RENEWABLE ELECTRICITY #1 HYDROPOWER ENERGY

Generating and using energy in such a way that it doesn’t impact the environment has been pursued for many years, but this green future vision now seems more realistic than ever. While a number of sustainable forms of energy have proven successful and are being scaled up in capacity, other forms of energy are still in their infancy. This is the time to join forces, to apply and combine knowledge and expertise from different sectors. Together we are responsible and together we can make a difference.

Hydropower seems to be a somewhat less discussed topic when it comes to renewable energy. Wrongly so! It seems possible to supply almost half of the world with electricity thanks to hydropower. If we look at the global renewable electricity, hydropower is responsible for 72% of that. Of all the electricity in the world, hydropower supplies 16% of it.1 So we can say that hydropower is very important worldwide for a sustainable future.

What exactly is hydropower?

Hydropower is a form of energy that is generated using flowing water. This happens mainly in hydroelectric power stations, which we often see in mountainous countries. This is logical, because the greater the difference in height that the water bridges, the more hydropower energy you can generate. A dam is often being built in the course of a river, behind which a reservoir is created. Turbines at the bottom of the dam rotate by the force of the water flowing past it. A generator converts this motion into electricity, basically like the principle of a bicycle dynamo.

Why choose hydropower energy

There are many advantages to using hydropower. It is a very clean source of energy. No raw materials are needed to generate electricity, and no waste products are created either. One of the biggest advantages is that hydropower is not dependent on the weather, which makes it a more reliable source of energy than solar power and wind power, for example. You can also generate hydropower when it is needed, which makes the energy source very flexible.

Even though the construction of hydropower plants requires substantial investments, the subsequent costs of generating hydropower is very low. In addition, the lifespan of a hydropower plant is about 75 years.

But there is also criticism...

No one will deny that the construction of dams and reservoirs damages the ecosystem. The habitat of all kinds of plants and animals changes. Nature often has to make way for the construction of large dams, with all the associated consequences. Think of problems concerning fish migration. Fish moving downstream can get lost due to a lack of current above the dam. If they end up in a turbine, it is often fatal. There is a ‘fish ladder’ for fish moving upstream, but not every fish is able to use this ladder. It is therefore not without reason that the International Hydropower Association has drawn up a protocol for the sustainable construction of dams. Although that protocol is rarely used in practice... Fortunately, there are more and more techniques that reduce the disadvantages of hydropower plants and the associated dams and lakes.

Who can use hydropower energy?

As mentioned, most hydroelectric power plants are found in mountainous areas. Among other things, Dutch researchers from TU Delft investigated how much energy can theoretically be extracted from hydropower worldwide. This turns out to be more than fourteen times the amount of energy that was extracted from hydropower in 20173. The researchers also reached the conclusion that there are theoretically as many as 11.8 million suitable locations in the world for hydropower plants. Practice is quite different from theory, which means that by no means all sites can be deployed. Consider technical or economic reasons. The countries that could generate the most hydropower energy per capita are Bhutan, Iceland and Papua New Guinea. It is striking that countries that are now often struggling with energy shortages have great potential for generating hydroelectric power. Think of Bolivia, Zambia, Nepal, Myanmar and Gabon.

There are also countries that are just not suitable for generating hydroelectric power, for example, because they are too flat, too dry or too densely populated. It is possible to export hydropower so that the large amount of energy generated in some countries is not lost. For example, in countries like Norway, more than 90% of the electricity consumed by residents comes from hydroelectric power stations. Part of the energy from hydropower is exported. In comparison, in a flat country like the Netherlands, only a few percent of renewable energy comes from hydroelectric plants. In countries like this, for example, solar, wind and hydrogen energy are much more widely considered.

Sources

1. publicatie van planbureau voor de Leefomgeving (PBL) en de Universiteit Utrecht in Nature Energy

2. Kennisbank essent.nl

3. Artikel ‘Waterkracht in theorie goed voor 1/3 energievraag, De Ingenieur