The case of a poly-house in Bangalore 

Poly houses too can harvest rainwater and if used through a drip irrigation mechanism much water requirement of the poly house can come from rainwater

Karnataka State

• Has the 2nd largest drought prone area in India
• 20 of 26 districts are drought prone
• Average rainfall is 600 mm
• The search is for water and food security
• Bore wells are now 400 metres deep in parts of the state
• Only 35% of the state is irrigated

Poly house

• Area 175 sq mt.
• Shade netting
• Plant spacing 30 x 60cm
• Number of plants 700
• Duration of crop 6 months
• Yield 486 kgs
• Price Rs 35 / kg.
• Total value
• Rs 17,014/-

Drip irrigation system

• Water demand
• 1000 litres per week
• 1.45 litres per plant per week
• Drip rate 2 litres/hour
• Total water demand
• per crop 30000 litres

Research results

• Rooftop rainwater incident on poly house
• 161,525 litres
• Annual water demand 60,000 litres
• Rainwater collection efficiency 87 %
• Storage requirement 5000 litres for one crop
• 15,000 litres for 2 crops

Future work

• Minimizing cost of poly house
• Multi cropping
• Techno economic feasibility for many crops
• Research results are preliminary only