Innovations for the Power Supply
What will tomorrow's grid look like?
For some years now, the way in which energy is supplied in Europe has been undergoing radical transformation. Almost everywhere, power plants are being converted to use renewable energy – albeit at different rates. The political goal is decarbonisation of the energy supply, i.e. to phase out fossil fuels.
Efficient and flexible power grid
This has resulted in a strong push to convert power generating modules to renewable energy sources. However, the more such power generating modules are converted, the more efficiently and flexibly the power grid has to function. The challenge lies in transporting the electricity generated from renewable energy sources – most of which is produced far away from conurbations and economic centres – to consumers. To meet this challenge, new line connections need to be established. What is more, electricity from renewables is not generated when it is needed, but rather whenever weather conditions are favourable. This means that storage facilities have to be built such that the electricity generated can be stored until it is actually needed.
In addition, the electricity grid must be capable of integrating households and businesses whose private photovoltaic installations generate more electricity than is needed for their own use and which are therefore eager to feed their excess power into the grid (“prosumers”). The trends described here have fundamentally changed the requirements placed on the electricity supply system with respect to both today and the future.
Research & Development at APGAPG has been analysing these trends closely for many years, most especially our Research and Development department. Our aim is to develop innovative technology solutions that will enable the power grid to handle the planned integration of renewables.
APG is working with a number of partners on corresponding electricity storage projects – for example batteries or solutions that use chemical processes to convert surplus electrical energy into (for instance) hydrogen (power to gas through water electrolysis). This will allow the surplus energy to be stored and subsequently used for multiple purposes.
APG Innovation Project: ABS for the power grid
The growing share of energy from renewable sources in the European power supply is fundamentally transforming the situation as regards electricity transmission and distribution networks. However, power grids can only function if the supply of electricity is matched precisely to demand at all times. This equilibrium is expressed as the grid frequency. A grid frequency of 50 Hertz indicates a balanced power supply, which means the system is stable. Minor deviations from the 50-Hertz frequency are everyday occurrences for transmission system operators such as APG. One of the core tasks of TSOs is to continuously balance these deviations in the millihertz range.
With increasing variations in frequency in recent years, due primarily to the feed-in of renewable energy, the need for technical balancing mechanisms has grown. APG is therefore developing smart support systems (Advanced Balancing Systems, or ABS) for power grid operation – analogous to the ABS assistance systems developed for modern motor vehicles. Our “ABS for the power grid” project involves conducting research on intelligent battery storage systems that can help automatically balance the grid frequency. Battery storage systems are becoming increasingly important in the provision of energy as an option for storing electrical energy. The available technology in this field is already relatively advanced. What is new is the approach of using battery storage systems to provide system services for grid operators at short notice.
Just as the anti-lock braking systems used in motor vehicles serve to provide an extra layer of safety, battery storage systems make use of intelligent algorithms to very quickly detect any frequency variations unable to be fully or quickly enough balanced by the technical mechanisms in place. It is precisely these situations for which fully automated storage systems have been designed, with the aim of intervening to stabilise the grid. “ABS for the power grid” is a one-of-a-kind project in Europe that is intended to identify technology-neutral requirements for system services.
More information on the project "Project ABS4TSO" at www.energieforschung.at
Facts on the Project "ABS for the Power Grid"
May 2018 until April 2021
Austrian Power Grid
APG Research Project: thermal rating on power lines
To be able to operate its grid as efficiently as possible at all times, APG is working very hard on developing ways to optimise system operation. Concrete solutions have been provided by, for example, the “Thermal Rating” research project, which was successfully completed in 2014 and has since been successively rolled out.
The weather game
Power lines heat up as power flows through them. The stronger the flow of current, the more the lines heat up. The heat generated causes overhead conductor lines to expand, i.e. to sag more and thus come closer to the ground. To maintain the required safety distances, the conductor lines may not exceed a certain temperature. The thermal rating method developed by APG accounts for external factors such as wind speed, solar radiation and outside temperature to calculate the heat generated by the conductors. This makes it possible for more electricity to be transmitted over a particular line under appropriate environmental conditions.