward direction is exerted on the dielectric liquid. The total charge on each plate remains constant and there is no energy transferred to the system from outside.." [END OF QUOTATION]

There IS energy transferred to the system from outside - the rising water can do work, e.g. by lifting a floating weight - and this energy can only be AMBIENT HEAT.

What is the molecular mechanism behind the effect? Here is a schematic presentation of water dipoles in the electrical field:

http://www.gsjournal.net/old/valev/val2.gif

If it were not for the indicated (with an arrow) dipole, other dipoles in the picture are perfectly polarized as if there were no thermal motion. Of course, this is an oversimplification – thermal motion is a factor which constantly disturbs the polarization order. The crucial point is that, as can be inferred from the picture, any thermal disturbance contributes to the creation of a pressure between the plates. Consider the indicated dipole. It has just received a strong thermal stroke and undergone rotation. As a result, it pushes adjacent dipoles electrostatically, towards the plates. Macroscopically, the sum of all such disturbances is expressed as a pressure exerted on the plates. One can also say, somewhat figuratively, that the indicated dipole has absorbed heat and now, by pushing adjacent dipoles, is trying to convert it into work.

Pentcho Valev