Greenhouse computer

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Greenhouse computers are used to create optimal growth conditions for the plants in the greenhouse . For this purpose, the most important growth factors - depending on the equipment and cultivation method, just some of these factors - are influenced by air conditioning, irrigation automation and control of fertilization. The goals are to use the computer to network as much information as possible, to use resources economically, to avoid expensive cultural mistakes and to continuously monitor the system and to protect people from accidents.

Climate computer

Climate computers in the greenhouse are connected to a weather station outside as well as sensors in the greenhouse to record the current climate values. Limit value violations and system malfunctions are monitored and trigger an alarm. The measured values are continuously evaluated by appropriate control programs. The climate factors are optimized by controlling automation devices.

Irrigation computer

Irrigation computers evaluate the climate factors in order to optimize the time of irrigation and the amount of water. In connection with systems for liquid fertilization , the water quality can be monitored and optimized by measuring the conductivity and the pH value .

Climate factors in the greenhouse

The main climatic factors that are monitored and optimized by greenhouse computers are:

  • the radiation - plants need light of the right intensity and duration;
  • the air temperature - in the greenhouse the temperatures are only acceptable through regulation;
  • the movement of air - wind can severely damage plants in the greenhouse;
  • the relative humidity - if the humidity is too high, the risk of infection through fungal attack increases;
  • the CO 2 concentration in the air - is an important factor in photosynthesis;
  • the soil moisture , or substrate moisture must be optimized for plant growth -;
  • Nutrients / liquid fertilization - can be given as part of the irrigation automation;

Weather station

The following meteorological parameters are evaluated:

  • Wind speed : cup anemometer;
  • Wind direction : Wind direction transmitter;
  • Irradiation: Luxmeter or radiation sensor for light measurement and twilight time;
  • Outside temperature: to optimize heating and ventilation and possibly cooling;
  • Precipitation: rain sensor to close the ventilation and possibly snow defrost;
  • Outside air humidity: especially for enthalpy selection program / adiabatic cooling;

Sensors in the greenhouse

In the greenhouse, sensors are used for the following measured variables:

  • Air temperature: measurement of the temperature in the vegetation, roughly in the middle of the house;
  • Floor temperature: with floor heating (prevention of overheating in the root area);
  • Air humidity: measurement of the relative air humidity in the plant stand;
  • Indoor light intensity: to optimize lighting systems;
  • CO 2 concentration: also important for compliance with MAK values for people;
  • Soil moisture: measurement in the root area of ​​the culture and possibly control of seepage ;
  • pH value of nutrient solutions: important in hydroponics and soilless culture methods;
  • Conductivity of nutrient solutions : to optimize the supply of nutrients;

Automation equipment

the climate factors are influenced by greenhouse computers using the following actuators :

Temperature control

  • Heating control: control of pumps, mixers, heating cannons, air heaters;
  • Ventilation control: control of ventilation flaps, fans;
  • Cooling : control of spray nozzles ( adiabatic cooling ) or cooling machines;

Irradiation

Humidity

  • Air humidification / spray systems: Reduction of the leaves' saturation deficit;
  • Dehumidification by cooling and heating: prevention of leaf diseases;

CO 2

  • CO 2 -Begasungsanlagen: Optimization of the CO 2 range for the plants;
  • Natural gas heating cannons: coupling of heating and CO 2 supply;

Irrigation, fertilization

  • Irrigation automation: control of pumps and solenoid valves for irrigation;
  • Fertilizer dosing systems: control of dosing systems, pumps, solenoid valves;

Buffer management

  • Storage of heat from a gas boiler that produces CO 2 for the plants during the day to use at night
  • Use of slow heating systems (e.g. wood or coal boilers) to cover the base load

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