Controlling the Temperature and Humidity in a Greenhouse

The paper presents a solution to control the temperature and humidity in a greenhouse. A previous implementation was based on the exchange of air masses between the interior and exterior of the greenhouse. But it was difficult to obtain a lower and stable inside air temperature than outside. In order to solve this problem, a solution based on water vaporization under high pressure was taken into consideration. The generator of the vapours is driven by an automated controller which measures the temperature and humidity inside the greenhouse. Yet, the solution has a drawback: because the vapour condenses on the leaf, there is a risk of infection. In order to prevent it a specific sensor for detecting the leaf wetness is used. Fans and curtains could be also used if necessary. The solution is an extension of the previous application and assures a more accurate environment for the optimal plant growth less affected by the outside weather conditions.