Focused Solar Power

I had a wierd idea the other day.

Could a parabolic dish be used to focus the suns rays in to a single point be used to generate electricity more efficiently that the flat solar cells?

Or could the parabolic dish be used to focus sun rays in to a single point be used to heat water to generate steam to generate electricity and then have a way to capture the steam re-condense it and re-use it. Or at least re-use some of it keeping the overall water usage down.