Multiple electrical transmission towers against a blue sky.

Grid Expansion in Germany and Europe

In Germany and in Europe, the expansion of our power supply sytem increasingly gains significance. Nadja Pappenberger offers exciting insights into this field.

by Nadja Pappenberger

Interview with Nadja Pappenberger

CDM Smith

How is the power produced and where is it originating from?

Nadja Pappenberger

Electrical power is generated in multiple ways, still from nuclear power as well as by combustion of fossil fuels, e.g. coal. Renewable energy on the other hand is being generated by e.g. hydroelectric power plants, wind energy converters or photovoltaics without climate-damaging emissions, at least during energy production. The efficiency of these facilities varies depending on the facility’s location, so they are to a greater or lesser extent profitable. Other than those finite resources of fossil energy production, the sources of renewable energy are infinite or at least renew relatively quickly.

CDM Smith

What’s the status quo in Germany?

Nadja Pappenberger

Triggered by the nuclear accident in Fukushima/Japan, Germany pioneered in starting the energy transition. Nuclear power has been imposed with an expiry date, and power supply by fossil fuels is not compatible with the existing climate protection objectives. Hence, new ways of energy production must be established on a large scale, and the share of renewable energy increases consistently. Therefore, further expansion of wind energy converters is a key focus, particularly in the Northern and in the Baltic Sea along with a shift from decentralized energy production towards a central energy supply, e.g. offshore wind converter parks in the Northern Sea.

CDM Smith

How is grid expansion developing in Europe?

Nadja Pappenberger

Actually, grid expansion is a pan-European issue as power supply lines do not stop at a country‘s frontiers. Particularly, the insufficiently developed German power grid has caused major problems and near blackouts in neighbouring Poland, but also in more distant countries like Spain. The European grid is interconnected to collect but also release peaks in production as well as in consumption. But: Power that has been released into the power lines will move up to that point where it is being utilized. And: Power follows the physical principle of flowing the way with the least resistance and therefore might take the way through a less utilized power line, ending up making its way through e.g. Poland. The problem with this prolonged current flow is that it is not planned for, and this on the other hand might overload the supply line and in worst case cause a blackout. These unplanned current flows are so-called ring closures and unfortunately are not that rare. So, the insufficiently developed German grid in combination with Germany’s location right in the centre of Europe represents a serious problem from a European point of view.

CDM Smith

What is the "NOVA principle"?

Nadja Pappenberger

It is a concept of profitability. Simplified it means grid optimization before grid enhancement before grid expansion. Simple measures exist to increase the electrical current flow, e.g. by deliberate monitoring of the power lines. And cooled power lines are able to transport more power than uncooled ones. Therefore, power lines above ground on windy cooler days will transport more power than on hot windless days. Then there are existing 200kV lines that could be enhanced to 380kV by means of reinforcing measures. Also, in this case the existing lines would remain utilized. Finally comes the expansion, meaning finding new routes which is not all that easy in Germany.

CDM Smith

What impact does the grid expansion have on humans and the environment?

Nadja Pappenberger

Regarding the impact on humans, the question should be the other way around as it’s us humans who demand for the grid to be expanded. We shouldn‘t forget that aspect. Nobody is willing to go without electrical power, e.g. hospitals, waterworks, water treatment plants and municipal waste combustors need to be kept running. Our modern life is unthinkable without electrical power. At the same time, no-one wants to have a utility pole standing in their backyard or to live next door to a transformer station. In Germany, regulations exist on how close to a residential area the power supply line may be built. Ironically, there are no existing regulations on how close to a power supply line a residential area may be developed. With regards to the environment, it is a difficult matter as large infrastructural measures always do interfere with the environment.