Converting Biogas to Biomethane: When It's Worth It

For a plant that is no longer eligible for the electricity incentive, switching to biomethane means upgrading the gas to grid quality and feeding it into the grid, rather than burning it to generate electricity. This is often the option that allows plants to continue generating revenue after the incentive period ends, but it is a major investment decision: a complete conversion costs millions, and the application window for PNRR support closed in June 2026. Those with a concession agreement are now building the plant according to the terms; those without one are evaluating the conversion based on the fundamentals. It isn’t a viable option for every plant: suitability comes first, then the financials.

Eligibility at a Glance
Eligibility Requirement
What You'll Need
Why does feasibility matter?
System Size and Configuration
Requirements: A staircaseand layout suitable for housing the upgrading unit
Why does feasibility come into play? Belowa certain size, the cost per Smc/h produced does not fall within
Input Matrices
What's Needed: A continuous and traceable supply chain, preferably involving waste and byproducts
Why It Determines Feasibility: Waste Streams Unlock the Highest Price for Advanced Biomethane
Distance from the gas line
What's Needed: An accessible feed-in point with an affordable connection fee
Why Feasibility Matters: Connectivity Alone Can Make a Solid Project Marginal
Investment Capacity
What is needed: Coverage of the portion not funded by the PNRR grant (up to 40%)
Why Feasibility Matters: The Cost of a Complete Conversion Runs into the Millions of Euros
Completion Timeline
What's Needed: Operationwithin approximately two years of the concession agreement, with a target date of 2028
Why Feasibility Matters: This appliesto those who have the agreement; the application period closed in June 2026

The Challenges of Conversion

Once the preliminary feasibility has been established, the economic viability hinges on a few key factors, which we will analyze using the plant’s actual figures.

Upgrading and Grid Connection

Following anaerobic digestion, the gas passes through an upgrading unit, which removes CO₂ and impurities and brings the gas up to grid quality. The upgrading unit alone costs in the range of 1–2.5 million euros, while the complete conversion of an agricultural facility runs into the millions. This is the capital investment that the return on investment must justify. The amount depends on the scale and configuration of the original facility.

Gas Line Connection

The distance from the feed-in point and the cost of the connection have a direct impact on feasibility and must be assessed first. Under ARERA’s revised regulations, a portion of the connection costs remains the responsibility of the producer. This is the factor that most often renders an otherwise sound project unfeasible, so it must be assessed before reviewing the detailed financial projections.

PNRR Incentive

The support is administered by the GSE as a subsidy: a capital grant on eligible expenses, subject to caps, plus a tariff on energy fed into the grid for fifteen years. The application period closed in June 2026, and no new application window has been announced: those with a concession agreement retain the support as long as they comply with its terms. Waste-derived biogas falls under the category of advanced biomethane, which is more heavily rewarded in the economic model. For more details, see the biomethane incentives page.

Timeline and Implementation

The window for concession agreements closed in June 2026: each agreement allows for approximately two years before the project becomes operational, with an actual timeline around 2028. Permitting, grid connection, and construction must be completed within those timeframes, as any delay could result in the loss of support. For those without an agreement, the viability is assessed based on key factors: guarantees of origin, the renewable gas market, and a comparison with the BIO-PMG.

Matrices and Sustainability

The availability, continuity, and traceability of feedstocks determine both the yield and eligibility for the advanced biomethane category—which is produced from waste and byproducts and commands a higher price. This is an issue that must be resolved before making the investment, as it affects the income statement throughout the plant’s entire lifespan.

Business Plans and Value Beyond Incentives

Subsidies, tariffs, operating costs, and long-term value—from guarantees of origin to the transmission market—determine a project’s bankability. We develop and test the financial models because that is what a bank or investor looks at before committing, and because the market value of renewable gas remains over the long term—beyond fifteen years.

What do we look at to make a decision?

Ultimately, conversion is or isn't worth it for a few fundamental reasons.

Cost-effectiveness compared to BIO-PMG

How much more does converting yield compared to staying on the minimum benefit, over a period of several years?

Bankability

The soundness of the financial statements, contracts, and hedges is what makes the project bankable.

Risk of Delays and Lapse

The realistic likelihood of meeting the terms of the support without losing the incentive.

Value Beyond the Incentive

What Remains After Fifteen Years: Guarantees of Origin and the Renewable Gas Market.

Based on our findings

Ortofoto aerea di un impianto biogas con digestori, vasche e platea della biomassa
Ortofoto di rilievo: impianto biogas
Prospetto CAD di un impianto biogas ricavato dal rilievo: digestori e coperture
Prospetto CAD da rilievo

How We Support You

We conduct a technical and economic assessment of the conversion, verify its feasibility and timeline, and, if the project moves forward, we oversee its implementation through to operation, ensuring compliance with the terms of support for those with a concession agreement—all handled by the same team that conducted the assessment.

Let's talk about it

A First Reading of the Conversion.

Tell us about your system: size, valves, and distance from the gas line. We’ll respond with an initial technical and economic assessment—provided confidentially—that evaluates the feasibility and cost-effectiveness of the conversion.