I. What the Sector Covers
1.1 Scale and what a house controls
A smart greenhouse uses IoT, environmental control, and AI to watch and adjust temperature, humidity, light, CO₂, and soil, to run fertigation, and to warn of pests. Protected agriculture covers about 4 million hectares, and greenhouses are a large share of that, for vegetables, flowers, and seedlings. Estimates put the yield gain at 20%–30% and the saving on water and fertilizer at 30%–50%.
The 14th Five-Year Plan for Advancing Agricultural and Rural Modernization lists protected agriculture as a priority. The Specification for Smart Agricultural Meteorological Services sets part of the build. Sensors, roll-up machines, fans, shade nets, and irrigation valves close the loop on the environment.
1.2 Rules and standards
Greenhouse Environmental Control Equipment — Part 1: General Requirements sets the equipment. NB-IoT and 4G fit houses that are spread out. Sensors have to live with high humidity and corrosion.
II. Where a Walk Down the Aisle Is Late
2.1 Someone still opening the curtain by hand
The old house depends on a person looking and switching roll-up machines and fans. Summer heat, winter cold, and a cloudy day that needs extra light will not wait. A set policy, or an AI decision, can run those devices as the readings change.
2.2 Water, fertilizer, and the power bill
Flood irrigation and fertilizer by habit waste both and salt the soil. Fertigation from soil moisture and what the crop needs at that stage supplies both more tightly. Heating and supplemental light are a large share of cost, and a tighter control loop cuts that.
2.3 Pests in a closed house
A closed house breeds pests, and they have to be seen early. A walking check covers little of it. Pest lamps, spore traps, and image recognition watch on their own. A multispectral camera reads growth and stress.
III. Where the Link Is Used
3.1 The climate loop
Sensors for temperature and humidity, light, CO₂, and soil temperature, moisture, and EC report to the controller. Roll-up machines, fans, shade nets, heating, and supplemental lights switch on a set policy or an AI decision.
3.2 Fertigation
From soil moisture, EC, and growth stage, the system opens drip lines and fertilizer pumps and sets the mix. Zones, schedules, and a remote manual override are on it. The same numbers are what a water and fertilizer review uses.
3.3 Pests and growth
Pest lamps and spore traps collect on their own. Cameras plus AI name pests and read how the crop is growing. That feeds a warning and a spray only where it is needed.
IV. Who Builds a House, and Where It Has Been Used
The chain: sensors and actuators (temperature and humidity, light, CO₂, roll-up machines, fans, irrigation) go through a gateway or controller to an agricultural cloud. One house of about 1,000 m² might hold 10–30 sensors, 5–15 actuators (roll-up, fan, shade), and several irrigation valves. 4G or NB-IoT fits houses that are apart. A house uses about 50–200 MB a month.
Where it has been used: a vegetable cooperative with 80 houses put environmental sensors, roll-up machines, and drip valves on 4G. Temperature, humidity, and light follow a set policy. Yield rose about 25%, and energy use fell about 20%. A flower site networked pest lamps and spore traps, warned 2–3 days earlier, and cut pesticide use by about 30%.
V. The Numbers, and the Standards
The set points depend on the crop. Warm crops such as tomato want a day of 22–28°C and a night of 15–18°C. CO₂ at 800–1,200 ppm supports photosynthesis. Soil EC of 1.5–2.5 mS/cm and pH 5.5–6.5 suit most crops. Sensor accuracy: temperature ±0.5°C, humidity ±3% RH, CO₂ ±50 ppm. Greenhouse Environmental Control Equipment sets the devices. Protected-agriculture IoT can follow the Specification for Smart Agricultural Meteorological Services.
VI. Terms
- EC (electrical conductivity): how conductive the nutrient solution is, which tracks its concentration.
- Fertigation: irrigation and fertilizer together, metered through the drip system.
- Supplemental light: artificial light on a cloudy day or in winter.
VII. Where It Is Heading
AI climate control decides from a crop model. Plant factories use only artificial light and stacked layers. Robots pick and inspect. The supply chain takes production data into traceability and order-based farming.
VIII. Summary
A smart greenhouse ties climate sensors, control gear, and irrigation so the house, the water and fertilizer, and the pest warning run from the readings. A stable link is what makes a scattered set of houses workable.
SimtoLink supplies 4G and NB-IoT SIM cards and communication modules for outdoor, high-humidity sites, so a protected-agriculture company can run the houses from the data.