This post is a part of BioBiz’s Bio-CNG Perspectives.
BioBiz, a division of EAI, is a leading market intelligence & strategic consulting firm for the Indian bio-based sectors.
This blog post uses the terms bio-CNG and renewable natural gas (RNG) interchangeably.
Bio-CNG or bio-compressed natural gas, also known as sustainable natural gas or biomethane, is a biogas which has been upgraded to a quality similar to fossil natural gas and having a methane concentration of 90% or greater. As the gas is derived from natural and renewable sources, it is also termed renewable natural gas (RNG).
Introduction
The Indian government had been keen on conversion of waste biomass to bio-CNG since 2017. In late 2018, the government announced that it targets to have 5000 bio-CNG plants in India. each producing about 5T of bio-CNG a day, or about 25,000 T per day of bio-CNG or over 8 million tons per year.
While this does appear to be a very ambitious target, some quick calculations suggest that such a large target is indeed achievable.
This blog post provides a quick analysis of the potential for bio-CNG production in India from various feedstocks.
Bio-CNG potential of feedstocks
While there is a diverse range of biomass feedstock that could be used to make bio-CNG, let’s conservatively consider only the following:
- Food, fruit & vegetable waste from urban areas
- Poultry waste
- Press mud from sugar factories
We consider the above three alone as all these are available in considerable quantities, can be used in a normal digester, and are also reasonably accessible for a project developer.
Feedstock | Total accessible amount pan India (tons per day)* | Biogas potential per ton (kg) | Bio-CNG potential per ton (kg) | Total bio-CNG potential per day pan India (tons) |
Urban food waste, fruit and vegetable waste | 50,000 | 75 | 40 | 2000 |
Poultry litter | 100,000 | 100 | 60 | 6000 |
Press mud | 100,000 | 150 | 80 | 8000 |
Total | 16000 |
*: For estimates, accessibility to feedstock has been factored in; all estimates are by EAI, based on multiple sources and analyses
The above total of 16,000 tons per day constitutes about two thirds of the government’s target of 25,000 tons of bio-CNG a day.
Note that we have considered only three feedstocks, and among those too, only the accessible quantum.
There are quite a few other feedstocks that have the potential for bio-CNG production:
- Paddy straw (150 million tons per annum, about 400,000 T per day)
- Human waste from sewage treatment plants (about 150,000 T per day)
- Distillery spent wash (500,000 T per day)
- Industry / effluent waste from industries such as paper/pulp, starch, gelatin, food/beverages/diary industries, sago, and more
Each of the above has the potential to provide a few thousand tons of bio-CNG per day, with paddy straw having the theoretical potential to produce over 20,000 T CNG per day! Added to the first set of feedstocks, and these could in total provide well over 50,000 T of bio-CNG a day.
Thus, the government’s target of 25,000 T (about 10 million T per year) of bio-CNG generation per day does not appear infeasible.
India uses about 100000 T of natural gas every day (about 35 million tons per year, 2018 data), of which 50% is imported. If indeed the government’s target of 25,000 tons per day of bio-CNG generation is achieved, this alone will contribute about 25% of total consumption and 50% of natural gas imports.
Such indigenous CNG production will also save the country about $4 billion per year in foreign exchange.
Know more on how BioBiz can assist your business in your strategy for the bio-based businesses, Here