The three phases of the energy transition

Energy world in transformation

The energy transition is one of the great innovative projects of our times. Together with its many partners Amprion is driving the process forward. The goal is to make the energy of the future safe, sustainable and economically efficient. But the challenges are great. Next we take a look at the energy world, past and future.

Das Piktogramm zeit die Worte/Ziffern 'Phase 01" in rosa Schrift.

Energy transition 1990–2013:

Dynamic expansion of renewable energy. Start of the restructuring of conventional energy production. Planning of grid expansion.

The road to the energy transition was paved with protest: since the 1970s an ever-growing environmental movement has stridently demanded change: away from coal, crude oil and nuclear energy and towards renewable energy. With visible results. In 1987 the first German wind farm was connected to the grid in Schleswig-Holstein. Shortly afterwards the political world took its first steps towards the new energy world. The Electricity Feed-in Act (Stromeinspeisegesetz) of 1990 required suppliers to give preference to green electricity produced by small-scale providers at prescribed feed-in tariffs.

This created the foundations for the rapid expansion of green power generation: by 1999 the installed capacity produced by wind turbine generators had increased more than 70-fold to 4.3 gigawatts. Further legal underpinning came in 2000 in the form of the Renewable Energy Sources Act, which prescribed the progressive replacement of fossil energy sources by renewables. Attractive feed-in tariffs and growing environmental awareness fuelled the boom. By 2010 the share of energy produced by wind, sun, water and biomass had risen to 24 per cent. “It was back then that the first studies for the energy system of the future came out”, says Gerald Kaendler, head of Asset Management at Amprion. “However, nobody imagined that the actual expansion of renewable energy would exceed all the forecasts.” The following year a further structural change was initiated: after the Fukushima disaster the federal government decided to decree the shut­down of nuclear reactors, with the oldest generators being removed from the grid immediately. The remaining nuclear power stations will go off line by the end of 2022. “We immediately realised”, recalls Kaendler, “that it would be impossible to develop the new generation landscape without a stronger and more flexible grid, so we got down to work without delay.”

Germany became an energy transition country. Then in 2014 the climate protection goals approved by the European Union lent further backing for the German approach: in order to limit global warming to two degrees Celsius, by 2050 greenhouse gas emissions were to be reduced by at least 80 per cent as compared with 1990. Thus the transformation of the energy system to low-emission, sustainable generation became a pan-European project.

But how did the German energy system respond to the transition? Increasingly power was no longer being produced where it was consumed but where the wind was blowing or the sun shining. “Generation remote from the load”, the experts call it. However, this is not what the power grid was designed for. Accordingly it would have to undergo wide-ranging renovation and expansion in order, for instance, to convey wind power from the north to the centres of consumption in the west and south. In 2009 and 2013 the legislators therefore gave the green light for major grid expansion projects, to be implemen­t­ed by the transmission system operators over an aver­age timespan for planning, approval and construction of up to ten years, and even longer for the largest projects. On top of this, although there was widespread public approval of the energy transition, the associated measures by no means always met with acceptance. “We have learnt that grid expansion can only succeed through intensive dialogue with local people”, says Kaendler, “But for that we need time.” As a result, renewable energy grew faster than the infrastructure for its transport. And that in turn led to ever more frequent stresses and bottlenecks in the grid.

The pictogram shows the proportional shares of renewable energy.
Das Bild zeigt eine Trennlinie | The picture shows a dividing line
Das Piktogramm zeit die Worte/Ziffern 'Phase 02" in lila Schrift.

Energy transition 2013–2025:

Grids under stress. Expansion progress. Planning cross-sectoral electricity usage. Nuclear shutdown the guiding principle.

»These days there are a number of hours each year when we are running our grid at its technical limits.«

Joachim Vanzetta,

Amprion system operation and control manager

Too much stress is unhealthy. What holds true for people also applies to a power grid. This stress is generated by ever greater, sharply fluctuating, weather-dependent volumes of electricity which need to be transported elsewhere. Some days wind and solar power inundate the regional networks, and the transmission networks have to convey the electricity to the regions with the heaviest consumption. Other days the renewables produce hardly any electricity, and then gas- and coal-fired power stations must spring into action. However, more and more plants are leaving the grid because many of them cannot operate economically in competition with subsidised wind and solar power. As a result the reliably available capacity which is so vital for security of supply is diminishing. The transmission networks are under pressure. They are transporting electricity from other parts of the country as well as from other European countries.

As a result, particularly in the winter months many lines are operating close to capacity, and can offer minimal reserve capacity should others break down. A stable grid, though, is the cornerstone of a secure energy supply. “Power lines are the lifelines of the German economy, and as a transmission system operator we are responsible for them”, says Dr Hans-Jürgen Brick, Commercial Director of Amprion.

How stress management operates on the grid may be observed in Brauweiler near Cologne, where the legislators have given Amprion System Operation and Control Centre the tools needed to respond to bottlenecks in the grid. One of these is known as redispatch: Amprion’s control engineers can perform unscheduled power station ramp downs or generation increases as and when system security demands. However, even these options are eventually exhausted, and they cost a great deal of money: power station operators are compensated if their facilities are ramped down unexpectedly, as well as being paid if required to mobilise their reserves at short notice. As a result, in 2017 transmission system operators made more than a billion euros in payments in order to prevent bottlenecks. More than 100 million euros of this was attributable to the Amprion grid. These costs are met by electricity consumers.

The picture shows a map of Germany with the installed capacity figures processed in the text.

And the number of critical situations is mounting. “These days there are a number of hours each year when we are running our grid at its technical limits, and this is a growing trend”, notes Joachim Vanzetta, Amprion’s System Operation and Control Manager. Accordingly it is all the more important for grid expansion to gather pace. Amprion will further increase the efficiency of its grid to ensure that it can cater for and transport significantly larger quantities of electricity fed in from renewable energy sources. Alongside the reinforcement of important existing alternating current (AC) power lines and the installation of new ones, this process will also involve the completion of vital direct current (DC) projects: A-North connects Emden with the Rhineland; Ultranet is running from there to Phillipsburg. The same applies to the expansion of the cross-border interconnectors which will further strengthen the links between the Amprion grid and the grids in neighbouring countries. One of these interconnectors is ALEGrO. In 2020 the first German-Belgian power line will commence operation. This also represents an innovative solution in another respect, as it features a DC underground cable whereby the flows of current to and from Belgium can be precisely controlled. The technology for this is known as an extra-high-voltage direct current trans­mission cable. It will help make the grids in Belgium, the Netherlands, Luxembourg and Germany even safer.

Fluctuations on the grid are large because ever more smaller “power stations” are producing sun-and-wind-dependent electricity. “We need to know exactly how the weather, electricity feed-in and consumption patterns are likely to change over time”, says Vanzetta. “Only then can we maintain the stability of the power system. That is why efforts began some time ago to make our grid ever more intelligent.” In 2019 Amprion will reach a further milestone in the digitalisation field, when the new central control station in Brauweiler comes on line. Aided by cutting-edge technology, the grid control system will process vast volumes of data on the oper­ation and capacity utilisation of overhead power lines, underground cables and substations, as well as data such as weather forecasts and power station schedules. The new control system will collate and evaluate all of this information virtually in real time, and notify control engineers of places where bottlenecks might occur, both on the Amprion grid itself and far beyond.

Vanzetta and his colleagues also have the adjacent domestic and international transmission networks in their sights: the entire “observability area,” in fact. This is because congestions there could also have an impact on the Amprion grid. In parallel the company is also working to set up new data flows between energy producers, consumers and distribution system operators. These will become indispensable to maintain equilibrium on the power system of the future.

However, all that will not be enough in the long term: when there is a lot of wind and sun, more renewable energy is frequently produced than can be transported at that moment, and to date there is no prospect of electrical storage facilities large enough to accommodate these surpluses. Because of this, “the energy transition is more than just a power transition”, notes Professor Manfred Fischedick, Vice President of the Wuppertal Institute. He regards Germany as standing on the threshold of incipient systemic restructuring which will embrace not just the power sector but also sectors such as transport, residential accommodation and industry, and argues that the surplus electricity from renewable energy sources will be used there, in order to radically reduce carbon dioxide emissions. Kaendler shares his vision: “Alongside grid expansion, the intelligent coup­ling of sectors such as electricity, gas, heat and mobility will be a further step towards designing a future-proof energy system. Together with our partners we have already begun working on this.”

Infographics on extreme network situations. The infographics shows two numbers in comparison, visualized by circles of different sizes. One circle contains the percentage 96, the other circle 0.5. 
Below the circle with the 96 is written: of Germany's entire electricity consumption was covered by renewable energy sources at 2. a.m. on 7 June 2017.
Below the circle with the 0.5 is written: The proportion of consumption covered by renewable energy sources at 5 p.m. on 8 January 2017. The remaining 99.5 % was supplied by conventional power stations.
Das Bild zeigt eine Trennlinie | The picture shows a dividing line
Das Piktogramm zeit die Worte/Ziffern 'Phase 03" in blauer Schrift.

Energy transition 2025–2050:

Expansion of cross-sectoral use of energy and electromobility. Onward march of digitalisation. Achievement of EU climate goals.

The energy world of the future will be based chiefly on electricity generated from renewable energy sources. The vision is one of companies that not only use energy to operate installations but also convert it into hydrogen, synthetic gas, fuels and chemicals. That way it can either be used for industrial production or stored. Private individuals will charge their cars with energy from renewable sources. “The entire economy will use green electricity”, forecasts Kaendler. “Because every kilowatt-hour of electricity from renewable energy sources helps protect the climate.”

However, every new “power station” using renewable sources, every installation converting electricity into synthetic gas, every new electric car, further increases the challenges facing the power grid. “The processes will get ever more complex”, predicts Vanzetta. “Power generation and consumption by millions of actors will have to be coordinated”. He expects the pace of digitalisation to increase, and to do so across national borders. New information and communication technologies would then help to further improve the coordination of flows of electricity within the European internal market, thereby strengthening cross-border collaboration. On top of this come new questions to which Kaendler, Vanzetta and their colleagues are devising answers: how will we continue to guarantee data security? How can the grid be kept stable as the proportion of fluctuating renewable energy grows to 60 per cent and beyond? How can grids based on renewable energy be brought back on line after widespread breakdowns?

As yet grids and system operation and control processes are not ready to meet all these future challenges. However, research is already under way at Amprion and its partners. Thinking ahead and seeking economically sensible solutions: that is how Amprion views this task. Unlike in 1990, it is founded on a broad societal consensus – and there is a plan for the future. “Thanks to the EU climate protection goals our direction of travel has been mapped out until 2050”, Gerald Kaendler points out. Nevertheless, this much is clear: to make the third phase of the energy transition a success, we will have to put in place cross-sectoral, macroeconomic solutions. As Kaendler puts it, “restructuring our energy system is and will remain a community task, and at Amprion we will be providing important impetus.”

The pictogram shows the proportional shares of renewable energy in gigawatts.

Text: Volker Göttsche | Illustration: Marie Luise Emmermann