Concept, principles and types of greenhouse technology

1. Session:2018-2019
By
MAGA RAM PATEL
DEPARTMENT OF RENEWABLE ENERGY ENGINEERING
College of Technology and Engineering
Maharana Pratap University of Agriculture and Technology
Udaipur - 313001
Green House Technology

2. Concept of Green House Technology
 Science of providing controlled and favorable
environment conditions for plants to grow and yield high
in all seasons.
 Creates an ideal micro climate around the plants.
 Saves crop from excessive cold in winters, from heat in
summers and from rain in monsoon seasons.
 It is a framed or inflated structure covered with
transparent or translucent material large enough to grow
crops under partial or fully controlled environmental
conditions to get optimum growth and productivity.
 The internal environment of greenhouse is controlled by
growth factors like light, temperature, humidity and air
composition.

4. Principles of protective cultivation
The sunlight comes in
the green house and is
absorbed by the crop,
floor and other objects
which in turn emit long
wave thermal radiation
The solar energy
remains trapped in the
green house
 This condition of natural
rise in green house air
temperature is utilized in
the cold regions to grow
crops successfully

5. Photosynthesis Process :-
 Photosynthesis is a process in which numerous biochemical
reactions take place.
 These occur during the daylight hours because of dependence
of photosynthesis on sunlight.
 All this activity amounts to carbohydrate production ( build up)
and storing of energy.
CO2 + WATER +LIGHT ENERGY CARBOHYDRATE + O2
Respiration Process :-
 Respiration is the other process in which biochemical reactions
are involved to break down the carbohydrate and release
energy.
 Respiration takes place in all living cells at all times.

6. Global Greenhouse effect
•The greenhouse
effect is a natural
process that warms
the earth’s surface.
When the sun’s
energy reaches the
earth’s atmosphere
some of it is
reflected back to
space and the rest
is absorbed and re-
radiated by
greenhouse gases.

8. Constituents of greenhouse environment
Greenhouse environment
The basic purpose of a greenhouse is to provide an
acceptable plant environment that contributes to a
profitable enterprise.
The microclimate of a plant is specified with respect to
light, air composition, temperature, humidity and root
media.
1. Light
Light is one of key factors in plant growth and development.
A. Factors that affect the lighting system for a greenhouse
are:
 Plant’s response to light
 Amount of light, duration and spectral requirements
 Type of light source

9.  Distribution of light in greenhouse
 Cost of lighting system(initial + operating)
B. Light source
1. Incandescent
2. Fluorescent
3. High intensity discharge lams
i. Sodium lamps (High and low pressure)
ii. Mercury lamps
iii. Metal halide

10. 2.Air Composition:- Carbon dioxide
Air has about 0.03 percent (300ppm) carbon dioxide
sufficient enough to support plant growth.
Higher CO2 concentration increases photosynthesis,
ultimately leading to enhanced yield
CO2 enrichment methods:-
1. Decomposition of straw
2. Combustion
3. Liquid CO2
4. Solid CO2

11. CO2 production from combustion of different fuels
Sr. Type of fuel CO2 yield
Kg/m3 m3/m3
1. Kerosene 2642.00 1399.165
2. LP gas 1531.16 808.073
3. Natural gas 1020.77 538.715
4. Ethanol 1369.04 725.770
5. Methanol 1050.79 561.162

12. 3. Temperature
Rising the temperature limit beyond certain level
affect other process.
Longer stems, thinner stems and smaller flowers may
also occur.
 Optimal temperature range in day is 22 °C - 28 °C
and 15-20 ° C in night.
 Mean absolute Temperature should not be higher
than 35-40 °C . In case of Tomato crop max. and
minimum required temp is 35 ° C and 15 ° C.
 Daily Insolation of 2.3 kWh/ m2 day is desirable.
 Minimum threshold for soil temperature is 15 °C for
plants such as tomato, pepper, cucumber, Melon and
beans.

13. 4. Humidity
Humidity affects leaf area development and stomatal
conductance thereby interferring with the
photosynthesis and dry matter production.
Humidity inside the greenhouse is strongly influenced
by outside humidity.
Compared to temperature it is more difficult to control.
Optimum Relative humidity is 70 -90 %.

14. Orientation
 Greenhouses should be located in order to receive
maximum sunlight's.
 Above 40 degree North latitude, an East-West
orientation works best to catch maximum light during
winter.
 Below 40 degree North latitude, orient the length of a
single width house north to south
This orientation is acceptable because the angle of
winter sun is much higher at these latitude.
 Multiple greenhouse at all latitude oriented always North
to South
This orientation avoid the shadow that would occur
from the greenhouse just to the south of it in an east-
west layout

15. Covering material used in greenhouse
(1) Glass:
• Provides good transmission of light.
• Glass transmits about 84-87% of available visible light.
• Maintenance cost is very high.
(2) Acrylic:
• It has along service life (>20 years).
• Good light transmission (81%).
• It is inflammable and expensive.
(3) Polycarbonate:
• Service life up to 10 years.
• Light transmission (77%).
• Expensive.

16. (4) Fiberglass Reinforced Plastic Panels (FRPs):
• It consists of polyester resins, glass fibers.
• Can have minor amount of other resins, stabilizers, etc.
• Service life is 4-5 years.
(5) Polyethylene:
• UV stabilized Low density polyethylene (LDPE) is used.
• It has good transmissivity (80-90%) and can be used
for 3-4 years.
• It is most widely used.
• Basic LDPE without UV stabilized last for 4-6 months.

17. Load factors for greenhouse construction
1. Dead load or permanent load
2. Crop load or imposed load
3. Snow load
4. Wind load

18. Classification of greenhouses
1. A/C to working principle
 Passive type greenhouse
 Active type greenhouse
2. A/C to Size & Structure
 Quenset type
 Curved roof type
 Gable roof type
3. A/C to season
 Winter type
 Summer type

19. 4. A/C to cost & utility
Low cost low tech
Medium tech
High tech
S.No. Type of Greenhouse Cost/Sq. meter in Rupees
1. Low cost greenhouse without fan and
pad.
300 to 500
2. Medium tech greenhouse with pad
and fan system without automation
800 to 1100
3. Hi-tech greenhouse with fully
automatic system.
2000 to 3500

20. Greenhouse applications:-
 Crop cultivation
 Utilization of crop drying
 Soil solarization
 Poultry
 Aquaculture
 Greenhouse system as solar still
 Greenhouse cum biogas plant

21. Scope of greenhouse technology
 Cultivation in problematic zones.
 Greenhouse complexes around cities.
 Export of agriculture produce.
 Greenhouse for plant propagation.
 Greenhouse technology for biotechnology.
 Cultivation of roses and medicinal plants.
 Greenhouse for employment generation and increase
in income.

22. Why Green House Yields More ?
 U.V. film does not allow harmful U.V. rays to enter the
green house thus protecting the crop.
 The use of artificial light allows photosynthesis to
continue beyond daylight hours while the use of
artificial heating allows photosynthesis to continue at
an increased rate.
 Carbon dioxide released by the plants released in night
is consumed by plants itself in the morning. Thus the
plants get about 8-10 times more food than the open
condition.
 Inside temperature is raised because of green house
effect. Long wave (IR) radiations are absorbed and
retained for longer time the greenhouse.
 Latest technologies can be incorporated to get
maximum benefits.

24. Advantage of greenhouse cultivation
 The yield may be 10-12 times higher than that of outdoor
cultivation depending upon the type of greenhouse, type
of crop, and its environmental control facilities.
 The reliability of crop increases under greenhouse
cultivation.
 Ideally suited for vegetables and flower crops.
 Year round and off season production of fruits,
vegetables and flowers.
 Disease-free and genetically superior transplants, can
be produced continuously.
 Produces free from blemishes fetching good
marketability.

25.  Efficient utilization of chemicals, pesticides to control pest
and diseases.
 The water requirement of crops is very limited and easy
to control.
 High income generation from small holdings.
 Suitable for rearing/hardening of tissue cultured plants.
 Production of quality produce.
 Reduced use of insecticides and pesticides.
 Modern techniques of hydroponic (soil less culture);
Aeroponics and Nutrient film techniques are possible
only under greenhouse cultivation.

26. “Global warming is a warning,
Stop polluting and stop harming”
Thanks for Your Nice
Attention
Looking forward for your feed back soon
M:- 9672824488, E-mail:- manishchoudhary1139@gmail.com