Generating electricity from renewable sources is half the battle. And then how to store the excess? Where can they be used.
I present the TOP 10 solutions to this problem in the world.
1. Battery power plants
How to store surplus electricity from wind turbines and solar panels on an industrial scale? Connect as many batteries as possible! In Germany, this technology has been available since 2014 (it was developed at the Fraunhofer Institute in Magdeburg).
Europe's largest commercial 10 MW WEMAG battery power plant is already in operation in nearby Schwerin.
2. Big battery on a small island
The largest battery power plants are located in the United States and Asia. And on the Caribbean island of Sint Eustatius (Netherlands Antilles), this technology has significantly reduced fuel supplies for diesel generators.
During the day, the local population, about 4,000 people, has been using battery power since 2016. Energy comes from solar power plants, and in the evening and at night - from batteries installed by a German company.
3. A good pump is the key to success
Pumped storage power plants are the oldest and most proven electricity storage technology. In case of excess water, electric pumps pump water from the lower reservoir to the upper one.
If necessary, water is drained down to provide power to the hydroelectric power plant. However, it is not always possible to find a suitable reservoir and a suitable height difference. In Herdeck, in the Ruhr area, the right conditions have been created for this.
4. Storage locations - Norwegian fjords
Optimal environmental conditions for a pumping and storage power plant in the Norwegian fjord. Therefore, from 2020, the 623 km long, 1,400 MW submarine high-voltage power line NordLink will transport surplus electricity from wind farms in northern Germany, where the terrain is completely flat, on the rocky coast of Norway and is stored there until demand. Fantastic, you say?
5. Electricity is converted to gas
Surplus electricity can be stored as gas. Electrolysis produces hydrogen from ordinary water, which is converted to methane with carbon dioxide. It is pumped into gas storage facilities or used locally to refuel vehicles.
The idea of the gas-to-energy technology was born in 2008. In Germany, where about 30 pilot plants are currently in operation. Shown here is a pilot project in Rapperswil, Switzerland.
6. Liquefied hydrogen
The idea of electricity and gas is developing in different directions. Why, for example, the hydrogen produced by electrolysis has to be converted to methane?
He's a great fuel in and of itself! But how is this flammable gas transported? Researchers at the University of Erlangen-Nuremberg and Hydrogen Energy Technologies have developed a method for transporting it safely in organic liquid tanks.
7. What's the salt?
Salt is found here in these circular tanks installed in a solar power plant in the middle of the Sahara Desert near the Moroccan city of Ouarzazate.
The molten salt stored in them acts as a battery system. It heats up during the day, and at night steam is generated from the accumulated heat, which is fed to turbines that generate electricity.
8. Caverns as underground accumulators
In northwest Germany, there are many caverns - caves in salt layers. Energy company EWE and Jena University researchers turn one of them into a testing ground for storage technology electricity in salt water, which is rich in special polymers that can significantly increase the efficiency of chemical processes. In essence, this is an attempt to build a huge underground battery.
9. The largest "boiler" in Europe
People have long been using thermal energy to generate electricity. Renewable energy instead aims to convert electricity, including surplus electricity, into heat (eg. Power-to-Heat).
Therefore, at the end of 2019, the largest, figuratively speaking, "boiler" in Europe with a capacity of 120 MW for heating 30 thousand households was built by the Vattenfall company.
10. Energy storage on four wheels
When millions of electric vehicles with powerful batteries hit the roads of the world, they will become another important source of renewable energy storage. Smart grids will help: they will stimulate charging at low prices when there is excess energy.