what are the benefits and down falls of water expanding when it freezes?

Question

What are some reasons it is good that water expands when it freezes and what are some reasons it's not so good?

Answer 1

Benefits:
1) the expansion of water as it freezes makes it less dense than the water, it floats, and provides an insulating layer that allows fish to survive underneath.
2) you can get a beer (water) really cold. The pressure (and perhaps CO2 interference) keeps the beer (water) from freezing.
Not so good:
1) Water gets into cracks (sidewalks, monuments) and freezes. As it expands it makes the cracks larger. In the sun, the ice melts and then refreezes causing the cracks to enlarge.
2) If you get your beer(water) too cold, the bottle breaks.

Answer 2

If it did not, life could not exist. Ice would sink to the bottom and never get a chance to thaw, Much of the northern soils are made because Ice splits rocks.

It is also why plants and animals are killed by freezing, when a piece of ice forms in the cell and breaks it open.

Because of the way it freezes it stores huge amounts of energy, making the Earth livable, without that energy storage water could not exist out in the open much.

Answer 3

I'm not sure. But I live in Alaska and always wondered if, on a very large volume, that the expansion of water freezing could be turned into an energy source. That would be a free and renewable source.Is that possible? Any engineers care to field this one?