French driver Jean-Eric Vergne, the first double champion, is aiming to complete his title hat-trick with the Chinese-owned DS Techeetah team in a series humming with renewed energy.

The presence of four German giants, with BMW and Audi regulars already, adds luster to a city-based championship that has grown steadily since a financially precarious first season in 2014.

Formula E recently reported record revenues and a first-ever profit and, burnishing environmentally-conscious credentials with an emphasis on sustainability, feels increasingly in tune with the spirit of the times.

Nissan, Jaguar, Citroen, China's Nio and India's Mahindra are also involved.

The learning curve will be steep for the newcomers, in a championship that saw nine different winners in 13 races last season and where success costs a fraction of Formula One's bloated budgets.

"They will have done their homework. They are not starting from scratch, they have a lot of resource and clever people behind them," says Envision Virgin Racing managing director Sylvain Filippi.

"I hope they do really well, because it makes the competition even more exciting, but it's not going to be easy."

For Mercedes, the dominant force in Formula One for the past six years and the only carmaker involved in both, Formula E opens a new chapter in their 125-year racing history.

Their drivers are Belgian ex-McLaren F1 racer Stoffel Vandoorne and 2019 F2 champion Nyck de Vries of the Netherlands.

Porsche, part of the Volkswagen Group that includes Audi, have German Andre Lotterer and Swiss racer Neel Jani as their lineup.

The series reported revenues of more than 200 million euros ($221.12 million) last September and has grown to 14 races, with a first in the Indonesian capital Jakarta next June before a London finale.

Former Manchester United commercial director Jamie Reigle has joined from the NFL's Los Angeles Rams franchise, taking on the chief executive role vacated by founder Alejandro Agag.

"I genuinely believe that we have the zeitgeist in terms of one of the most compelling global sports properties with potential for income growth," he told reporters.

"I was at Heathrow (airport) the other day and there were two Formula E ads. We've done a really good job in terms of the business to the business side, brands recognizing that this is the future," he added.

"I think the task and the challenge now is 'can we get that audience to grow and be really engaged?'."

Saudi Arabia will host two races on the 22nd and 23rd in Ad Diriyah, on the outskirts of Riyadh.

The series has Liberty Global and Discovery Communications as major shareholders.

REUTERS