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Most of the automated greenhouses available in the market are expensive and are built for mass agricultural purposes and the design changes according to the plants grown inside. Some of the green houses available in the market are listed bellow.
Some of the prices of greenhouse systems are as follows
Since automated greenhouses in the market are application specified and expensive there is need for a simple automated system to control basic physical factors like temperature, soil moisture, light intensity, etc. Therefore an automated system is designed to control these three physical factors temperature, soil moisture, and light intensity inside a greenhouse in a way that a person interested in a small house could afford it.
A prototype of the system is designed using a microcontroller as the main processing unit of the system where to it soil moisture sensor, LDR and a temperature sensor are connected. Data from the sensors are processed and actuators (heater, cooler fans and bulbs) are used to control the three physical factors. So the report gives in detail why such a control system is designed and how it is designed and discusses the practical aspects and implementation issues of the developed system.
It had been identified that the rate of photosynthesis depends on the amount of light energy falling on to the leaves as light intensity reduces the photosynthesis rate reduce and respiration rate increases therefore to get the maximum out of the plants food production the photosynthesis rate needs to be kept high in day time but it is impossible to control if the plant is grown outside a greenhouse. Moreover it is to be advised that keeping the photosynthesis rates high even at night causes the plants to grow weak therefore photosynthesis needs to be controlled in day time only. Temperature of the atmosphere can drop to values below the optimum temperature and reduce the rates of plants’ respiration and photosynthesis rates and when the temperature keeps at a dropped value from the optimum value the yield would be less if the plants are subjected to natural environmental conditions. It is to be understood the terms photosynthesis and respiration. Photosynthesis is the process by which food is made by plants. They absorb CO2 and H2O from the atmosphere and uses light energy to convert them to glucose molecules and store as glycogen. Oxygen is formed as a by-product in this process. Respiration is the process by which food (organic molecules) is broken down to release CO2, H2O and energy. These processes depends uses enzymes for the operations and the enzymes depend on temperature. At high temperature around 50◦C the enzymes are denatured and at low temperatures they are inactive. Therefore controlling temperature is an essential need in a greenhouse. Due to the above mentioned processes in a plant a need for a controlled temperature, light intensity and soil moisture level is required and it is has to done by an automated system.
Many automated greenhouses available in the market are designed for commercial purposes as described in Introduction and expensive and normal person who loves gardening may not be able to afford one of those.
The other problem is that those greenhouses have so many advanced features where it might not suite a normal greenhouse that a person need to have in the garden since some of the factors. Such advanced features are controlling the carbon dioxide level in the greenhouse, providing PC interfaces etc. these features are too expensive and may not have a significant effect on a small greenhouse in the garden and therefore a simple, cheap greenhouse is the requirement for a greenhouse at the garden or the backyard.
A normal person who does gardening might not be able to water his plants daily and might worry about things like not being able to grow his/her plants under conditions (temperature, soil moisture, etc.) that they grow well so a need for a temperature control system arises.
The space available in the garden also needs to be considered when the user is to buy a greenhouse. Most of the automated greenhouses are in large scale and are designed for mass agricultural purposes hence they consume lots of power for heaters cooler fans etc. There are small automated greenhouses available that are more advanced and used for research work. There are some small automated greenhouses that control temperature by opening a hatch at the roof but in such greenhouses more work has to be done in plants like watering them at regular times maybe daily or twice a day depending on the plants grown inside. Due to these reason a control system to suite a small greenhouse is needed.
Many gardeners love to grow various kinds of flower plants but only some really blossom due to the unique conditions in which they prevail. Some seeds require temperatures from 15◦C to 20◦C to germinate and such conditions cannot be provided outside in the normal atmospheric temperature in some areas of the country.
Due to the above mentioned various reasons a need for an automated greenhouse system arises and the greenhouse system should be cheap, and needs to control the environmental conditions effectively to support efficient plant growth.