EDIT:(and what heuhen said made abselutely no sense to me..... huh?)
That's because you didn't have that type of education like I had once at the Engineering school, Where we had to study this type of heating system that we have up here in Norway, it work this way:
Take out "heat" out of sea-water by using that to heat up an different type of water that are at a different density than normal water thus it will start to steam at temperature already down to 4-9 grade Celsius, have that water to go into the turbines.
Since this water goes to steam at far lower temperature you can get more power out of the water, even at an cold winter-day!!
It's called for heat exchange. The same principles can be found in an air conditioning system. only made in a different way, and without water.
Note: some water-types or if you want to call it an condensed fluid, are transferring to steam when they are getting cooled down. But he want an different system.
This system is similar to that one we are using in a city here in Norway to heat it up by using seawater:¨
They look like this, and in AAlesund they are using three of them, just at a bigger scale, heating up houses during winter for around 40000 people:
This system can probably be also used in an solar system, the difference is that instead of seawater, you use the water from Solar panels to heat up the systems.
There are many ways to do it, many systems out there, I have just had about this systems at school since we was talking about trying to design a larger system that used an seawater-exchange to heat up the power-plant of a ship.