Concept
Carbon and policy credits are the money flows climate and industrial policy attaches to a product based on its emissions — production subsidies for low-carbon output, payments per tonne of CO₂ captured, carbon taxes, and tradable compliance credits. They change a process’s net economics without changing its physical operation, and their size and eligibility are tied to the product’s carbon intensity.
What they are — a family of policy-created flows conditioned on emissions performance:
They enter a model as a credit (a negative cost, or an inflow on the revenue side) or a cost, adjusting the net levelized cost without touching the gross.
Conditioned on carbon intensity. Eligibility and value key off the carbon-intensity basis — and off the policy’s own CI accounting rules, which may differ from the TEA’s boundary (specific lifecycle methods, additionality or hourly-matching for the power behind electrolytic hydrogen). A credit is earned only on the basis the policy defines.
They can be large enough to flip the ranking. Designed to close the gap between low-carbon and incumbent routes, their magnitude is often a substantial fraction of — or larger than — that gap. A clean-hydrogen credit of a few dollars per kg H₂, across the hydrogen in a tonne of ammonia, can be worth hundreds of dollars per tonne of NH₃. That scale is why they’re frequently decisive for early-stage low-carbon economics — and why how much of the cost story rests on them must be made visible.
Distinct from byproduct credits and from CI itself. A carbon/policy credit is money from policy, conditioned on emissions; a byproduct credit (see revenue and credits) is money from selling a physical co-product; the carbon-intensity basis is the measurement that gates the credit, not a flow.
A clean-hydrogen production credit can transform green ammonia’s economics. Each tonne of NH₃ embodies ~0.18 t of hydrogen (ammonia’s ~17.6% H₂ by mass); a low-CI credit of up to ~$3/kg H₂ is worth, at the top tier:
~$3/kg × 180 kg H₂/t NH₃ ≈ $540 / t NH₃— on the order of, or exceeding, the ~$800/t gross levelized cost, enough to bring the net cost near or below the conventional route. But the top tier is earned only at a low carbon intensity the plant must demonstrate under the policy’s own power-accounting rules.
Edge case: booking that full ~$540/t for the asset’s whole life ignores the credit’s sunset and hourly-matched-clean-power conditions — if it expires partway through, or the plant drops to a lower tier, the net cost reverts toward the unsubsidized ~$800/t. A model that treats the credit as permanent overstates the economics.