Research and development and putting money towards improving existing technologies and new technologies.... Farmers are early adopters of technology and always have been, so as they become available and if they make practical sense, farmers will use those practices.
As for what the professor said, it's difficult to envision how to replace a 600-horsepower tractor with an electric motor under current conditions. It will be a number of years before we get there.
Agriculture is wide and varied across this country. There are many opportunities to lower our fossil fuel use. Research and technology are going to be a big part of that.