topography required for transforming a valley to a Reservoir + any other Information you are willing to share?

Hey Viable, the straight answer is any river in a valley. Deeper is better. This was the mantra back in the 30's and 40's when we built Columbia River Gorge, Hoover, and similar facilities. You don't really need to post a question here for that answer, even Wiki has a good write up on it, link is below.

In trying to understand your question better, I looked back at some of your earlier answers, but it appears most of them are political. In my experience, most people posting questions about renewable energy under politics don't want an answer, just a fight. But I still don't understand what you're trying to accomplish by reading your bio. Changing the economics of renewable energy to make it compete is like changing the temperature of an oven to make it safe. By making it cooler, it's safer, but the turkey won't cook. Renewable Energy, like oil, nuclear and natural gas, is subject to the same economic forces as everything else. I'm guessing what you want to do is make it cheaper, or convince people it's more worthwhile. If that's the case, the best way to accomplish either of those is to advocate it, with your opinions, votes, and your wallet.

We started 12 years ago, and today our home is completely powered by the wind and sun, heated primarily with wood and solar, and collects rainwater for part of its domestic supply. The grid is still connected to our home, but we make very little use of it, so our bills run about $8 a month, mostly fees and taxes. When the power goes out in our town, we still have lights, difficult to put a price tag on that.

We also now teach renewable energy seminars at the local schools, discussing things like coal ash pollution, loss of habitat in mining operations, and annual death rates in coal extraction. These things are not generally included in your electric bill, but you end up paying for them with large clean up funds, they come from your taxes instead. We discuss the physics of solar panels too, but that information is easier to find. The turbulence I run into doing this is from people who have not studied the science stating things like, "a solar panel will never generate as much energy as was used in manufacturing it." Actually they do, but that is just the diversion. A coal, oil, natural gas or nuclear plant doesn't either, because once you build one, you then have to feed it fuel, which it converts to electricity at a rate less than 100%, so it keeps digging itself a deeper hole that it can't crawl out of. At least a panel, or wind turbine can get even one day. Even the renewable advocates miss this point, they have already lost their way in the argument.

Renewable Energy is already economical if we add up all the costs of the traditional sources of energy, but we don't. Even the CEO of BP Petroleum last year stated that the cost for electricity from nuclear sources is much more than the cost from wind. The power companies have figured that out too, that's why all the turbines are being built. Many people, even liberals, complain that turbines don't work, yet they have never laid a hand on one. I have one in my yard running my house right now, they don't want to hear about it. If you don't believe the cost analysis above, just ask anyone in the Chicago area about rates, the highest density of nuclear electricity in the 48 states, their rates are astronomical compared to the pacific northwest, which is mostly hydro.

Getting back to your original question though, a renewable source of energy that is reliable 24/7, have you heard of the desertec initiative, making solar based grid electricity from the suns heat in the Sahara Desert? A link is below. Basically, using tanks of oil holding thousands of gallons that are recirculated through trough solar collectors the oil is heated to 600 degrees, which is then used to boil water to run a turbine. What is the point? The oil stays hot enough all night, well above 212 degrees, to make solar electricity at night when the sun is not shining. A thermal battery if you will. When it is complete, it will run all of Europe on the sun and heat in the northwest corner of the African Desert. It's cheap, it always works, and you don't need to dam up a river valley to get to it. It will work in our Southwest US as well, with no habitat destruction, no mining operations, or wars in the Middle East to supply it. Will that fill your perscription? Good luck Viable, and take care, Rudydoo