Federer proved too classy for Slovenian Blaz Kavcic in a 6-2, 6-1, 7-6 (7-4) win at Hisense Arena.
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Federer hit 52 winners to his opponent's 14 as he pushed Kavcic onto the back foot.
The faster courts at Melbourne Park meant he wanted to be more aggressive, 17-time grand slam champion said.
"In these conditions and on the hard courts it's what we want to try to do, especially early in the tournament, without taking stupid chances," Federer told a news conference.
"But I did do a really good job for most of the match today. Of course, I was overly aggressive at times, but I'd rather be that than overly passive. But the error counts started mounting as well.
"Overall I started hitting good shots. It was something I was trying to do a little bit today, mix it up, swing the serve around a little bit, also come in.
"I was in command on my serve. That was for me most important, is that there I'm rock solid."
Federer, who was "very pleased: with his performance, backed organizers over the controversial Extreme Heat Policy.
Play was suspended several hours at Melbourne Park, where a top temperature of 110 degrees was recorded.
Federer said conditions were particularly difficult without cloud cover, but was only concerned about whether his match would be played under the Hisense Arena roof.
"I was just concerned about what they were going to do with my match, what the rules were, if they could start it closed and then open it later on or not. I was more focused on that," he said.
"I think today, especially at the beginning, it was very hot. Even though they didn't allow me to warm up outside, because the officials were gone, everybody was resting.
"I had to go indoors. I never actually experienced the heat as such today. Especially if there are no clouds, it's extreme.
"I would assume they did get it right today."
