Because the inner environment of greenhouse has a direct impact on crop production, many studies have been performed to develop technologies for controlling the environment in the greenhouse. However, it is difficult to apply the technology developed to all greenhouses because those studies were conducted through empirical experiments in specific greenhouses. It takes a lot of time and cost to develop the models that can be applicable to all greenhouse in real situation. Therefore studies are underway to solve this problem using computer-based simulation techniques. In this study, a model was developed to predict the inner environment of glass greenhouse using CFD simulation method. The developed model was validated using primary and secondary heating experiment and daytime greenhouse inner temperature data. As a result of comparing the measured and predicted value, the mean temperature and uniformity were 2.62°C and 2.92%p higher in the predicted value, respectively. R2 was 0.9628, confirming that the measured and the predicted values showed similar tendency. In the future, the model needs to improve by applying the shape of the greenhouse and the position of the inner heat exchanger for efficient thermal energy management of the greenhouse.
A new design concept for integrated thermal energy storage system is suggested to increase energy saving rate for heating and cooling system of the closed glass greenhouse. Heat pump of air source is installed in the mechanical room and air flows then controlled by damper system located between the greenhouse and outdoor environments. A damper control algorithm is designed to enhance the usage of excessive energy in the glass greenhouse. Since the proposed system is installed at the actual glass greenhouse site for experimental verification of energy savings, the proposed system with damper control is compared with conventional greenhouse heating and cooling system. From results, it is found that more than 10% increase of energy saving rate is achieved.
간척지에서 대단위 유리온실 단지 조성에 대비하여 현장에서 필요한 기술을 개발하고자 전북 부안군 계화면에 벤로형 고측고 유리온실을 설치하여 파프리카를 품종별로 재배하여 일반농가와 생육과 수량을 비교하였다. 재배방식은 행거식 벤치시스템을 사용하여 암면 수경재배를 실시하였으며, LPG를 연소한 액화탄산가스를 낮동안 평균 500~600mg․L-1이 되게 공급하였고, 수평식 지열히터펌프를 활용하여 주로 야간에 22~24℃ 이하가 되도록 온도를 관리하였다. 양액의 관리는 순환식 시스템을 이용하였으며, 누적일사량 500J 마다 공급하여 배액을 20~40% 정도 유지하게 하였다. 재배기간 동안 칠레이리응애 등 9종의 천적을 응애, 진딧물, 총채벌레, 가루이, 나방류가 발생이 확인될 때 투입하여 무농약으로 재배하였다. 농가에서 많이 재배되는‘쿠프라’,‘콜레티’,‘부기’의 3품종을 재배한 결과 10a당‘콜레티’의 수량이 가장 많은 21.18ton,‘쿠프라’가 18.54ton,‘부기’가 15.45ton 순이었다. 경남과 전북의 일반농가와 10a당 수량을 비교한 결과 함안농가는 14.52ton, 창원농가는 20.89ton, 김제농가는 16.21ton을 각각 수확하여 수량성은 큰 차이가 없었다. 월별 수량을 비교한 결과 1그룹이 수확되는 12월에 수량이 높았으나, 1월에 감소한 후에 일사량이 많아지는 7월까지 증가하였다. ‘쿠프라’품종에 대하여 생육상황을 일반농가와 비교한 결과 평균 분지길이(방아다리)는 경남 창원의 유리온실에서 가장 짧았고, 경남 함안의 비닐하우스에서 재배한 경우 계화도의 유리온실과 비슷하게 길었다. 초장과 마디수는 계화도 유리온실에서 가장 양호하였으나, 착과수는 전북 김제의 유리온실에서 가장 많은 19.6개/주 정도였다. 이상의 결과로 볼 때 전북 계화면 간척지에서 유리온실을 설치하여 파프리카를 재배할 경우 다른 농가와는 큰 차이 없이 수량을 확보할 수 있었고, 천적을 활용한 무농약 재배 및 순환식 수경재배가 가능하였다.
The whole world concentrates on the reduction of greenhouse gas to effectively cope with policy toward global climate change. To effectively react to climate change, even the agricultural sector requires construction of new farming systems that utilizes new and renewable energy because of rising oil prices and regulations for greenhouse gas emissions. For this reason, we need to fuse the new and renewable energy with the horticulture sector of which the light and heat energy cost accounts for great part, moreover, efforts and researches should me done which can increase income of farmers through reducing carbon dioxide and energy cost in agricultural production expenses. Therefore, this study analyzes economic feasibility and applicability of fusing geothermal heat pump and solar power facilities with high-tech glass greenhouse. As a result, it is concluded that there surely are an applicability and economic feasibility if we apply new development system that can be an alternative for problems of securing premises of existing geothermal heat pump and the RPS system as a power generation company in case of solar power. Therefore, using this analysis data, if new empirical studies fusing and implementing agriculture sector with new and renewable energy fields proliferate and be applied to actual rural and agricultural field, it will increase actual income and will become a new advanced agricultural system that effectively deals with world-wide environmental problems.
The aim of this study is investigated greenhouse gas emissions of glass industry, and when calculates greenhouse gas emission, using formula(Tier 3) advising in IPCC(Intergovernmental Panel on Climate Change) and using self designed formula(Tier 3+) authors of this study. Studied to propose calculation formula that can compare these two calculation results and apply to domestic. Formula of Tier 3 calculated to theoretical composition of carbonate material, And Formula of Tier 3+ calculated on the basis of chemical substance formation table that get from glass manufacture company(The S company). As a result, Dolomite, Soda ash, Limestone, Industrial Barium carbonate is calculated value of Tier 3+ lower than value of Tier 3, And Industrial Potassium carbonate, Industrial Strontium carbonate was calculated value of Tier 3 lower than value of Tier 3. This study finding, formula of Tier 3+ has higher confidence than formula of Tier 3 when consider revision about purity of injection raw material. And hereafter, When calculate greenhouse gas emissions about nonmetallic mineral industry, use of Tier 3+ is considered that should be encouraged.