Use logo of university in a presentation of work done elsewhere As a part of a PhD application process I have to give a talk about a project that I did a couple of years ago for an institution I no longer colaborate with. 

I was thinking of putting the logo of my current institution in the first of my slides as a support when introducing myself and explaining my background to the people who are going to listen to my talk.

Is this considered a good practice? I have doubts because the work I am going to talk about has no relation whatsoever with my current university.
Remember that the application process is about pitching YOU to the selection committee / other powers-that-be. Part of that pitch is introducing yourself -- and hence using your current uni logo would be appropriate. You should also explain that the work you're discussing was done elsewhere. That is, make sure anyone listening would not walk away with the wrong impression.