Two things happened to Indian biogas within weeks. The Government set a much higher administered price for compressed biogas, and the Reserve Bank raised the repo rate. A developer with a floating-rate loan will pay more interest at the same time as it earns more for gas, so the natural question is how much of the new revenue the lender takes back. The answer, on the published numbers, is very little: the price rise is worth about fifty times the cost of the hike, for a plant that actually receives the new price. This piece shows the arithmetic, then covers the parts that decide whether a given plant gets the gain: where biogas sits in the RBI’s priority-sector rules, how its main lenders price loans, and what the price does not cover.

How much to trust it. Every figure comes from search-result summaries of press, law-firm and agency pages. The RBI, PIB and IREDA sites could not be opened from the research environment, so nothing is quoted from a primary text, and several sources conflict. The arithmetic is this blog’s own illustration, and its inputs are listed under the table. The RBI does not publish bank credit to compressed biogas at all, which is the first thing to know about “RBI data on CBG”.

The price rise: what changed

GOBARdhan, the unified scheme for compressed biogas, was approved by the Cabinet on 6 August 2026 with an outlay of Rs 23,731 crore over FY2026-27 to FY2035-36. It sets an administered CBG price of Rs 2,110 per MMBtu, excluding taxes and compression charges, held to 31 March 2036 with a Project Approval Board review every 12 months. The previous procurement price was Rs 1,478 per MMBtu, valid from June to October 2025 and itself raised from Rs 1,380 in May 2025. The jump is Rs 632, or 42.8%.

In rupees a kilogram, the reports disagree. The Government’s factsheet is reported to say Rs 105 a kilogram, while the Business Standard and the ministry’s own affordability figure imply about Rs 98 at 95% methane. The gap looks like a calorific-basis difference (roughly 20.1 versus 21.5 kilograms per MMBtu), which is not confirmed. This piece uses the lower figure: Rs 1,478 is about Rs 69 a kilogram and Rs 2,110 about Rs 98, a gain of about Rs 29 a kilogram. With the PIB basis the gain would be about Rs 32.

Two context points. The government also adds up to Rs 10 a kilogram of affordability support, which reduces what city-gas companies and consumers recover; the producer is reported to receive the full administered price. And the new price is above the pump price of CNG: Delhi’s IGL charged Rs 86.98 a kilogram after a hike on 29 August 2026, and Mumbai’s MGL Rs 88 from 1 September. That is why the scheme pools CBG with other domestic gas, with GAIL as the paying operator, instead of selling it to city-gas companies at the administered price.

The rate rise: what the RBI data show

The hike reversed a fifth of the 125 bp of cuts in 2025. Banks passed all 25 bp through to their repo-linked lending rates the next day, which is what an external-benchmark system is built to do. RBI rules, as relayed, require retail and MSME floating loans to be linked to an external benchmark and reset at least once every three months. The RBI has not published how much of the pass-through has reached outstanding loans, and the post-hike lending-rate data will not appear until about the end of October.

Priority sector lending: where biogas sits

Compressed biogas plants were added to the priority-sector list in the RBI’s 2020 review and are carried in the 2025 Directions (dated 24 March 2025, effective 1 April 2025) under agriculture infrastructure, in the indicative list of eligible activities. Priority-sector status matters because banks must lend a set share of their adjusted net credit, with targets anchored at 40%, to listed sectors, so a biogas loan helps a bank meet a target and is easier to approve. The RBI has amended the Directions three times in 2026 (19 January, 7 August and 11 September); only the January amendment, which added NCDC as an on-lending entity and updated references, could be explained, so the later changes are unread.

The agriculture-infrastructure limit has a cliff, and it sits where the economics are. Using capex of Rs 8.5 crore a tonne a day and 70% debt, the Rs 100 crore limit covers about 17 tonnes a day of CBG capacity. Industry analysis describes 20 to 24 tonnes a day as the more financially sustainable size, which would need Rs 119 crore or more of debt and, if the rule is as the RBI’s FAQ is summarised, would take the whole exposure out of the priority sector. The one large deal found, Indian Bank’s Rs 836 crore to nine IOC-GPS plants in September 2025, is above the limit as a single borrower; whether it is counted as priority sector, or each plant sits in its own borrowing entity, was not found. It is also unclear whether a bank books a CBG loan under agriculture infrastructure (cap Rs 100 crore) or renewable energy (cap Rs 35 crore); the higher cap is the likelier home, but that is inference.

There is no renewable-energy category of priority-sector lending certificate, so a lender cannot sell the status on at a premium. The four certificate types are agriculture, small and marginal farmers, micro enterprises and general, and no premium for any of them was found. The Agriculture Infrastructure Fund adds a 3% interest subvention on loans up to Rs 2 crore, which is too small for a plant, and one bank’s page lists CBG as eligible.

How CBG loans are priced, and who feels the hike

The point of the table is that “floating” covers two different things. A bank loan linked to the repo rate reprices at the next reset, and the hike reached those borrowers on 8 October. IREDA, the specialist lender, prices off its own rate card and resets annually, so a borrower on its books may see the hike only when the card is revised or the loan resets. The usual terms are 70:30 debt to equity, a tenor of up to 10 years plus a moratorium of up to one year and a construction period of up to 18 months at IREDA, and 10 to 12 years at SBI with a 30% minimum contribution. The loan is far longer than the reset period, so each reset passes any rate change through; a fixed-rate option for project loans was not found.

The arithmetic: a price rise against a rate rise

For a one tonne-a-day plant the illustration assumes: capex of Rs 8.5 crore (the published range is Rs 5 to 9 crore, from trade press quoting SBI Capital Markets); 70% debt, so Rs 5.95 crore; repayment over 12.5 years after a one-year moratorium; a bank rate of repo plus 2.65% (7.90% before the hike, 8.15% after); 330 operating days; 80% utilisation; and an operating cost of Rs 24 a kilogram, the top of one published range, assumed here to include feedstock and compression. Compression is excluded from the new price, so the comparison is on that basis.

At 80% utilisation the price rise adds Rs 77.6 lakh a year of revenue, against Rs 1.5 lakh of extra interest from 25 bp, a ratio of about 52. Debt-service cover rises from 1.25 to 2.04, and the hike on its own only takes it from 1.25 to 1.23. The price gain is equal to a rise of about 13 percentage points in the interest rate on the entire loan. The first row sits between the 1.0 to 1.2 and 1.5 to 1.8 ranges that SBI Capital Markets modelled for 6 and 12 tonne-a-day plants, which is why those inputs were chosen.

The hike does matter in one place: a plant that is already close to the line. At 50% utilisation and the old price the plant does not cover its debt service even before the hike (0.78), and the hike pushes it to 0.77. For such a plant the price rise is what could rescue it (1.27), provided it receives the new price. This also assumes costs scale with output; fixed costs would make the low-utilisation case worse.

A smaller comparison, from the same inputs: the new capital assistance, if it reduces project cost before debt is sized, cuts debt by about Rs 0.9 crore a tonne a day and saves about Rs 7 lakh a year of interest at 8.15%, nearly five times the cost of the hike. The grant is paid in stages, with the final half only at 75% of rated output, so lenders may not net it at financial close.

Where the price rise may not reach

• Existing plants. No source says whether the administered price applies to the plants already commissioned under SATAT, only to new ones, or both. If it does not reach them, they carry the higher interest without the higher revenue.
• Plants without a pipeline. Of about 130 functional plants, the regulator reports 17 connected to a city-gas network by September 2026 (later PNGRB material suggests a higher count). The price is paid by GAIL as the pooled operator, but a trucked plant still bears logistics costs the price does not cover.
• Annual review. The 10-year horizon is a framework; the Project Approval Board reviews the price every 12 months, and no escalation index was found. A lender sizing a 12-year loan cannot treat Rs 2,110 as fixed for the life of the loan.
• Utilisation and feedstock. The gain is per kilogram sold. Pressmud was reported at Rs 500 to 600 a tonne, up from about Rs 100 in two years, so feedstock costs may eat into it.

Corrections to this blog’s earlier CBG piece

This research could not confirm several details in The CBG Incentive Stack, including its 9 October update. Sources say the price took effect on 1 September 2026, with operational guidelines dated 15 September; the 1 October date for the portal launch rests on one source, and the release number cited there did not appear in any result. The capital assistance is reported as up to Rs 2 crore a tonne a day at Cabinet stage but Rs 1.25 crore, capped at Rs 30 crore a project, in the guidelines. The 80% pipeline-cost support was not found anywhere. The Rs 54 a kilogram SATAT figure is unsupported; the last official figure found is Rs 77.4 including compression, in 2025. A note on that piece is being prepared.

Where the data stop

1. No RBI data on CBG. No RBI bulletin, stability report or sectoral-deployment table breaks out biogas or biofuel lending, and no sector-wide bank-credit figure exists.
2. No primary text. The RBI Directions, the Government’s Cabinet release and factsheet, and IREDA’s rate card were read only through summaries.
3. Conflicts. Rs 98 versus Rs 105 a kilogram; Rs 1.25 versus Rs 2 crore of capital assistance; the vote on the 7 October decision (reported unanimous for the hike, with one outlet saying the stance change passed 4 to 2; the minutes are due 21 October).
4. Not found. The challenge-fund size, the credit-guarantee issuer, corpus and fee (the guarantee is reported at up to 85% for MSME CBG projects), the priority-sector sub-target percentages, any IREDA or SBI response to the hike, and the contents of the August and September 2026 amendments to the Directions.
5. Dated inputs. Capex and the debt-service ratios come from 2024 trade press, and the operating cost is a single source.

What would fix this

• The RBI should publish bank credit to compressed biogas, or to bio-energy generally, as a line in its sectoral deployment of bank credit and its priority-sector disclosures, so the sector’s debt does not have to be inferred from single deals.
• The Ministry of Petroleum and Natural Gas should state in the GOBARdhan guidelines whether the administered price applies to plants already commissioned, and print the per-kilogram figure with its calorific basis, so the Rs 98 and Rs 105 figures are reconciled.
• The RBI should clarify, for a multi-plant developer, whether the Rs 100 crore agri-infrastructure limit applies per plant company or per promoter group, since it sits at the size the economics favour.
• The Ministry should name the issuer, corpus, fee and per-loan cap of the 85% credit guarantee, so a lender can price it.
• IREDA should publish when it reprices its rate card after a repo change, so borrowers know whether a hike reaches them in one quarter or one year.
• The Project Approval Board should publish the formula it will use in its annual price review, so a 12-year loan can be sized against a known rule.

These are proposals from this blog, not recommendations any agency has adopted.

Sources and caveats

About this article: Researched, written and edited by Umashankar Triplicane Dwarakanathan, with AI research assistance; every figure is meant to trace to the primary source cited. See the Editorial Policy for how sourcing, AI use and corrections work.