India’s agriculture sector has seen a record sowing of 108.2 million hectares – the highest in recent times – with great monsoons this year coupled with job losses in the organised sector due to COVID-19. The yield is expected to be much higher than usual but the price of the produce is likely to be low due to higher supply. Another reason for increased costs is that farmers are finding it difficult to source adequate quantities of fertiliser. However, these fertilisers are sold in the black market at a higher price, leaving farmers in the lurch.
Typically, around 150 kg of chemical fertiliser costing Rs 3,750 is used per hectare for crops like toor, cereals, maize and ragi. India imports about 10 million tonnes of the 26 million tonnes of fertiliser consumed every year; only around 62% is produced domestically. In this scenario, it may be prudent to consider using organic compost produced by processing municipal solid waste.
Waste as compost
Indian cities generate about 1.5 lakh tonnes of waste every day, of which only half is processed. On average, about 15,000 tonnes of good quality compost can be recovered daily by processing this organic waste, according to operative guidelines issued by the Ministry of Housing and Urban Affairs, with a yield of about 10-12%. Annually, about 7 million tonnes of good quality compost can be produced at around 12-13% yield by collecting and processing the entire quantity of 54 million tonnes of waste generated in the country.
A bag of good-quality organic city-compost costs Rs 2.50 per kg, against Rs 25 per kg of chemical fertilisers available in the market. Although organic city composed contains less nitrogen, phosphorus and potassium (NPK), the higher carbon content of around 20% will be useful for enriching soil fertility.
One tonne of organic compost per hectare receives a 50% subsidy from the government, bringing its cost to Rs 1,250. Although the quantity of organic compost used is about six-times higher than that of chemical fertiliser, the cost per hectare is two-thirds. Using organic compost could also help revive soil quality, which has deteriorated in the last four or five decades due to excessive use of chemical fertilisers. Indirectly, this could result in increased yield due to increased soil fertility.
The figures in the table are approximate, but they indicate that there is room for the production cost to be 10% lower when using organic city compost, even if the quantity of compost used is six-times higher.
At present, with only 50% of municipal waste being processed, city compost can serve only about 12% of the fertiliser requirement. But this can be doubled with processing over 90%. Urban local bodies across the country are in the process of setting up and upgrading their waste-processing facilities by availing a one-time capital subsidy of 35% provided by the Government of India and 23.3% by state governments, under the Swachh Bharat mission. These plants are currently in the tendering or construction stages, and are expected to be able to process at least 90-95% of the total waste generated by the end of 2021.
Chemicals over compost
Farmers are of the opinion that only chemical fertilisers result in good yield. So for organic compost to develop wider usage, some advocacy and behavioural changes are necessary. Venkoji Rao is one of the country’s most experienced city compost manufacturing professionals. According to him, it is difficult to sell organic city compost despite it meeting all the norms set by the Fertiliser Control Order and showing crop demonstrations within the city compost producing plants. Farmers tend to prioritise the present year’s yield over soil fertility in the long run.
Low-fertility soil needs more fertilisers, which in turn increases the cost of the agricultural produce. “City compost manufacturing plants are ready to give ‘A-grade’ un-bagged organic city compost to farmers even at Rs 1.5 per kg as bagging the compost adds nearly Re 1 per kg,” Rao said. “‘A-grade’ compost means fine quality city compost that meets all the statutory requirements but is not bagged in 50 kg bags. ‘B-grade’ compost, which meets all the NPK and carbon content parameters but has varying moisture content and does not pass through a 4-mm sieve, is available at just Re 1 per kg.”
In these uncertain times when farmers are unsure about what prices their produce will fetch, keeping production costs low is prudent. Using un-bagged A-grade or B-grade compost from city waste could reduce the production cost of agriculture by 15-20% and also enrich soil fertility in the longer run.
Pushkara S.V. works at the Indian Institute for Human Settlements, Bengaluru. He has over 10 years of experience in providing advisory services on municipal waste management to more than 60 urban local bodies across the country. He has also set up and operated one of the country’s largest waste-based composting plants in Bengaluru.