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Environmental & Waste

Anaerobic digestion

An interactive economic model of an anaerobic digestion plant — watch feedstock tip in, digesters bubble biogas and biomethane flow to the grid, see the gate-fee vs green-gas split, and run the investment case live.

Interactive model
Environmental & Waste · Anaerobic digestion

What an AD plant earns — gate fee plus green gas

An anaerobic digestion plant is paid a gate fee to take food and farm waste, then digests it to produce biomethane it injects to the gas grid (or burns in a CHP engine) — typically earning a green premium via support schemes — and sells the leftover digestate as fertiliser. The gate-fee leg is a contracted feedstock annuity; the gas leg carries price risk (offset by green-gas support). The case turns on the plant's capacity, the gate fee, and the green-gas price.

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£45
£70
LIVE
Gate fee paid per tonne of feedstock in Biogas digesters bubble biogas Green gas to grid biomethane injected (+ digestate) Operating cost feedstock, O&M, digestate
Flows — annualised from current assumptionsper year
Revenue p.a.
£0
£0 / hr
EBITDA p.a.
£0
0% margin
Revenue / tonne
£0
gate + gas
Feedstock processed
0
15 MW biomethane
Stocks — what the flows accumulate intolive
Green gas · session
0
at 15 MW
EBITDA banked · session
£0
accumulating in real time
Implied enterprise value
£0
at 10× EBITDA
Where revenue comes from Total £0 p.a.
Gate fees
Green gas & digestate
Why investors like AD: two complementary income legs — a contracted gate fee for taking food and farm waste, and green-gas revenue that often comes with long-term, inflation-linked support, giving more visibility than pure merchant power. It is genuinely green (diverting organics from landfill) and modular. The risks are feedstock (securing enough good-quality waste at the right gate fee) and biology — digesters are living systems, so plant availability and yield depend on keeping the bugs happy.
Revenue streams£0 p.a.
Operating costs£0 p.a.
Investment case — should you buy it?DCF returns

Year-1 financials flow live from the simulation above: revenue £0 and EBITDA £0 p.a. Set your deal terms below — the unlevered IRR (asset return) and levered IRR (return to equity, after debt) recompute instantly.

Operating

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Valuation & hold

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y

Financing

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Unlevered IRR
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asset / project return
Levered IRR
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return to equity
Equity multiple
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MOIC over hold
Equity gain
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exit equity − invested
Equity cash-flow profile£m · ■ invested   ■ returned
Projection — £m per year

Illustrative model. Represents a food/farm-waste anaerobic digestion plant producing grid-injected biomethane. Revenue = gate fees (tonnes × gate fee) + green gas (tonnes × biomethane yield per tonne × price, inclusive of green-gas support) + digestate sales. Operating costs (feedstock handling & pre-treatment, plant O&M, digestate handling per tonne, plus fixed labour and insurance and a maintenance reserve) leave a moderate margin that improves with scale. The gate-fee leg is a contracted feedstock annuity; the gas leg is part-merchant, part-supported. EBITDA = revenue − operating costs; excludes upfront construction capex. The investment case is a simplified DCF. For illustration only — not investment advice, and not any specific asset.