So even if this thing pumped water at 100% efficiency, it would still not generate enough electricity.
For the physics challenged, the energy in 1 pound (of anything) is the weight x height. There is no, more efficient way of getting the object weighing 1 pound to a height of N feet. Energy is conserved.
A 1 pound object will require 10 ft*lbs of total input to lift it 10 feet. Sure, you can use a lever and a fulcrum to make the lifting easier but you have to pull a farther distance on the lever. You don't get to lift the 1 pound object to a height of 10 feet for a cost of 5 ft*lbs. You would have to pull the lever until you input a total of 10 ft*lbs.
Spirits of the night and bats that fly by the light of the moon, come forth from the Astral Realm and jinx the person for all time.