"I don't think you'll hear much about drivers having to save their tyres this year," Red Bull team boss Christian Horner told the Daily Mail, "but we might hear a lot about having to save fuel.
"My concern is that we will lose an element of wheel-to-wheel racing, of man and machine on the limit.
"Hopefully we won't see a driver having to wave rivals past because he is saving fuel to get to the chequered flag," he added.
Horner said he is worried F1's desire to be more environmentally relevant may adversely affect the sporting spectacle.
"It's a fine line," he said. "First and foremost, it's a sport and should be entertainment. Secondary to that should be the technology for the manufacturers."
Williams driver Bottas, however, did a full race simulation at the Bahrain test last week and said he did not have to try too hard to conserve fuel.
"I didn't have any problem," he told the Finnish newspaper Turun Sanomat.
"I did some practice in the simulator at first and then in Bahrain I was able to do two race distances.
"The most important thing was to lose as little laptime as possible while ensuring you have the fuel you need for the whole race.
"I have to say that, at least for Bahrain, it was not really necessary to save fuel at all. I was able to drive quite normally.
"I think that at most of the races, we will be able to drive like this," Bottas added.