Hydrogen a great all-rounder
Amprion und die chemische Industrie werden innovativ, um Deutschland klimaneutral zu machen
Amprion is paving the way for a climate-neutral energy system. The task of controlling this system demands innovative and powerful technologies. Amprion has made its System Operation and Control Centre in Brauweiler near Cologne fit for the future by completely rebuilding it. Men and women work there in shifts to keep the power grid functioning stably and reliably – and not only in Amprion's control area, but also in Germany and Europe. The expansion of renewables poses enormous challenges. The new System Operation and Control Centre helps to master them – as an important milestone on Amprion’s way to becoming a next-generation transmission system operator.
In the System Operation and Control Centre, our engineers monitor the current flows, voltage and frequency levels of the transmission grid. The most important tool that helps them to carry out this task is a video wall that measures an amazing 108 square metres – one of the largest in the world in the energy sector. “It rightly reflects the degree of system responsibility Amprion holds for the stability of the German and European power grids,” notes Dr Christoph Schneiders, boss of the Brauweiler control centre.
Among other things, his team also keeps an eye on the transmission grids between northern France and the Czech Republic, as well as between Denmark and northern Italy – and therefore covers the largest monitoring area supported by online information in Europe. “Europe’s national power grids have long been interconnected,” he says. “If there is a problem in a neighbouring country, this can affect us, too. That’s why we monitor such a large area and are also able to offer assistance if needed.”
At the click of a mouse, lines of continental Europe's interconnected grid can be displayed on the video wall. Power lines, transformer substations and switchgear are depicted in different colours. Two state-of-the-art data centres process millions of pieces of information from the grid every day. For example, the state of more than 50,000 switchgears in 800 substations and the measured values of around 2,800 lines are recorded every three seconds. These are visualised in the System Operation and Control Centre and combined to form a continuously updated overview of the situation.
Graphics, tables and digital indicators (“needles”) complete the image of the power grid. Among other things, they display the voltage, current flows and frequency in Amprion's grid. The expansion of renewable energies and the growth in electricity trading across borders pose increasing challenges to the experts in Brauweiler. The more electricity is generated from wind and the sun (depending on the prevailing weather), the more complex the processes in the transmission grid become.
At the same time, electrical energy in Europe's internal electricity market is being transported over ever greater distances to consumers. The voltage, frequency and current must be monitored constantly in order to assess grid and system reliability. In order to regulate the voltage, the control engineers feed in or compensate reactive power as required. To stabilise the frequency, they can deploy balancing energy; that is, instruct power plants to feed more or less electricity into the grid, for example. Current flows can be controlled by switching measures or interventions in power plant schedules – what’s called “redispatch”.
the video wall in the Brauweiler System Operation and Control Centre is the largest in Europe. At the click of a mouse, not only power lines belonging to Amprion, but also those of neighbouring grid operators in continental Europe's interconnected grid are displayed.
Dr Christoph Schneiders heads up Amprion's System Operation and Control Centre in Brauweiler. “It's the nerve centre of our grid management system,” says the 41-year-old electrical engineer. He is one of the people who helped develop the new System Operation and Control Centre. He has a doctorate in the field of visualisation for control systems. How complex situations in transmission networks can be visualised in a comprehensible way was the subject of his doctoral thesis. There's one thing he's absolutely certain about: “The climate goals that Germany and Europe have set themselves can only be achieved if we integrate renewable energies into the power system and also introduce them in other sectors. The new System Operation and Control Centre will play a key role in this development.”
The wind power generated in the North Sea passes through the Amprion grid on its way south and affects line utilisation and voltages in the grid area. A display developed specifically for this purpose shows how much electricity the wind farms in the North Sea are delivering at a particular moment. By integrating this display, the operation and control centre is preparing for the moment Amprion connects the offshore wind farms to the transmission grid. The different-coloured tiers show how much offshore power is being fed into the grid at which connection point. If the picture unexpectedly changes significantly, the control engineers are warned in advance and can prevent overloads in the grid.
The generation of electricity from renewables fluctuates greatly depending on the weather. For this reason, Amprion utilises various forms of artificial intelligence in the operation and control centre to predict the amount of electricity that will be fed into the grid. Self-learning algorithms evaluate weather forecasts from various sources. Those algorithms that have to date provided the best forecasts in comparable general weather situations are given greater credence and a bigger say in the calculations for the next forecast.
The energy system is changing not just because of the expansion of renewables. Cross-border exchanges of electricity also continue to increase. This requires highcapacity “power bridges” that connect the national grids. One of them is ALEGrO – the first direct power link between Germany and Belgium. This 90-kilometre-long power line comprises an underground cable between Aachen and Liège and went into service in 2020. ALEGrO is shown in purple on the video wall because it is a DC link. The current flows are easier to control than in the case of AC links. But at the same time, it's a real challenge to coordinate operation of the new DC link in the close-meshed AC transmission grid. Amprion will be able to profit from its experiences with ALEGrO when, for example, the 340-kilometre Ultranet DC link between North Rhine-Westphalia and Baden-Württemberg goes into service.
The men and women of the System Operation and Control Centre must monitor the condition of the transmission grid constantly. This is why Amprion uses the very latest visualisation software to provide them with an overview of the situation at a glance. One example of this is this map: it illustrates the current flows in Amprion's grid and combines them with a picture of the regional power balances. This makes it possible to see whether more or less electricity is being generated than consumed in the respective region. In the north (depicted on the left-hand side of the map), wind farms feed in so much electricity that there is a surplus – shown in red. The situation is different in the south (right), where industrial centres consume a lot of electricity: the “current sink” in this region is displayed in green.
Because Amprion's grid is located right at the heart of Europe, it has become the hub of European electricity trading between north and south, east and west. Amprion has taken on far-reaching coordination responsibilities in Europe's EHV grid, without which the European internal electricity market wouldn't function. This is why the video wall in the Brauweiler System Operation and Control Centre also includes a map of Europe that displays system statuses, alarm messages as well as cross-border electricity flows. Countries coloured blue are currently importing electricity, while countries coloured red are exporting electricity. Imbalances can also be easily identified and countermeasures initiated more quickly. To this end, Amprion works closely with the other transmission system operators in Europe and, as “synchronous area monitor” (together with Swissgrid), has a key role in keeping the system frequency stable in the Continental Synchronous Area.
Power generation and consumption must be in equilibrium at all times throughout continental Europe's interconnected grid, aka the Continental Europe Synchronous Area. If it isn't, the frequency will deviate from the specified value of 50 hertz and the system may become unstable. A kind of tachometer on the video wall in Brauweiler displays the frequency deviation at any given moment. If the frequency fluctuates by even a few millihertz, the digital needle deflects. Usually, it's always moving just a bit. But if a deviation in one direction persists over a longer period of time or if the deflections become too great, the control engineers have to take action. They do so by using balancing energy and other instruments. In order to ensure system reliability and availability, they may, in exceptional cases, take comprehensive measures. Here, too, they are supported by state-of-the-art protection and control equipment. Extreme situations and system disturbance scenarios are regularly trained for in the simulator.
Amprion und die chemische Industrie werden innovativ, um Deutschland klimaneutral zu machen