Why not just rent space at a local power generator (hydro)? The owner/operator would eagerly rent you space and sell you very very cheap electricity...
This is especially true for countries outside of U.S. where everyone is looking for extra income.
The other option is to produce your own electricity and sell back to the grid. Then, your per Kw cost could be 0. The only problem with this option is how much is the capital expense? If we had solar technology that was much more efficient than it is today, this would work nicely.
Its possible but you have to understand that most large hydro is already connected to the grid. So why sell your energy for 1c/kwh when you can sell it to the grid for 5-6c/kwh? The only place that would work is in locations where there is no large market for energy like in some African village or something. Most of those microhydro projects were built by humanitarian groups and given to the tribe. But if you showed up and said, "hey, I'll pay you 1c/kwh for your excess energy." Then they would gladly jump at the offer because at their current situation NO ONE can afford to buy energy.
For the second statement that is ASSUMING you are connected to the grid in the first place. what if you are out in the Alaskan outback and you have a micro hydro project? Do you think you will be connected to the grid? Absolutely not. Those are the types of locations I am talking about. Some river/stream that is in the middle of no where but has the potential to generate 50-100kwh. A normal utility would not develop the resource because they would have to build a super expensive transmission line to bring the power to the market. So no one invests to build the hydro power station. These are the types of locations I am talking about.
The engineering would be pretty simple to do. The bigger problem is getting right of use permits and agreements from landowners. It would be better done in 3rd world countries rather than 1st world countries who are rather anti-growth at the present state.
For myself, right now I have most of money parked in the stock market making 3-5%/year. If I could invest in this project and get a return of 20-30% on my money then it would be well worth the risks.