I'm not sure why people are assuming that an object at warp speed has a lot of kinetic energy.
For one thing, all formulas that we presently have for that in relativity, the ones applicable for objects approaching the speed of light from below, don't apply/give imaginary values for objects traveling faster than the speed of light. It's not like we have any actual evidence-based physics to base such an assertion on.
For another, there's even some sort of argument that the rest mass of a warp-powered craft might artificially appear to be vanishing small, you know like the rest mass of a photon is IRL. A real photon has kinetic energy, but how much depends on its wavelength, not its speed.