Having experienced both, neither is more powerful. Love makes you want to change your life- to stay with someone as long as they will want you, to defend them if you have to/need to, to do very much for that person. Hate, on the other hand, can blind you just as much as alcohol or getting more stoned than the Himalayas on crack or something like that and make you honestly believe you're capable of murder/horrible acts.
Hate is more of an in-the-moment strong. Unless you're one of the people that just naturally hates almost literally everything, in which case, either get some help or shut up. Love is more of an "all-the-time" strong. A good analogy may be a river versus a sledgehammer in terms of weathering power. Rivers will abrade almost everything they touch over time, and will do it quite effectively- a river carved the Grand Canyon over millions of years, a river can cut a mountain in two, a river can turn a boulder into pebbles. But it takes a while, but the river is always at it. A sledgehammer, though, you hit something once and you get a good deal of damage but you can't be always sledgehammering away (i.e., you cannot always be in the "hitting something" phase of swinging the hammer- you have to pull it back and swing again). Of course, this is a bad analogy if you work with a sledgehammer regularly because then you're doing this shit quite often anyways.
Hate is more of an in-the-moment strong. Unless you're one of the people that just naturally hates almost literally everything, in which case, either get some help or shut up. Love is more of an "all-the-time" strong. A good analogy may be a river versus a sledgehammer in terms of weathering power. Rivers will abrade almost everything they touch over time, and will do it quite effectively- a river carved the Grand Canyon over millions of years, a river can cut a mountain in two, a river can turn a boulder into pebbles. But it takes a while, but the river is always at it. A sledgehammer, though, you hit something once and you get a good deal of damage but you can't be always sledgehammering away (i.e., you cannot always be in the "hitting something" phase of swinging the hammer- you have to pull it back and swing again). Of course, this is a bad analogy if you work with a sledgehammer regularly because then you're doing this shit quite often anyways.