Basic Hydro Power - part 1

Well I guess many has already understand better that I do about hydro power, however there are still people who simplify the complexity of hydro power even the micro one. Questions like: if I have 500 liters per second, how much kW would I get, still comes to experts. This kind a thing needs an education and complex explanation of things would not help at all. So, I will try to give very basic understanding of how modern hydro power (micro size maybe to be specific) works. Please correct me if I am wrong.

Hydro power is basically power generation by utilizing water power (in this case in general the potential energy of falling water). Therefore the original use of hydro power is to give movement. Water drops move a water wheel that eventually makes certain mechanism to rotate or move and provide specific service. In the old days many mills are using hydro power directly to give movement to their mill facilities. Old hydro power systems use the weight of the water to move the wheel. So the first important point is weight of the water or mass of the water. The second important point is the gravity acceleration. Force is created if there is an acceleration to a mass. Since water always runs to lower level then gravity acceleration works on water mass. Even when flowing slowly the water already produce force (That's why flood flow is very destructive because not just gravity acceleration that works on the flowing water and makes it flowing very fast). And to produce power, water has to drop or fall from certain height. The higher the height the more the power. So we can already see that usually in hydro power, the higher the water falls, the more power it may produce (potential energy).

There is another important aspect, the weight of the water. Weight of water depends on specific mass characteristic of the water (i.e. kg/m3 unit) and volume of the water. As you already know force depends on the mass (or let's say weight). The heavier the water the more force it produces. Heavier water means more volume of water (let's say in certain time unit e.g. second). So 100 liters of water dropped from 1 meter height will produce less force compared to 200 liters of water dropped from the same height (provided that the specific mass or specific gravity of water is the same and gravity acceleration is the same). Therefore the more volume of water flowing per unit of time the better it is.

So, if someone talks about hydro power potential he or she should clearly mention how much is the flow (meter cubic per second or liters per second) and how high the water will drop (meters). The volume per second is called flow, the height of the drop is called head. So find you head and then your flow. That's for the beginning. Head and flow is the key for hydro power