Sustainability Report 2017

Interview with Dr Frank Golletz


„Sustainability involves technical aspects for 50Hertz.”“

Dr Frank Golletz, Chief Technical Officer

50Hertz has to expand its transmission system for the energy transition and in doing so wants to interfere as little as possible in nature and the environment. How do these fit together?

— Frank Golletz: 50Hertz is, first and foremost, a technology company. But the technology must be sustainably in harmony with nature and the environment. This is important to us. We have been given the task by politics and society to facilitate the energy transition with our transmission system. We also need to increase our transport capacity. This is being done, on the one hand, by optimising and strengthening existing facilities and, on the other hand, by expanding the grid. This is being done as carefully as possible with the aim of having a minimal impact on nature and the environment.

How can we visualise that?

— Frank Golletz: We have an extensive tool box with industry-standard and new, innovative technologies. So, for example, using so-called phase shifters – also known as cross-regulating transformers – we control the flow of current in our grids. Thus, the uniform utilisation of our existing grid can be controlled and power from highly loaded lines can be redirected to less loaded lines, so the existing grid is optimally used. Our tool box also includes transporting power at a higher voltage. This allows more electrical energy to be transported via existing corridors. In Saxony-Anhalt, we are currently building a pilot line that should allow the corridor for a 220-kilovolt line to accommodate a 380-kilovolt line, without the need to take up additional space. And last but not least: we are proactively building new lines. One example is the highly publicly disputed Southwest Interconnector through the Thuringian Forest Nature Park. We have designed this comparable to a four-lane highway. Currently, two tracks have essentially been released. If the need for transportation increases in the South of Germany, we will expand the Southwest Interconnector to four tracks without further intervention in nature. We will then equip the existing masts with additional lines.

Knows the grid like the back of his hand:
Dr Frank Golletz, Chief Technical Officer.

That sounds like a flexible approach to line construction. But how innovative are you regarding the further technical development of your substations?

— Frank Golletz: We are currently searching intensively for a replacement for the insulating gas, sulphur hexafluoride (SF6). Because of its good insulating properties, is has been used in high voltage switching stations for about 40 years. SF6-insulated switching stations are compact, require little space and are indispensable especially in cities. Disadvantage: The gas is harmful to the climate, increasing the greenhouse effect. A replacement gas must be much more climate-friendly with the same insulating properties. In 2019, we want to commission a switching station specifically for testing such a gas in Berlin as a pilot.

So you also economise in a sustainable and environmentally friendly manner. But adverse effects cannot be avoided entirely. What do you do in such cases?

— Frank Golletz: If we have to intervene in nature, we do so as sensitively as possible. And of course, these interventions always have to be compensated for. In order to find the right solutions, we need the support of those affected locally. We know the best technical solution, and those affected know the local area and its particular characteristics. Our aim is to bring this knowledge together to find a solution that is acceptable to all. To this end, we seek out local contacts at a very early stage, send our DialogMobil to visit, for example, and take notes from the citizens affected as well as the nature protection associations into consideration in our planning. This has resulted in a variety of measures: from the demolition of old buildings and ground unsealing to compensatory planting and bird and amphibian conservation to the restoration of entire cultural landscapes. We operate with regard for nature, the environment and people at all times.