We as human beings like to come up with new, innovative things and we invent something new almost every day. Even if something already exists we do our best to beat the ”good ol’ thing” and make it even better.
This article (in all four parts) is dedicated to hydro-power plants (and it’s turbines) since they are a very big deal. In 2016, about 16,4% of world’s electricity was produced by hydro-power and it presented 85% of produced electricity from all available (so-called) renewable and sustainable resources. This is why, I believe, this topic deserves to be described in depth. In the first part, I will talk about turbines, that are helping to obtain energy from the rivers and in the second part, I will cover the ones submerged in seas and oceans. The third and fourth article will be dedicated to cover the topics related to research before and after the construction and their influence on the environment.
Related article: The truth behind hydropower plants
The turbines in hydropower plants, that are constructed on rivers are usually very hard to see – not because they would be so small but because they occupy a special place in the heart of the construction. There are about 8 different types of turbines being used in such constructions. The place, which a turbine will occupy is very carefully chosen (and approved by many calculations) and the whole construction is often adapted so that the turbine can do it’s best and obtain as much energy as possible. The whole process works on a very simple idea – the blades are attached to a rotor, that moves along the stator and because of this movement, the energy is being generated. You can see a good sketch here.
Why do we like hydropower so much?
Come on, have you seen how much water is freely flowing around most of the world? And we are just letting it do so, not making anything out of it… Seriously!? Of course, we needed to do something to use the situation to our advantage (and not look twice at how everything else takes it)!
The water, that is used for obtaining the power is usually not heavily polluted and since most of the world doesn’t yet feel the problem of not having drinking water, we don’t really give much thought to it. In our eyes, the water has always been there and will always be there and this is also why we refer to it as renewable and sustainable energy. Until the water resources will become really scarce or until we raise our knowledge of all the consequences we are making, our beliefs will stay the same and we will continue to manipulate water resources indefinitely.
The good thing when building a power plant on the river is, that the water is actually very easy to manage. All we need to do is to build a dam, and not allow the water to pass through. The biggest dam ever built is called Three Gorges dam and is located in China. This power plant is capable of producing 22500 mW (22500000 kW) of power, which is equivalent to the amount of energy produced with fifteen nuclear reactors! Moreover, we can produce this crazily high amounts of electricity with very low operating and maintenance costs. Another positive aspect of having a dam built is its capability to protect the areas behind it from floods. The construction is capable of holding back large amounts of water, that can come with heavy rain or by thawing of snow in the mountains.
Types of hydropower plants constructed on rivers
In general, we divide the types of hydro-power plants constructed on rivers into three groups. The impoundment facility, where water is being stored in a reservoir and is then being released to run through the turbine. A pumped storage, where the water is being pumped up to a reservoir in order to save it for the time of need. When this time comes, all we need to do it release the water through the turbine, making it do its job and generate the electricity. The third type is called a diversion or run-off-river. Here, the water runs through tubes, that contain the turbines. After the water passes through, it is simply led back to the river. This power plant doesn’t require a dam but is usually built anyway for other purposes (agriculture, aquaculture, lakes etc.).
However, there are many different varieties of each of the above-listed types of power plants and scientists are coming up with even more every year. The main purpose of these new innovations is, to make them more efficient and lower the impact on the environment.
Do you have any hydropower plants on one of the rivers next to you? Did you notice some changes in the environment after the construction was made? I would love to hear your stories, so please write them down in comments.