PURPOSES : The purpose of this paper is to investigate the application of thermoelectric technology to concrete structures for harvesting solar energy that would otherwise be wasted. In various fields of research, thermoelectric technology using a thermoelectric module is being investigated for utilizing solar energy. METHODS: In our experiment, a halogen lamp was used to produce heat energy instead of the solar heat. A data logger was used to record the generated voltage over time from the thermoelectric module mounted on a concrete specimen. In order to increase the efficiency of energy harvesting, various factors such as color, architecture, and the ability to prevent heat absorption by the concrete surface were investigated for the placement of the thermoelectric module. RESULTS : The thermoelectric module produced a voltage using the temperature difference between the lower and upper sides of the module. When the concrete specimen was coated with an aluminum foil, a high electric power was measured. In addition, for the power generated at low temperatures, it was confirmed that the voltage was generated steadily. CONCLUSIONS: Thermoelectric technology for energy harvesting can be applied to concrete structures for generating electric power. The generated electricity can be used to power sensors used in structure monitoring in the future.

최근 에너지 생산에 대한 환경적인 문제가 중요한 해결 과제로 대두 되면서, 친환경적인 에너지 생산의 중요성이 강조되고 있다. 그 중 에너지원으로 이용이 가능한 풍력, 태양열, 조력 등은 일상생활에서 쉽게 발견 할 수 있는 에너지원의 대표적인 예 이다. 특히 온도차를 전기에너지로 변환 시키는 열전효과를 이 용한 에너지 하베스팅의 경우 향후 발전 가능성이 매우 높아 자동차, 의료기기, 무선 네트워크 등 첨단산 업 분야에서 관심도가 높아지고 있지만 토목·건축 분야에 있어서는 낮은 변환효율 때문에 관심도가 높지 않은 상황이다. 그러나 토목분야에서 적용시킬 수 있는 태양열을 이용한 에너지 하베스팅은 반 영구적 이 라는 특성이 있기 때문에, 발전효율을 증가시킨다면, 경제적인 측면에서 매우 효율적일 것이다. 따라서 본 연구에서는 콘크리트 구조물의 적용되는 열전모듈의 온·냉열부 온도차를 증가시키는 방법으로, 동일조 건 하에서 열전도율이 높은 알루미늄 재질의 판을 두께에 따라 열전모듈의 온·냉열부에 압착시키는 방법 과 서로 다른 재질을 이용한 케이싱을 설치하여 발전효율을 비교 하는 방향으로 연구를 진행·분석하였다.

Thermoelectric-thick films were fabricated by using a screen printing process of n and p-type bismuth-telluride-based pastes. The screen-printed thick films have approximately 30 in thickness and show rough surfaces yielding an empty gap between an electrode and the thick film. The gap might result in an increase of an electrical resistivity of the fabricated thick-film-type thermoelectric module. In this study, we suggest a conductive metal coating onto the surfaces of the screen-printed paste in order to reduce the contact resistance in the module. As a result, the electrical resistivity of the thermoelectric module having a gold coating layer was significantly reduced up to 30% compared to that of a module without any metal coating. This result indicates that an introduction of conductive metal layers is effective to decrease the contact resistivity of a thick-film-typed thermoelectric module processed by screen printing.