You want to be careful about your predictions of storage dam life . If you suscribe to the theory that the climate is warming then you will also know that some of these storage dams are receiving less water . E.g The Thompson Dam in Victoria ( non power generating ) .
Both the Snowy system and Tasmanian Hydro experienced significant problems in the drought of the 2000's . Not much good having a hydro system if it doesn't rain or the rain doesn't fall in the catchment area any more .
Speaking of the Hoover Dam , you might find this article interesting :
http://www.slate.com/articles/techn...colorado_river_basin_losing_water_at_shocking
I think it's best that you do some more research into what is actually happening as opposed to what you would like to happen .
Btw . Passing the extra cost on to the consumer is exactly the problem . Consumers simply won't pay for more expensive electricity . One of the reasons that the Abbot government got elected was because the promised to repeal the carbon tax . People like to say they are green but the story changes when they have to put their hand in their pocket .
One more thing . Building dams isn't considered to be the greenest thing that you can do . You might want to think about that .