There is a slogan for electric transmission that it is not about how much power you generate. It is about how much you deliver. There is a lot of truth to that. It was the innovations of electric transmission well over 100 years ago that enabled the modern electric system by bringing remote generation to the load.
Today a robust transmission grid is a prerequisite to economically and reliably balance generation and load. With more variable generation resources on the system, wind and solar, transmission is again the enabler. However, regardless how strong the rational for strengthening the transmission grid may be, the opposition against building new transmission can be equally strong or stronger. At few places it is more evident than in Germany.
The German Energiewende set in 2010 the ambitious goals of reducing the greenhouse gases (GHG) by 80-95 % from 1990 levels by 2050 and to have 60 % of the electric power from renewable energy. Not a small task but adding to the transition challenges was the decision following the Fukushima Daichi nuclear accident in 2011 to phase out all nuclear power in Germany by 2022. Nevertheless, probably the biggest challenge will be to develop the electric transmission system to support the changes in power generation.
Already at the start of the Energiewende it was identified that the transmission system needed to be substantially strengthened to move power from the north to south. Most of the renewable power sources are wind power in the north, while most of the load is in the south. The projected delta between supply and demand increased further with the decision to phase out the nuclear plants. Most of the remaining nuclear power plants are in the southern and central parts of Germany. To meet the requirement of more power transfer from north to south the planners saw the need for at least three HVDC (High Voltage Direct Current) lines.
So far, the Energiewende in terms of the transition in power generation has proceeded according to the plans. By 2018 renewable energy had grown to 40 % with wind at 20.4 %. Photovoltaics (PV) stood for 8.4 %, biomass for 8.3 % and hydro 3.2 %. In fact, it exceeds the original goal of 35 % renewable energy by 2020. In stark contrast, when it comes to the three HVDC lines none has been built. Construction has not even started on the first line! The main reason for the lack of progress is the massive opposition against the siting of new transmission lines.
However, there are several signs of breakthroughs for a key project, SuedLink. This project consists of two HVDC lines, one from Wilster in Schleswig-Holstein to Grafenheinfeld in Bavaria, and one from Brunnsbüttel, west of Hamburg, to Grossgartach in Baden-Württemberg, each with a capacity of two gigawatts (GW). TenneT and TransnetBW are the two transmission operators developing the project. The project is truly strategic, since Wilster is also the point of NordLink, the 1.4 GW HVDC link from Norway, which is under construction and expected to be commissioned next year (2020). Connecting with the hydro resources in Norway is intended to help balance the variable wind and solar resources, but the positive impact will be much reduced if the power cannot reach southern Germany. Given its strategic importanceSuedLink is designated a “Project of Common Interest” (PCI) of the European Union (EU), which also supports the project as part of “Connecting Europe”, the fund for pan-European infrastructure investments.
Given the long distance, about 800 kilometers, the original plan for Suedlink was to build overhead transmission lines. After meeting overwhelming opposition, the German federal government with new legislation in December 2015, popularly called the “Erdkabelgesetz”, paved the way for the underground cable option.
Consequently, after BNetzA, the German Federal Network Agency, in April 2016 set the planning guidelines for underground cable corridors, SuedLink changed to make the complete project with underground cable. It will be the longest onshore underground cable project in the world. The cost for Suedlink is estimated to triple from about $4 billion to about $13 billion, and the date of completion has moved out to 2025. The original plan had targeted 2022.
Aware of the permitting and acceptance challenges in the densely populated Germany TenneT and TransnetBW from the start developed an uniquely rigorous and transparent siting process, as well as an extensive public outreach plan. Between March and June 2014 TenneT presented the preliminary project plans at 22 regional info-marts. During this period TenneT received more than 3000 comments and suggestions from members of the public, organizations and local authorities. About 1700 comments were spatially related. In more than 500 recommendations, specific corridor proposals were made. Based on this TenneT checked 122 corridor proposals in detail, of which 98 new corridors were then able to be incorporated into the planning. TenneT presented the results of the previous project dialogue to the public in October and November 2014. In addition, TenneT conducted six feedback info-marts and accepted invitation to more than 30 public debates and information events. SuedLink was one of four pilot projects of the BESTGRID project, funded by the European Commission, and focused on sharing best practices and lessons learnt from implementing grid development projects of common interest in Europe.
With the change to use underground cables instead of overhead lines new proposals for the underground cable corridors were developed in 2016. During 8 weeks in October and November the same year citizens, municipalities, authorities and associations had the opportunity to submit comments on how to adapt to the corridor proposals. In total, TenneT and TransnetBW, received over 7000 comments. The planners of SuedLink then adapted and further optimized the proposals for the corridors. The process has continued with detailed studies of the alternative corridors.
On February 21st this year (2019) TenneT and TransnetBW presented the final proposal, which they filed to BNetzA. It was followed by local information meetings. Approval of the actual route/corridor is expected to be decided before end of this year.
The progress on the SuedLink, both technically and in public outreach, is impressive. It is not a done deal yet. It has taken much longer than originally planned and it will cost substantially more, but all indications are that eventually this project will be completed. In January (2019) TransnetBW received the first partial construction permit for one of the converter stations. This month (October 2019) TenneT and TransnetBW announced that the US company Jacobs Engineering Group has been hired as the central construction service provider. Not only will SuedLink be crucial for the future of the Energiewende, but it will also be a worldwide benchmark for overcoming what long looked like “mission impossible”.