Thousands of kilometres of new power lines are needed in Germany - a job for energy engineers.
© nolimitpictures - iStockphoto.comIf something is flashing, Stefan Seith has a problem. At the moment several things are flashing: on the digital display of the switching cabinet, four red Xs are lit up. "That means that the measurement isn't working", says Seith. And what about the "W" letters appearing on the display? "They're not good either. Those are warnings", says Seith - but nonetheless he seems unworried. These switching cabinets were only installed here in the Siemens laboratory in Erlangen a few days ago. They look a little like cheap bookcases - but inside them is the very latest technology. Stefan Seith can use them to control energy flow. His most important job: to make the error messages go away. The 29-year-old engineer stands calmly in front of the cabinets and says: "In the beginning we always think: Hardly any of this works. But it just takes a while."
Here, between switches and cables, work is being done on Germany's energy supply. Or to be more precise: on transferring energy. Because in future Germany's living rooms will almost certainly be increasingly supplied with electricity that has come a long way. Generated by Norwegian water power, for example. Or from the Sahara. Or from offshore wind farms that are being built off the German coast. The electricity from these power plants has to be transported from the sea to the shore, and most of it further onward to the south and west of Germany, because that is where energy use is highest. But in some regions there are not enough electricity networks to do this - or they are not powerful enough. "The network issue is a key issue", says Christian Hey of the German Advisory Council on the Environment. "One that has previously been completely underestimated."
It is the boom in renewable energies that is demanding massive changes to network structures worldwide. For a long time they were mainly expected to decentralise supply. Using a solar roof to supply one's own house with energy - that for example was one of the plans suggested by engineers. But meanwhile they have also become the subject of enormous projects, some of them ecologically contentious, such as for example the dams in China. In Germany on the other hand the debate centres on the wind farms in the open sea. Engineers like Seith have to worry about more than just transport routes. Another problem is that the wind is not always strong enough to be able to steadily feed energy into the networks. Unlike conventional power plants, wind farms cannot suddenly produce more when everyone turns on the lights in the evening - or reduce production when people go to bed. The move away from traditional energy sources therefore also requires the development of new storage methods. And engineers are the people to do it.
Stefan Seith for example is working on transporting electricity over hundreds and even thousands of kilometres from A to B. Sometimes he doesn't even know from which source this electricity is coming, and it doesn't matter to him. When he talks about his work he speaks with a Franconian dialect that makes him sound a little like footballer Lothar Matthäus. Seith comes from Reichenbach in Lower Franconia, a village of 800 people, where he plays tuba in the brass band and sometimes takes to the pitch as a defender for FC Teutonia Reichenbach in the county football league. That's his way of balancing out a working life in which he may find himself travelling to China or spending several months in San Francisco. Seith and his colleagues not only review and test control systems for electricity networks beforehand, they are also in charge of installing them in the field.
They were for example involved in building a 1400-kilometre stretch of network in China, where a hydro-electric plant in the southwest of the country generates energy for approximately 5,000,000 homes. This hydro-electric power now mainly lights up the energy-hungry mega-cities of Hong Kong and Guangzhou in the southeast. The networks in Germany will soon also have to be massively expanded. The country's high-voltage power lines currently measure 22,000 km in total. According to figures from the German Energy Agency, over the coming years at least 3,500 further kilometres will be needed at a cost of approximately six billion euros. Because if for example offshore wind farms are to play a major role in energy supply, a transport network will first have to be developed that can distribute these large amounts of electricity from the North Sea across the country. Stefan Seith's next project deals with comparatively short distances: two wind farms located 125 km north-west of the island of Borkum are expected to be operational in 2013 and will then be able to generate as much electricity as a large coal-fired power plant.
In their Erlangen laboratory, Seith and his colleagues are testing the technology with which the energy is to be transported from the wind farm to homes and offices. There are 20 switching cabinets on the left-hand side of the room and 20 on the right; each of them is full of buttons, knobs, processor cards and cables in red, green, grey, black, yellow, orange and purple. In the middle of the room, Seith and a good dozen of his colleagues are peering at almost 40 screens; every few moments he jumps up, bustles about. Sometimes they simulate crisis scenarios here, network breakdowns for example. Then every fraction of a second counts: his computer shows Seith to the millisecond when an outage has occurred in what part of the network. Sometimes it's due to a short circuit, sometimes a damaged switch has interrupted the connection. Seith recognises this sort of thing from just a quick look at one of the many curve charts welling out of the printer. He studies the curves and data like a doctor studies an electrocardiogram. Once the problem has been located, in a real emergency an engineer could immediately be dispatched to repair the fault.
Stefan Seith has been working for Siemens for four years, and for four years electricity networks have been his world. "I like the fact that I'm not just counting bits at a computer, but also get to see the actual installation sites", he says. Even when he's travelling for pleasure he often breaks his journey at motorway rest stops near transformer substations. "My girlfriend already gets annoyed when I want to explain them to her." He was already building switches with a science kit as a child. But that he would one day be helping to supply electricity to Hong Kong or San Francisco seemed unlikely 10 years ago. Back then he had completed a vocationally oriented school-leaving certificate and trained to be an electrician for power engineering. He seemed destined for a career on the production line in manufacturing. But Seith wanted more: he gained his university entrance qualification and studied Energy Engineering and Plant Automation at the Nuremberg University of Applied Sciences. Similar degree courses, such as Energy and Process Engineering at TU Berlin or Regenerative Energy Engineering at the Flensburg University of Applied Sciences, are providing increasingly more specific training for students aiming to work in the energy sector.
When Seith explains his work today, he talks about rectifiers, fibre optics and compensation reactors; but often he just speaks of VSC, TFR, FPT, SVC, DPT, HVDC - engineers apparently live in a mysterious world. HVDC for example stands for high-voltage direct current transmission, a technology that ensures that as little energy as possible is lost on very long transport routes - meaning that it can be efficiently utilised. So far, HVDC has been used mainly in countries such as China and India. But the technology is also considered ideal for network stretches with undersea cables, such as those required for the German offshore wind farms. This is also important for Stefan Seith: he will again be moving to follow his new project - this time out to sea. In order to transmit the energy to shore, a floating platform will be built on the sea, similar to an oil rig. Seith will personally check every switching cabinet on site - and therefore even live on the platform for three months if there is enough room for him. If not, he will probably have to travel to work every day by boat or by helicopter from the shore. Maybe that's the commute of the future.
From DIE ZEIT :: 18.11.2010
3. February 2017
University of Twente
23. January 2017