Design Study for the European Underground Research Infrastructure related to Advanced Adiabatic Compressed Air Energy Storage

The Challenge

Challenges like climate change, economic, social and sustainable development as well as security are closely linked to the energy supply of European societies. In 2009, the European Union adopted a ‘climate and energy package’ including that at least 20% of EU gross final energy consumption have to come from renewable energy sources until 2020. The challenge of RICAS2020 is given by intermittent renewable energy sources which require increased energy storage to time shift this energy to meet daily demand. As a consequence, the demand for technologies for providing and storing energy is consequently increasing.

The RICAS2020 Design Study for the European Underground Research Infrastructure related to Advanced Adiabatic Compressed Air Energy Storage (AA-CAES) will provide concepts to set-up a research infrastructure dedicated to underground storage of very high amounts of green energy. The big advantage of the new concepts will be that the underground energy storage can be performed independently from the encountered geological conditions and also at all places where high energy demand exists.

AA-CAES collects the heat produced by compression and returns it to the air when the air is expanded to generate power and thus delivers higher efficiencies via a zero-carbon process. The Design Study RICAS2020 will provide concepts on the key criteria and focus on technical, legal, institutional and financial requirements of such a research facility and will be open for the whole European Research Area, especially for all research fields close to Energy Providers and Suppliers.

Renewable Energy Sources and the Need for Storage

Renewable Energy Sources are available

  • Diurnal,
  • Seasonal
  • Intermittent

Fossil Power Plants are needed as backup

Alternatively, electricity could be stored during periods of ample availability of renewable energy

Selection of Storage Method

Optimum storage method depends on many factors

  • Cost of conversion part compared to cost of storage part
  • Geographic limitations
  • Characteristics of the renewable energy source
  • Required duration of storage
  • Amount of energy to be stored

Comparison of Battery Storage and A-CAES

  • Batteries are better suited for storing solar energy because only short periods of low electricity production have to be covered (a couple of hours during the night)
  • Compressed air energy storage is favorable for storing e.g. wind energy because longer periods of low production have to be bridged (compared to solar energy)