PROBLEM TO BE SOLVED: To provide a carbon dioxide supply system capable of enhancing the growth of agricultural crops or the like by increasing the concentration of carbon dioxide while preventing a temperature rise in an agricultural facility.SOLUTION: A carbon dioxide supply system comprises an air supply passage 10 for taking air from the outside of an agricultural facility 50 to the inside thereof, an air supply blower 11 disposed in the air supply path 10 and provided for supplying air to the air supply path 10, a combustor 12 for discharging combustion exhaust gas to the supply air passage 10, and a water spray device 35 for spraying water to the air flowing through the supply air passage 10. The air containing the combustion exhaust gas is cooled by spraying water by the water spraying device 35 and then supplied to the inside of the facility 50 to enhance the concentration of carbon dioxide in the facility 50 while preventing a temperature rise in the facility 50.SELECTED DRAWING: Figure 2【課題】農事用の施設内の温度上昇を抑制しつつ二酸化炭素の濃度を高めて農作物の促成等を図ることができる二酸化炭素供給装置を提供する。【解決手段】農事用の施設５０の外部から内部に空気を取り入れる給気経路１０と、給気経路１０に設けられて給気経路１０に空気を流す給気用送風機１１と、給気経路１０に燃焼排気ガスを排出する燃焼器１２と、給気経路１０を流れる空気に水を噴霧する水噴霧装置３５と、を有し、燃焼排気ガスを含む空気を、水噴霧装置３５によって水を噴霧することにより冷却し、施設５０の内部に供給する。これにより、施設５０内の温度上昇を抑えつつ施設５０内の二酸化炭素の濃度を高めることができる。【選択図】図２
