The Keystone XL pipeline would have provided 900,000 barrels of oil per day, roughly equivalent to 1.53 billion kw-hr per day. A typical wind turbine is 2MW nameplate capacity, but at best actually produces about 30% of this on average. This means that in a day it produces 2,000*.3*24 = 14,400 kw-hr of electricity. This means that the Keystone XL pipeline would have transported an amount of energy to the US equal to the output of 106,250 of those big utility-size wind turbines.
Looked at another way, the entire annual output of the US wind energy sector was about 75 terra-watt-hours per year or about 260 million kw-hr per day. This means that the Keystone XL pipeline would have carried energy equal to over 5 times the total output of wind power in the US.
Of course, converting that oil to electricity would involve losses of efficiency as well, no one in the administration (or on T. Boone Pickens’ speed-dial list) having yet figured out a way to suspend the laws of thermodynamics, but hey — the Chinese won’t be complaining.