Suresh MandharEmeritus Scientist

Agricultural EngineeringEmail suresh.mandhar@gmail.comPh. +919480637505, 09886385295

INDIAN INSTITUTE OF HORTICULTURAL RESEARCHHessarghatta, Bangalore - 560089

1. PLANNING THE GREEN HOUSE

REQUIREMENT

WATER

SOIL

ELECTRICITY

MARKET

WIND BREAKS

AVOID SHADING FROM OTHER GREEN HOUSES

2. TYPE OF GREEN HOUSES

NATURALLY VENTILATED

FAN AND PAD

HEATED

GREEN HOUSE DESIGNSTRUCTURE

STRENGTH AND DURABILITY

MATREIAL OR CONSTRUCTION

G.I. PIPE OR SQUARE SECTIONS

POLES

2” OR 1.5” DIA. B CLASS PIPES AT A

DISTANCE OF 2 TO 2.5 M

TRUSSES

FABRICATED FROM 1.5” G.I.PIPES

PURLINS

1 OR 1.5” G.I. PIPES

CROSS BRAZING - 1.5” TO 2” G.I.

FOUNDATION

POLE HAVING A FOUNDATION OF 60 X 60 X 60 CM OR

30 CM DIA. AND ONE METER DEPTH

1:4:8 CEMENT CONCRETE

GUTTER AND DRAINAGE

ABLE TO DRAIN RAIN WATER

GLAZING 200 MICRON UV STABILISED LDPE SHEET

SILPOLINE SHEET

FIBRE GLASS

GLASS

POLYCARBONATE GLAZING HOLDING

SHEET SHOULD BE TIGHT ON THE STRUCTURE FASTENER - SHOULD NOT TEAR THE GLAZING

3. LOCATION OF GREEN HOUSESIZENATURALLY VENTILATED GREEN HOUSE

SHOULD NOT BE MORE THAN 50 M X 50 MSPACING - NOT LESS THAN 6 M

FAN AND PAD GREEN HOUSE LENGTH SHOULD NOT BE MORE THAN 100 M

4. COOLING HEAT LOAD - SOLAR RADIATION 1kW/sq.m INSIDE THE GREEN HOUSE - 500 W / sq.m NATURALLY VENTILATED NEEDS 40 % OF THE

FLOOR AREA AS OPENING ON THE SIDES & ROOF

FAN & PAD G.H. VETILATION 2.5 cu.m. / MINUTE/ sq.m floor area

+CORRECTION FOR ALTITUDE, SOLAR RADIATION, TEMPRATURE RISE FROM PAD TO FAN G.H. LENGTH

FAN AND PAD - 12 M X 30 M NEEDS 2 FANS OF 4’ DIA UNDER BANGALORE CONDITIONS

4 FANS OF 4’ DIA UNDER NORTH INDIAN CONDITIONS

DISTANCE BETWEEN FAN AND PAD SHALL NOT BE MORE THAN 30 M UNDER NORTH INDIAN CONDITIONS

FAN AND PAD GREENHOUSE

SUITABLE FOR HOT AND DRY CLIMATES

NOT SUITABLE FOR HUMID AND COASTAL REGIONS

FASTERNER – SHOULD

NOT TEAR THE GLAZING

GLAZING SHOULD BE TIGHT ON THE STRUCTURE

FASTERNERS

SLIDING BENCHES

 Wet bulb temperature for given dry bulb temperature and relative humidity

RH (%) Dry bulb temperature 0C

10 20 30 40

20 2.5 9.3 15.7 22.0

40 4.6 12.4 20.1 27.8

60 6.5 15.1 23.8 32.6

80 8.3 17.7 27.1 36.6 

MARCH APRIL

15°C--

25°C--

35°C--

AVERAGE TEMPERATURE IN FPGH DURING SUMMER

WHEN PAD IS ON

AVG. AMBIENT TEMP.

AVG. WET BULB TEMP.

AVG. GH TEMP.

September October Nov. Dec. Jan.

22°C--

28°C--

34°C--

AVG. TEMP. IN FPGH DURING WINTER WHEN PAD IS OFF

AVG. AMBIENT TEMP.

AVG. GH TEMP.

August September October Nov. Dec. Jan.

AVG. TEMP. IN FPGH DURING CLOUDY DAYS

(WHEN FAN AND PAD WAS ON)

24°C--

30°C-- AVG. GH TEMP.

AVG. AMBIENT TEMP.

NATURALLY VENTILATED

MILD CLIMATES (UPTO 32°C)

COASTAL REGIONS

NORTHERN PLAINS OF INDIA DURING WINTER

Fan

GREENHOUSE FOR NORTH INDIAN CONDITIONS

FAN AND PAD - SUMMER

NATURALLY VENTILATED - WINTER

MULTISPAN NATURALLY VENTILATED GREEN HOUSE

0.0054 *Ag*SR * 2 AT = h * (T)1.5

Where AT= Total area for ventilation - m2

Ag= Total floor area of greenhouse - m2

SR= Maximum solar radiations received in area – Wm-2

h = Vertical distance between center of side ventilation opening and ridge ventilation opening in m

T = Difference between temperature inside greenhouse and the ambient temperature

1,00,000 LUX = 900 Wm-2

AREA FOR VENTILATION

AVG. GH TEMP

AVG. AMBIENT TEMP.21°C--

27°C--

33°C--

AUG. SEPT. OCT. NOVEM. DECEM. JAN

AVG. DAILY TEMP. IN NVGH DURING WINTER

FEBRUARY MARCH APRIL

27°C--

32°C--

37°C--

AVG. DAILY TEMP. IN NVGH DURING SUMMER

AVG. GH TEMP.

AVG. AMBIENT TEMP.

20

25

30

35

40

45

50

55

60

0

10

20

30

40

50

60

70

80

90

Ambient Temp NVGH Temp FPGH Temp Ambient RH NVGH RH FPGH RH

J A S O N D J F M A M J

Tem

pera

ture

(0 C

)

Rel

ativ

e H

umid

ity (%

)

TEMP. AND RH IN GREENHOUSES AT 10 A.M

NVGH Temp

FPGH Temp

Ambient Temp

FPGH RH

Ambient RH

NVGH RH10 A.M

20°-

30°-

40°-

-20%

-50%

-80%RH

RH

TEMP.

°C

Jul Jan Jun

20

25

30

35

40

45

50

55

60

0

10

20

30

40

50

60

70

80

Ambient Temp NV GH Temp FP GH Temp Ambient RH NV GH RH FP GH RH

Tem

pera

ture

(0 C

)

Rel

ative

Hum

idty

(%)

J A S O N D J F M A M

TEMP. AND RH IN GREENHOUSES AT 1 P.M

FPGH RH

NVGH RHAmbient RH

FPGH Temp

NVGH Temp

Ambient Temp

1 P.M40°-

30°-

40°-

20°-

-50%

-20%

-80%

°C RHRH

TEMP.

Jul Jan Jun

20

25

30

35

40

45

50

55

60

0

10

20

30

40

50

60

70

80

Ambient Temp NV G.H Temp FP G.H Temp Ambient RH NV G.H RH FP G.H RH

Tem

pera

ture

(0 C)

Rel

ativ

e H

umid

ity (%

)

J A S O N D J F M A M J

TEMP. AND RH IN GREENHOUSES AT 4 P.M

NVGH Temp

FPGH RH

NVGH RH

Ambient RH

FPGH Temp

Ambient Temp

4 P.M

20°-

30°-

40°-

°C

-20%

-50%

-80%

RHRH

TEMP.

Jul Jan Jun

0

200

400

600

800

1000

1200

10 a.m - GH-1

4 p.m - GH-11 p.m - GH- 1

10 a.m - AMBIENT

1 p.m - AMBIENT

4 p.m - AMBIENT

SO

LAR

RA

DIA

TIO

N

LU

X X

10

0

NOVEMBER DECEMBER JANUARY FEBRUARY MARCH

SOLAR RADIATION IN GREENHOUSE WITH INTERNAL SHADING AND 40 MESH

NOV. DEC. JAN. FEB. MAR.

200

400

600

800

1000

SOLAR RADIATION

INTERNAL SHADE – 40 MESH

0

200

400

600

800

1000

1200

10 a.m - GH- 21 p.m - GH-2

1 p.m GH- 2

10 a.m - AMBIENT

4 p.m AMBIENT

1 p.m AMBIENT

SOLA

R R

ADIA

TIO

N L

UX

X 10

0

NOVEMBER DECEMBER JANUARY FEBRUARY MARCH

SOLAR RADIATION IN GREENHOUSE WITH INTERNAL SHADING AND 60 MESH

NOV. DEC. JAN. FEB. MAR.

200

400

600

800

1000

SOLAR RADIATION

INTERNAL SHADE – 60 MESH

NOV. DEC. JAN. FEB. MAR.

200

400

600

800

1000

SOLAR RADIATION

EXTERNAL SHADE – 40 MESH

COMPUTERIZATION

CONTROL OF TEMPERATURE

Number of operating fans as per ambient / GH temperature

FERTIGATION

Interval and quantity of irrigation water

Quantity of fertilizer in irrigation water

SAFETY OF GREEN HOUSE

During storm close all the openings and switch on all the fans