The main idea that you can get the clear energy from the usual sources.

The system allows to generate electricity with the use of the liquid working body, capsule generators,
and the natural difference in the pressure ( ocean - mountains or ground - mountains )

As the pressure on the ground is usually 1.25 kg/m3
we can get additional 100 g/m3 of free pressure on every 1 000 m height as there is natural height difference

System consists of the two main components: tubes and hydraulics turbines on the junction of pipes

If could we use the pipe of cones like tubes we can get the much more pressure for the better system
If could we use the two pipes we can get the additional source of energy for the high mountains

This allow us to get the clean energy 24 hours * 365 days per year
The system does not depend on the weather or climate, easy to maintain and it is just depend on working body type ( liquid salt, thick oil or water )
The best for the ecology if do you place the pipes under the ground like the Roman aqueducts

Links :
http://kiev.all.biz/en/hydraulic-generators-g1398020 - for the small power systems 3 000 USD
http://www.power-m.ru/eng/products/Default.aspx?section_id=175&element_id=1815 - for the big system