heating hot water heat system heating water in a boiler and pumping the hot water through pipes...
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Controlling the Greenhouse Environment
HeatingHot water heat system
heating water in a boiler and pumping the hot water through pipes located in the greenhouse located under benches, low maintenance, even heat
Steam heatboilers that bring water to a boil and the
resulting steam flows through pipes in the greenhouse
HeatingUnit heaters
heat air within the unit, then blow the air throughout the greenhouse. Polyethylene tubes evenly distribute air flow, cost more to operate
Infrared heat systemsproduce heat energy that is absorbed by the
plants, media, and benches, do not heat the air, suited for high greenhouses
CoolingFan and pad cooling system
Number 1 system, based on evaporation of water, pads at one end of the house are kept wet, fans at the other end of the house pull air through the pads. Air entering the house is cooled as water in the pads evaporates.
CoolingFog systems
involve an atomizer that produces water vapor, flash evaporation of this water cools the greenhouse.
Ventsconsist of panels that
open and allow air exchange with the outside, Natural cooling
Energy CurtainAutomated systems using fabrics that can
insulate a greenhouse at night and shade the crops during the dayInstalled gutter to gutter, run by computers
Short-day curtainsSimilar to energy curtains, provides darkness
that will simulate a short-day effect.
Climate Control SystemsEnvironmental controls
Devices used to turn greenhouse systems on and off, including heating and cooling systems.
Includes:ThermostatsAnalog controlsComputer controlsComputerized environmental management
systems
Climate Control SystemsThermostats are low cost, easy to install
environmental controls.On-off thermostats control fans, heaters, and
vents with the change of temperatures.Analog controls use proportioning
thermostats to run amplifiers and electronic circuitry.heating and cooling operations are integrated
resulting in better performance
Climate Control systemsComputer controls use microprocessors to
make complex judgments based on information from a number of sensors.
Computerized environmental management systems, although expensive, are accurate and can control all the automated systems together.
Automated Systems Incorporate technological developments in
the production of greenhouse crops.Automated systems cut down labor costs Automated systems allow for larger crops
Automated Systems- Planting Automated pot fillers
used to fill pots with medium, medium is lightly packed, and the pots are stacked or move down a conveyor for planting.
Automated seederspermit the sowing of entire flats or plug trays in a
few moments, trays move down a conveyor to a germination room or move to the greenhouse
Automated transplantersremove small plants from plug trays and
transplant them directly to pots.
Automated Systems- Transporting Transporting= most labor intensive part
Conveyor belt systems are used to move plants from one area of the greenhouse to another.
Tray mechanization, has grown in popularity in the U.S.Individual trays or palletized benches that hold 100
pots or more roll on a series of rails from one area to another.
Automated Systems: Watering Spaghetti tubing
Automated system that involves small tubes connected to a main line
End of each small tube is placed in a pot, and when functioning, dribbles water onto the medium.
Allows flowers and foliage to stay dry
Automated : Watering Drip irrigation
a system like spaghetti tubing
differs = provides a slow steady drip
Used with hanging baskets
Wastes less !!
Automated: Watering Ebb and flood
Watering involves watertight benches in which pots are set
Water or nutrient solutions are pumped into the bench, the medium absorbs the water, and the water drains away.
Little water loss, nutrient levels are easily adjusted, plant foliage kept dry
Automated: Watering Capillary mats
consist of porous mats placed on a bench and wetted.
The medium in the pots absorbs the water through capillary action.
Foliage stays dry, high humidity provided
Automated: Watering Irrigation booms
Move across the entire bench and well-placed nozzles flood the pots below as they pass over the plants
Commonly used with bedding plants, plug trays, and some potted flowering crops.
Automated: Watering Overhead sprinklers
Stationary sprinkler heads placed throughout the growing space
Large amount of water in a short period of time Often used with bedding plants.
Automated: WateringIntermittent mist
systemsProduce tiny droplets in
the air for the purpose of keeping plant material wet
Commonly used in the propagation phase of production to reduce water stress on cuttings
Continuous or programmed times
Vocabulary Review1. Analog controls2. Computer controls3. Computerized
environmental management systems
4. Energy curtains5. Environmental
controls6. Fan and pad
cooling system7. Fog system8. Hot water heat
system9. Infrared heat
system
10.Polyethylene tubes
11.Short-day curtains12.Steam heat13.Thermostats14.Unit heaters15.Vents16.Automated pot
fillers17.Automated
seeders18.Automated
transplanters19.Capillary mats20.Conveyor belt
system
21.Drip irrigation22.Ebb and flood23.Intermittent mist
system24.Irrigation booms25.Overhead
sprinklers26.Spaghetti tubing27.Tray
mechanization
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