drip or sprinkler irrigation (drip irrigation)

Drip and sprinkler irrigation are the two precision water-delivery systems that dominate modern Indian agriculture and serve as the primary channels for fertigation — the practice of dissolving fertilizers (including liquid digestate and LFOM) in irrigation water for direct delivery to the crop root zone. Drip irrigation delivers 1–8 litres per hour per emitter directly at the plant base; sprinkler irrigation distributes 8–30 litres per hour per nozzle in overhead sprays covering 2–10 metre radius. Both achieve water-use efficiency of 70–95% versus 35–50% for traditional flood irrigation.

For CBG plant digestate, the irrigation system choice determines whether liquid output can be monetised as fertigation. Drip systems require pre-filtration to 80–120 mesh (about 130–180 microns) to prevent emitter clogging; LFOM produced by Indian CBG plants is therefore routinely filtered through screen + disc + sand filter trains before injection into drip mainlines. Sprinkler systems are more tolerant of particulates (clog only above 400–600 microns) but waste 10–30% of applied nitrogen to ammonia volatilisation from droplets in flight, particularly above 30°C ambient. Drip-fertigated digestate delivers 90–95% of applied N to the crop; sprinkler-fertigated digestate delivers 65–80%.

Indian government schemes — Pradhan Mantri Krishi Sinchayee Yojana (PMKSY), Per Drop More Crop sub-mission — offer 55% capital subsidy on micro-irrigation for small and marginal farmers (up to 75% in selected states), making drip and sprinkler economically accessible. Drip-irrigated area in India grew from 0.5 million hectares in 2005 to over 6 million hectares by 2024, with parallel sprinkler-irrigated area of about 5 million hectares. This expansion has created the addressable market for liquid biofertiliser sales. CBG plants partnering with State Horticulture Mission cooperatives and drip-installer companies (Jain Irrigation, Netafim, Finolex) frequently bundle LFOM supply contracts with system installation, securing both offtake and brand visibility.

• Precision water-delivery: drip (1–8 L/h at root zone) and sprinkler (8–30 L/h overhead).
• Drip needs filtration to 80–120 mesh; sprinkler loses 10–30% N to volatilisation.
• PMKSY subsidies 55–75% have driven Indian drip area to 6+ million hectares.
• Primary commercial channel for liquid digestate and LFOM sales from CBG plants.