Energy raw materials and energy storage
Energy raw materials
- Bild links oben: Geologische Formation. Bild rechts oben: Lagerstättenmodell [Quelle: Professor Leonhard Ganzer ITE]. Bilder unten: unter Tage [Quelle: Sebastian Mahr].
About 84 percent of German energy is currently generated from the fossil primary energy carriers hard coal, lignite (or brown coal), crude oil and natural gas, and a further 13 percent are generated from uranium. Both today and in the future, the research on reservoirs for all of these five energy carriers is and will be done at the Technische Universität Clausthal ("Clausthal University of Technology").
Against the background of an ever growing demand, the eventual shortage of fossil energy carriers is a predictable problem. The high price level offers incentives for intensifying the search for new deposits, for improving the output of reservoirs already discovered and for mobilising deposits already discovered but so far still without the possibility of profitable exploitation. Prerequisites for a successful fulfilment of the energy demand are thus not only qualified university graduates but also the development and refinement of new technologies. Since Niedersachsen also produces noteworthy amounts of conventional energy raw materials (with a royalty for crude oil and natural gas of approx. 450.000.000 €/a) and since it is also the home country of the greater part of the globally operative service industry for energy raw materials, it seems to make particular sense to further develop and internationalise the Clausthal site in the fields of energy-raw-material generation, reprocessing and transportation.
Apart from these activities in the conventional energy sector, Niedersachsen also focuses on research in the field of energy generation using biomass. Against the background of the pursuit of the energy-political objective of achieving in the medium term an increase of the regenerative proportion in the consumption sectors of traffic, household and small-scale consumption, which in Germany currently accounts for a mere 3 percent of the primary energy input, activities in this field reach from the mobilisation and reprocessing of biomass for energetic utilisation and the development of corresponding utilisation technologies down to the development of biogenic fuels (Biomass-to-Liquid). In the future, due to the deep-water-harbours existing in Niedersachsen, the use of biomass for energy generation in this federal state will also heavily rely on the involvement of imported biomass, which can as well be used in the form of pellets for heating purposes or – gasification – also for the generation of electrical energy or for the production of fuel.
The technologies employed in the field of energy raw materials are also a necessary prerequisite for a characterisation and use of the inner earth for other beneficial undertakings such as the use of geothermal energy or ground heat (geothermal undertakings) or the storage of harmful substances (e.g. the storage of CO2).
Energy storage reservoirs
A rising proportion of regenerative energies, but also the decoupling of energy generation and energy distribution as well as the intended shutdown of the high-output nuclear power plants, calls for the further development of energy storage for the purpose of compensating for the supply-and-demand gaps in the electrical-power network. Niedersachsen has favourable geological conditions for setting up underground storage reservoirs. On that score, the Technical Universities of Clausthal (TUC) and Braunschweig (TU BS) have put forth research works in the fields of mechanical engineering, electrical engineering, rock mechanics and petroleum geology, the objective of which consists in finding suitable locations (as the case may be also under the North Sea), in determining adequate technologies and in carrying out theoretical and experimental feasibility tests.
Smaller compressed-air reservoirs, which might make additional use of biogas as combustion gas for the application of heat at decompression, can be installed regardless of the geological basic conditions wherever there is enough space for the fitting of pipelines as pressure reservoirs. To this end, the TU BS and the TUC have already begun to carry out initial studies and experiments. For the future, a closer cooperation between the TU BS and the TUC is envisaged in the field of compressed-air storage within the framework of a project of the EFZN.
The balancing capacity and balancing energy, i.e. the so-called controlling power range and controlling energy, have to be generated not only in minute-by-minute, hour-by-hour and day-by-day intervals, but also in a matter of milliseconds and seconds (instant reserve) in order to safeguard the network stability. In this regard, the TUC is currently working on further research with the aim of combining various storage technologies (compressed air, electro-chemical storage reservoirs, flywheels, condensers and super-condensers etc.) in a way that allows meeting all the short-term requirements. At the TUB, research to this effect has already been in progress within the framework of a key project of the Federal Ministry of Economics and Technology (BMWi) since 2000, the object of this research being fast-reacting flywheel mass power storages with a minimum of no-load loss. Thus reaction rates of 2 ms and no-load loss rates of approx. 1-2 kW for storage reservoirs with an energy content of 11 kWh and a nominal output of 2 MW are absolutely feasible today.
