Ignoring costs, it's "trivial" to do with nuclear energy providing the carbon capturing power. But doing so requires a tremendous amount of power (proportional to how much hydrocarbon-based power we're using now, as noted elsewhere in the comments) and a tremendous amount of resource investment (building the power plants, building the carbon capture mechanisms, etc.). So: doable, but insanely expensive.

That said, if the alternative is the death of most ocean life, the depletion of most of the planet's food resources, and therefore the death of a large chunk of the planet, we may end up reevaluating our willingness to spend that kind of change.