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Guidelines for Designing the Shape and Layout of Thermal Energy Storage (TES) Rock Caverns

열에너지 저장 암반공동의 형상 및 레이아웃 설계 가이드라인

  • Received : 2015.03.09
  • Accepted : 2015.03.27
  • Published : 2015.04.30

Abstract

Thermal energy storage (TES) is a technology that stores surplus thermal energy at high or low temperatures for later use when the customer needs it, not just when it is available. TES systems can help balance energy demand and supply and thus improve the overall efficiency of energy systems. Furthermore, the conversion and storage of intermittent renewable resources in the form of thermal energy can help increase the share of renewable resources in the energy mix which refers to the distribution of energy consumption from different sources, and to achieve this, it is essential to combine renewable resources with TES systems. Underground TES using rock caverns, known as cavern thermal energy storage (CTES), is a viable option for large-scale, long-term TES utilization although its applications are limited because of the high construction costs. Furthermore, the heat loss in CTES can significantly be reduced due to the heating of the surrounding rock occurred during long-term TES, which is a distinctive advantage over aboveground TES, in which the heat loss to the surroundings is significantly influenced by climate conditions. In this paper, we introduced important factors that should be considered in the shape and multiple layout design of TES caverns, and proposed guidelines for storage space design.

열에너지 저장은 고온 또는 저온의 잉여 열에너지를 저장하여 수요 발생 시 사용하기 위한 기술로서 에너지의 수요와 공급 사이의 불균형을 해소하고, 이를 통해 에너지 시스템의 효율을 향상시킬 수 있다. 특히 간헐적인 신재생에너지 자원을 열에너지 형태로 변환하거나 저장함으로써 에너지 믹스에서 신재생에너지의 비중을 제고할 수 있으며, 이를 위해서는 열에너지 저장 장치와의 조합이 반드시 필요하다. 지하 암반공동을 이용한 열에너지 저장은 높은 건설비용이 수반되어 그 활용이 제한적이지만, 대규모의 열에너지를 장기간 저장할 수 있는 가장 현실적인 방법이다. 또한 기후조건에 따라 외부로의 열손실이 영향을 받는 지상의 열저장소와는 달리, 열저장 지하 암반공동은 장기 운영 시 주변 암반의 히팅에 따른 열손실의 감소를 기대할 수 있다. 본고에서는 열저장 암반공동의 형상 및 다중배치 설계 시 고려해야 할 주요 인자들을 소개하고, 저장공간의 설계에 대한 가이드라인을 제안하였다.

Keywords

References

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