Sauber Formula 1 team considered also entering Formula E

Formula E's third season begins in Hong Kong this weekend, days after F1 world champion team Mercedes announced that it has secured an entry for the 2018/19 season.

It has emerged a slot on the grid for the first season in 2014/15 was held for Sauber before the Swiss team decided against adding the programme, so that it could focus on its F1 effort.

When asked by Autosport how seriously it considered the entry, Kaltenborn said: "We were very, very serious about it.

"It's something we looked at right at the beginning and right to the end they kept a seat for us, but we had other issues to sort out and you don't want a new one coming up.

"We were on to it for a long time, since the time when they started talking about it.

"We were really into it but if the time is not right, one shouldn't force it."

Kaltenborn said there is the option to enter the championship in the future, particularly because she believes in the concept.

It also ties in with Sauber wanting to expand its third-party business after taking on new owners earlier this year.

"We will continue to look at it carefully, the door is not closed there for me, but it's an add-on," she said.

"Definitely, it's something one should look at. It's the future. We are diversifying.

"Were you allowed to work on the chassis, we could do that quickly as we have a track record in doing things for other series.

"It was logical step to consider, if you can do this and increase your portfolio of activities you're involved in, why not?"

Mercedes follows Jaguar into Formula E, with BMW having confirmed an engineering partnership with Andretti and Audi upping its involved in Abt, while Renault and Citroen's DS brand are also on the grid.

Kaltenborn said it will be interesting to see how the championship evolves following the influx of manufacturers.

"If you see Formula E, the teams which started, a few of them aren't there," she said.

"It started with a big name or person having a team and already manufacturers come in.

"We've seen when they come in, the costs hike, even if you try to keep a standard car.

"You are already seeing the tendencies of how things are going to be opened up season by season, which basically means it will get very expensive.

"It'll be interesting to see the rate of development, where maybe we might have taken six or seven years to achieve and they will get there in two years and then let's see what is going to happen."