Günther Brauner teaches at the Institute of Energy Systems at the TU Wien and is the author of the books "Energy Systems: Renewable and Decentralized - Strategies for the Energiewende" (2016) and “System efficiency with renewable electricity generation” (2019). He is faculty member in the postgraduate MSc Program „Environmental Technology and International Affairs“, offered by the CEC and the Diplomatic Academy Vienna. In this context he regularely gives a lecture called „Energy and the Environment“ in which he teaches technological, economic and ecological topics.
In his interview he explains the potential for renewable energy in Europe and Austria, in which fields politics should set more priorities and why efficiency and sufficiency are important key words for a sustainable future.
The European Union has set itself the goal of being climate neutral by the year 2050. What are the biggest technological, political and economic challenges for the generation of climate-neutral electricity in Europe?
The economically and ecologically compatible renewable potential from wind energy, photovoltaic and hydropower is only enough for less than half of today’s demand. Therefore the development and expansion of wind energy and photovoltaic is necessary. These technologies need much space and require acceptance of the population for new onshore wind farms, photovoltaic on roof tops and the expansion of electrical grids. Furthermore, new centralized and decentralized storage capacities are necessary as well as backup power plants.
The innovation of energy systems will lead partially to unemployment in old industries and to new jobs in innovative industrial sectors. This requires a socially acceptable adaption process of some decades, not least because of high capital demand and the development of large industrial production capacities for a large number of renewable plants.
In your second book, you write that the realistic potential for renewable energy in Europe covers only 40 to 50 % of today’s energy end-use demand. Why is that and what will it take to reach 100 %?
This is a consequence of the regulations for regional planning. For instance, wind farms have to observe minimal distances to settlements and infrastructures such as airports or conservation areas. The installation of photovoltaic panels on green areas should be avoided in the future and only areas on rooftop and facades of buildings should be used. The profitability is a further boundary: a higher energy demand needs higher investments.
But the efficiency potential is large. By means of technological transition to electrical mobility and to thermal insulated buildings, a significant progress in efficiency is possible. The demand can be herewith reduced in a way that the renewable potential limits can nearly be reached. The electricity price will double until 2050, but by reducing demand according to the renewable potential, cost savings are possible, resulting in nearly unchanged energy costs for households.
You also write in your book: “Technological efficiency improvement and altered sufficient user behavior are necessary to enable a renewable energy supply”. How must we change our energy consumption behavior and which political measures are necessary?
70% of the energy transition can be reached by technology e.g. electrical mobility and energy efficient buildings and the other 30 % by sufficiency, e.g. smaller electrical cars instead of off-road vehicles or by smaller living space per person. Measures in direction of efficiency and sufficiency should be a political priority instead of the extension of renewable generation without efficiency and sufficiency improvement. This permits a socially and ecologically acceptable energy transition.
Everyone is talking about electrical mobility lately. Is the electricity grid today designed in a way that the majority of the Austrian population can connect their electrical car to the grid?
The change to electrical mobility will only need 15 % of the electrical energy demand of today. But rapid charging creates a problem, since the charging of a car today requires a high power of up to 150 Kilowatt. This high amount of energy is only needed for a short period, about 15 minutes, but can still overload the distribution grid.
In suburban local traffic, an electrical car drives an average of only 35 km per day and does not need rapid charging and can instead be charged in the evening and overnight from a normal wall socket. In long-distance traffic this is different. Since electric cars today have a range of between 200 and 400 km on a single charge, a rapid charge is necessary. In the future the electrical charging points on the Autobahn will also be equipped with batteries. They can then be charged for hours with lower power from the grid and can deliver high charging power to the vehicle in a few minutes, without overloading the grid. In the charging points old car batteries (second life) can be used.
A further demand you make in your book: “The realization of large long term storage capacities is not possible, neither from an economic nor from an environmental standpoint. Therefore centralized and decentralized short term storage capacities are necessary in order to improve the degree of utilization of renewable energy.” What do you mean by that?
Smaller storage capacities with capacities for a few hours are sufficient to balance fluctuations of renewable generation and to keep the degree of utilization high.
In renewable electricity generation from wind energy and photovoltaic, longer periods without sufficient energy generation are possible. In order to guarantee energy supply, the storage capacities must be designed for the longest possible period without energy generation. In Austria this would require expanding the pumped storage capacities by 150 times the existing ones. This is neither environmentally nor economically feasible. Furthermore in Austria we do not have enough valleys to flood in order to reach this target of storage capacities. An economically and ecologically compatible alternative is the temporary operation of highly efficient combined cycle gas turbines. In 2019, Austria has shut down the last coal-fired power plant was shut down. Since 2004 all thermal power plants have been replaced by highly efficient combined cycle gas turbines with district heating.
What is so special about the MSc ETIA compared to other postgraduate programs?
The future will require a technological understanding of systems. This will on the one hand enable a minimal use of resources in order to develop an efficient renewable energy generation and end-use and on the other hand will use recycling to make the material cycles environmentally friendly and efficient.
Besides basic technological know-how by the TU Wien, diplomatic skills are trained at the Diplomatic Academy of Vienna. The ETIA students learn to evaluate renewable generation technologies and efficiency and sufficiency measures under economic, environmental and technological aspects. Furthermore they should be able to initiate a fair mediation process for acceptance of the necessary change to a predominantly renewable energy supply. As part of MSc ETIA I give lectures in renewable energy supply including technological, economic and environmental aspects.