There’s a battery in Switzerland that runs on water!
You come across different types of batteries in your everyday life! These batteries vary in shapes and sizes and power our day-to-day appliances. But have you ever come across a battery that runs on water? Yes, there exists a battery like that! On July 1, 2022, Switzerland revealed its gigantic water battery in the Swiss Alps. Located in the Alpine region of Switzerland, the water battery can store enough electricity to power 400,000 electric vehicle batteries! It took 14 years to construct the water battery, known as Nant de Drance. It is a significant development in the effort to store renewable energy. So, what exactly is renewable energy and how does this water battery work? And how can this massive water battery stabilise electricity in Europe? Come, let’s find out.
Basics of renewable energy
Renewable energy is produced from natural resources including wind, water and sunlight. It is also dubbed as ‘clean energy’ or ‘green power’ since it doesn't contaminate the air or water. But why do we need to store them? Well, by storing renewable energy, we can lower our emissions of greenhouse gases such as carbon dioxide and reduce our dependence on polluting fossil fuels that negatively impact our health and environment.
What exactly is a water battery?
A water battery, also known as a pumped storage power plant, is a form of hydro-electric energy storage system. The battery is made up of two huge pools of water at different heights. By moving water from the lower pool to the higher pool, it may store extra power by ‘charging’ the battery!
What makes Nant de Drance so special? Traditional storage hydropower plants on river systems require the building of dams, disrupt animals and harm the ecosystems. Nant de Drance, on the other hand, has utilised the existing dam and reservoir facilities, with most of the construction being completed underground, thereby minimizing its impact on the environment.
Nant de Drance at a glance
The 600-metre-deep water battery, Nant de Drance, situated between two reservoirs in the Swiss canton of Valais is being hailed as a significant milestone in Europe's shift to green energy. Let us see what this is all about!
The project consists of 17 kilometres of underground tunnels that house six enormous turbines. The turbines are driven by water that falls from the higher reservoir into the lower reservoir that is the length of two football fields to generate energy. As previously mentioned, two pools of water at various depths are required for a water battery to store power. So, one of the two reservoirs in this project, the higher reservoir (Vieux-Emosson), was elevated 21.5 metres to increase its capacity. It can presently accommodate 6,500 Olympic-sized swimming pools' worth of water. Yes, 25 million cubic metres of water!
But why was there a need for storing renewable energy? Well, wind and solar energy don't provide a reliable source of electricity. So, pumped storage hydropower plants are crucial for renewable energy. These turbines with variable speeds swiftly supply power into the system, lowering the possibility of blackouts.
How does Nant de Drance store energy?
This water battery pumps water from the lower reservoir into upper reservoir when there is excess of power in the system, such as when solar or wind energy is generated. It uses electricity in the process. When electricity demand exceeds supply, Nant de Drance pumps water from the upper reservoir and returns it to the lower reservoir generating energy! So, the top reservoir acts as a sizable ecological battery that stores energy until it is required, keeping the generation and consumption of power on the system in balance.
Are you wondering how much energy can it store? With a storage capacity of 20,000-megawatt hours and a rated power of 900 megawatts, Nant de Drance can help Switzerland make the transition to a future driven by renewable energy sources. Nevertheless, to do this, Europe will need to construct 200 gigawatts of energy storage capacity by 2030 – more than four times its existing capacity!