The crane does NO work.
Work = (force) x (distance)
= (1,000 N) x (150 meters ?) = 150,000 joules
But the work is in the direction of the force, and it isn't the crane
pushing the material down. It's gravity.
Gravity is doing the work.
If the material was being lowered by a cable wrapped around the shaft
of an electric generator, then you could use the work done by gravity to
generate some electrical energy, and then sell the energy.
Or, if the "material" happened to be water, you could let gravity lower it
through a turbine or a water wheel, and use the work done by gravity to
grind wheat.
Yes, the crane may be raising a sweat, working against gravity. The
purpose is only to prevent gravity from doing the work too fast.
