Uranium contains 8.3 *10¹² Joules per gram according to Wikipedia. According to physics.org, there are 4.6 *10¹⁸ grams available dissolved in seawater. 3.82 *10³² Joules available just in Uranium dissolved in seawater. The first question is how to recover that resource.
So I’ve got 1% of your required power available in the near future.
Another question becomes how much is available, and how to collect uranium from lower grade deposits.
Uranium is constantly being be dissolved from magma at seafloor spreading (there’s a lot of hydro thermal activity in the new rock). how fast does this recharge sea water uranium is another question.
How to apply the force: We could apply force with strategic explosions to slowly hammer earth into a larger orbit. we could hammer the moon and let it pull the earth, or something else . . .