But you are missing the point "I think"
Since energy can be store ,theroetically it would have no bearing on time travel.
If it is stored it would not have any relevance.
Not disputing energy can be stored, but it is still there none the less, whether it is potential or kinetic. Conservation of Energy's basis for the limitations on time travel looks at ALL energy in the universe. Creation or destruction of energy is absolute, nothing in, nothing out. Energy is finite in our universe and is expressed in two forms, kinetic or potential. Whether it is in motion or stored, it is still a finite amount of "stuff". Time travel would take away or add a small amount at a particular given time in space, which would violate the conservation of energy. This is all theory, not saying it couldn't be done, but if it could, you could throw out conservation of energy as a dependable law and in effect it is plausable that the universe is infinite if energy can be created. There in lies why I believe time travel is impractical, because I believe our universe is finite, and that all existing energy was created, by an infinite God, who exists beyond space and time.