Tino Sehgal: These Associations, Tate Modern, London

Artist Tino Sehgal is photographed with participants outside Tate Modern in London. (Johnny Green)

That the electricity that crackles between people is the most powerful energy of all is an idea all too often lost, but it can be found right now at Tate Modern, in the 13th Unilever Commission by Tino Sehgal.

The Berlin-based artist, who, following training in dance and economics, became known for his artwork without objects, has emptied out the Turbine Hall save for a group of people that run or walk around the space in certain patterns. Sometimes it seems as though they are playing an abstract game – jogging at one another, chasing and dodging in a form of speeded-up group dynamics.

A teenage boy breaks off from the group and approaches me. He describes looking at himself in the mirror in T M Lewin in Canary Wharf, wearing his first suit, which he needed to join Sixth Form College. It was pale blue, and he felt he had arrived when he looked at his reflection, he says.

Another man describes the moment that he stepped off a plane from Sri Lanka to start a new life in Britain – the cold pinched his nose. A girl tells me she is upset with her sex life and is worried about the influence of internet pornography on real sex.

Are my friends just my friends because I stroke their egos, wonders another girl who breaks from the crowd to come and talk to me. Well, are they? I talk for some minutes with all of these people, sharing my own experiences or advice with them.

One can almost sense the sparks, as though we are flints striking against one another. Each one disappears back into the group. They assemble, making “shhh” noises and singing long, slow notes. They announce their presence in unison.

The lights of the Turbine Hall flicker off one by one and we are left with just their voices singing in the dark. Time is one of our greatest commodities because each of us only has a limited amount, and yet it’s the thing that many of us squander readily.

Sehgal’s artistic materials are time and attention – moments of choreographed togetherness with people, and what luxurious materials these are. The lights of the Turbine Hall flicker on again one by one as the voices rise, singing the word “electricity” over and over. They generate it as a group and with their audience. What’s powering this great old power station now?

Something dazzlingly powerful, moving, and full of potential.

To 28 October (020 7887 8888)