Formula E: Switzerland's Sebastien Buemi races to hat-trick of wins

Sebastien Buemi from Switzerland, representing Renault e.Dams, celebrates with his trophy during the FIA Formula E Championship Buenos Aires ePrix on February 18, 2016 in Buenos Aires, Argentina.???[Photo/CFP]

Defending champion Sebastien Buemi from Switzerland became the first driver to win three consecutive Formula E races after winning the Buenos Aires e Prix at the Puerto Madero Street Circuit on Sunday.

Frenchman Jean-Eric Vergne was second for the Chinese TECHEETAH team while Brazilian Lucas?di Grassi, who started in pole position, finished third for Team Abt Schaeffler Audi Sport.

The 27-year-old Renault e.Dams driver started third on the grid and led for the majority of the 37-lap race. He now leads the drivers' championship by 29 points, with Di Grassi in second.

It was Buemi's ninth win in the all-electric street racing series, and the 12th for the team.

By the time of the mandatory car change pit stop, Buemi was almost six seconds ahead and set for an easy win. But the brake balance of the second car appeared off and he struggled to slow the car in a straight line, allowing Vergne back into contention.

Renault e.Dams was concerned about one of Buemi's batteries overheating in the Argentinian heat but his energy usage figures gave no hint of a problem.

"Today, with the heat, there were many other things to manage,"said Buemi. "Especially the temperature of the battery. So at the start of the race, I took it pretty easy for a couple of laps to see where we were, and we had the pace to pass the other guys. I have to say I had everything under control and I got quite a bit of a margin."

Vergne's second-place finish was the first podium finish for the new TECHEETAH team.

Together with TECHEETAH, the NextEV NIO and Faraday Future teams are also backed by Chinese investors.

TECHEETAH is funded by China Media Capital, taking over the entry previously held by Team Aguri. In addition to Vergne, former WTCC winner Ma Qinghua races for the team.

NextEV NIO is the evolution of the team that started off as Team China Racing and carried Nelson Piquet Jr to the inaugural drivers' championship.

Faraday Future is a Chinese-backed American start-up tech company focused on the development of intelligent electric vehicles. It is set to release its first production car later this year.

DS Virgin Racing's Jose Maria Lopez, the only Argentine driver in the field, finished 10th to secure a point.

The Argentine fans also witnessed the first demonstration race of two driverless cars, 'Roborace' development, or 'DevBot', running on track at speeds of up to 185kph.

Formula E organizers hope host races of up to 10 driverless cars racing together on city tracks as a support event to their series.

"It is so exciting to see these vehicles functioning without any human intervention, making their own decisions and taking appropriate actions in order to guide themselves around the track," said Roborace chief executive Denis Sverdlov in a statement.

The Buenos Aires leg was the third FE tour leg after the Hong Kong and Marrakesh prix in 2017. The next race is in Mexico City on April 1.