In this part of the expert interviews series we interviewed DI (FH) DI Karl-Peter Felberbauer and DI Dr. Gerfried Jungmeier from the JOANNEUM RESEARCH Forschungsgesellschaft mbH
JOANNEUM RESEARCH is a company-oriented innovation and technology provider, which has been conducting top-level research on an international level for over thirty years. With a focus on applied research and technology development, it is a key player in technology and knowledge transfer in Styria.
What is the role of the development and establishment of energy storage systems in Austria in connection with the energy system of the future?
Felberbauer (F): Austria is known as the "green battery" of Europe, as we are favored by the geographic conditions of the Alps. This already results in a certain potential for pumped-storage power plants. The expansion of these existing pump accumulators is planned, or the upgrading of storage power plants without pump to pumped storage power plants. Austria will in any case play an important role throughout Europe, especially in the context of the situation in Germany, where the expansion of renewable energies is taking place very quickly.
In the low-voltage distribution network, electrochemical energy storage devices (batteries) can become increasingly important. In addition to batteries, other technologies such as flywheels or capacitors for short-term storage can also be used as decentralized energy storage technology. Important for these new technologies is the question of the implementability, or how can a technology be used, if at present the costs are not economically viable.
Jungmeier (J): In addition to the storage of electrical energy, the storage of heat (eg as warm and hot water) is an important issue. Solar energy, which can supply corresponding heat quantities, is mostly used in the summer, but is also to be used increasingly during the transitional period and in winter. A storage of the heat over several months is thus urgently necessary.
How is the storage technology in the overall system of the energy supply?
F: First of all, one must consider the following: From the economic point of view, the holistic approach is important. First, other possibilities in the overall system to increase the share of renewable energy are to be exhausted, since every use of a storage technology is associated with losses.
J: It is therefore important to use the energy when it is generated, so there are no losses and additional costs due to the storage. Thus, the subject of load shifts is a crucial one, and a use with simultaneous consumption is striking.
J: In connection with the heat storage, it is to be noted that the heating requirements of buildings are constantly going down. This means that less heat has to be stored, smaller storage volumes are required. Developments in different industrial sectors therefore run parallel and influence each other.
Where do you see the greatest storage potentials in Austria?
F: There is still potential in the field of high-tech electrical storage in the field of pumped storage. In the decentralized sector, the electrical energy storage is becoming increasingly important because of the decentralized supply of electricity from photovoltaics.
Which storage technologies are currently in use?
J: Pumps accumulators can already be shown economically well due to their good efficiency. All other new technologies in the power storage sector are associated with higher costs since the prior art is not yet fully developed.
F: In addition to the aforementioned pumped storage plants, water storage is primarily used in the thermal area. These are already state of the art. They are usually fed by solar collectors and serve as buffer storage for hot water preparation and heating support.
What are the storage technologies of the future?
J: Pumps in Austria will continue to be of great importance in the large-scale sector. In the decentralized area, the battery technology will become very important as it is very close to the application. In the area of thermal storage, the hot water storage tank will continue to play an important role, especially during heat transport from summer to winter. For large amounts of heat the technology has to be implemented even better.
F: Latent heat storage technology and thermochemical energy storage are, for example, a "novel" technology in the heat sector. These have the advantage of the higher energy density compared to conventional water storage. They are also characterized by lower heat losses because the temperature in the storage unit is constant. As more energy can be stored in less space, the application potential increases. The problem of latent heat storage technology is, among other things, the poor thermal conductivity (compared to water storage), an optimization is being carried out, among other things in Austria. The breakthrough in this area is hoped. However, research is also carried out on "classical" technologies, such as the optimization of the water storage. For example, the insulation is to be improved by vacuum technology.
In the electrical field, it is difficult to identify a storage technology that is particularly suitable because it has a very wide range of technologies with different advantages and disadvantages. Where research is being carried out is lithium-ion technology, since this technology is also an important topic in the context of e-mobility. However, it is difficult to say whether developments in the field of e-mobility batteries are entering the stationary sector.
In the large technical area, compressed air storage is also an issue. Two demonstration systems are currently being developed worldwide: diabatic compressed air accumulators.
Furthermore, hydrogen can be produced by the electrolysis by means of renewable electricity, which can in turn be stored in pressure vessels and made usable at a later stage by means of a fuel cell (eg in the car or power plant). A problem with compressed-air and hydrogen storage technology is that they are far from reaching the efficiency ranges of the pumped storage.
Another hope is the so-called "Solarfuels". The hydrogen produced by renewable electricity is methanized in an additional process step by adding CO2. The resulting methane could then be fed into the existing natural gas network or stored in existing natural gas stores. This methanation is associated with further losses, which means that even more use of renewable energy is necessary.
J: Important energy storage devices are biogenic fuels (logs, pellets, biogas, etc.). The energy chemically bound therein can be used exactly when the demand for current and heat is present. This would allow a combination of a photovoltaic system with a biogas installation. If the solar energy is not available, the biogas installation will start to power. Biogenic fuels can thus be combined well with fluctuating energy generation possibilities (sun, wind). This is an important key to our future research activities and here we are working together with the industry in the area of flexible and rapidly controllable thermal power plants.
F: Thermochemical storage (adsorption and absorption heat storage) is an alternative only in the medium to long term, as the technology is not yet fully developed.
J: Promotions would be an opportunity to push these new technologies forward. Another possibility is the increase in energy prices, which would be very effective but probably also a very unpopular measure.
What is the significance of social and ecological arguments in storage technology?
J: With regard to social and ecological compatibility, Pumpspeicher take a special position because they represent deep cuts in the landscape / ecology. All other storage technologies have little potential for conflict in this context.
F: The efficiency of the storage is important in order to demonstrate the ecological advantages, since more energy must be generated for each storage process than can actually be used due to the unavoidable losses. Of course, from an environmental point of view, there is also a difference between electricity from a coal-fired power plant and wind power.
What are the biggest challenges in storage technology?
F: It is a challenge for all storage technologies (including those already established such as pumped storage plants) to minimize the losses. It is also important to increase the energy density in order to facilitate application in practice and thus to realize new utilization potentials.
As already mentioned, in the context of the feed-in of renewable electricity into the electricity grid, first possibilities must be exhausted which are aimed at a production with simultaneous demand. In addition, the storage technologies are given a high degree of hope in order to compensate for a future network expansion. This applies in particular to the PV power fed into the low-voltage network in ever-increasing quantities. The production peak at midday could be intercepted by means of storage, which is essentially battery storage systems for storage over several hours to days. These can be placed directly at the end user or can be combined for whole settlements. Flywheel storage, on the other hand, can not store much energy efficiently over an extended period of time and is an issue for short-term electricity storage.
What are the technological advances and developments in the next 10 years
J: Due to the developments in battery technology in the field of electric mobility, we also expect corresponding positive developments in the stationary sector. Especially in terms of cost reduction and lifetime with lithium-ion batteries. It is important to drive innovation through mass production. Especially in the context of decentralized photovoltaic power generation, there can be a lot going on in the next 10 years.
In the field of heat storage, we are continuing to improve the thermal insulation of water storage with partners. To this end, we have developed a so-called "thermoscopic storage tank" with the aim of developing a good insulation which is technically easy to produce. Especially in the heating sector, hot water storage will continue to be an important issue in the future.
F: In the electricity sector, the development of intelligent networks will play a key role in storage technology and storage requirements.
J: Important in this context are the prevailing framework conditions:
These frameworks can stimulate innovation and increase the chances for renewable energy sources. This is of course also the role of the storage systems.
What measures are required by which actors to realize the potential future potential?
J: Industrial and plant engineering is required as companies are needed to build these plants (whether pumped or accumulated). Then, of course, the market and the customers are important actors, as demand can also promote technological development. In the energy sector, this adaptation to new technologies unfortunately runs slower than in other areas, eg in mobile phone technology, where considerable sums of money are spent on the latest technology. Thus a social rethinking in the area of energy supply, and thus in the energy storage area, is necessary.
How are Austrian companies involved in storage technology?
F: In the hydropower area, local companies in the component area (generator and turbine construction) are well positioned, as the topic is important in Austria, due to historical and geographic reasons. In the battery sector, there are smaller companies, which devote themselves to a special technology in the niche area and usually enter into co-operation with larger companies.
In the heat sector, Austrian companies are very well positioned in hot water storage technology.
What technologies are being researched in Austria and who are the relevant players?
F: In the field of thermal energy storage, the AIT - Austrian Institute of Technology, AEE - the Renewable Energy Working Group, and the ASIC - Austria Solar Innovation Center are to be mentioned. In the battery area the TU GRAZ is an important player, in the area of the flywheel storage the TU Vienna.
J: Projekte mit der Industrie gibt es beispielsweise mit VARTA, EVN (erneuerbare Methanproduktion).
At JOANNEUM RESEARCH, practical applied research is at the forefront. Above all the pump and battery storage tanks are interesting from the Austrian research point. Batteries are becoming more and more important especially in the context of smart grids, as there is still a lot of research to be done.
What is the current impact of electric mobility on storage technology requirements?
J: As far as the development of e-mobility is concerned, it is already a great advance over the last few years that there are now already ready-for-production electric vehicles. The question will be how the costs of this technology will develop in the coming years. This will depend on the return of innovation to stationary storage.
What is the role of storage systems internationally, for example in Germany?
F: Germany has a greater need for action because of the massive expansion of renewable energies and the resulting strain on the network. This is why research is also very interested in this topic. There are € 200 million of research funding available to support this topic. Various storage technologies, such as, for example, the compressed-air accumulator technology in development.
In summary, there are currently a few established storage technologies (pump storage, battery storage, hot water storage) and a number of other technologies, which are currently still in the research stage or test facility status. This results in many future development opportunities for domestic research facilities and technology producers.
DI (FH) DI Karl-Peter Felberbauer
DI Dr. Gerfried Jungmeier