Carbon Market Modelling
Executive Summary
Key Takeaways
- ✓ A compliance emissions trading scheme's allowance price is driven by regulated supply, typically a declining cap issued or auctioned by the scheme administrator, against demand from covered entities, and a model should represent this supply-demand mechanism rather than a generic price growth assumption.
- ✓ Voluntary carbon market price formation is driven by buyer demand for specific credit types and quality tiers rather than a regulated supply cap, producing materially different price dynamics and typically lower liquidity than a compliance market.
- ✓ Price relationships between distinct carbon markets, compliance schemes in different jurisdictions, or compliance versus voluntary markets, should not be assumed correlated, since each market's price is driven by its own distinct supply and demand mechanism.
- ✓ Regulatory change risk is a first-order driver of compliance market allowance price, since a scheme's cap trajectory, linkage to other schemes, or offset eligibility rules can be revised by the scheme administrator, and this risk should be reflected through scenario analysis rather than a single confident price forecast.
- ✓ Liquidity risk is materially higher in most voluntary carbon markets than in an established compliance market, and a model should reflect this through a wider bid-ask or execution price assumption rather than assuming an exchange-traded compliance market's liquidity applies uniformly.
Objective¶
This guide covers the market-level trading mechanics of compliance and voluntary carbon markets within Climate Finance & Climate Financial Modelling, for a financial model exposed to carbon market price risk.
Compliance Market Allowance Supply and Price Discovery¶
A compliance emissions trading scheme's allowance price is driven by regulated supply, typically a declining cap issued or auctioned by the scheme administrator, against demand from covered entities required to hold allowances equal to their emissions. A model should represent this supply-demand mechanism explicitly, tying the price forecast to the scheme's disclosed cap trajectory, rather than applying a generic price growth assumption disconnected from that mechanism.
Voluntary Market Liquidity and Price Formation¶
Voluntary carbon market price is driven by buyer demand for specific credit types and quality tiers rather than a regulated supply cap, producing materially different price dynamics: generally more fragmented by project type, vintage, and quality tier (see Carbon Credit Financial Models), and typically lower liquidity than an exchange-traded compliance market.
Cross-Market Price Relationships¶
Price relationships between distinct carbon markets, compliance schemes in different jurisdictions, or compliance versus voluntary markets, should not be assumed correlated. Each market's price is driven by its own distinct supply and demand mechanism, and a model exposed to more than one market should test each market's price sensitivity independently rather than applying a shared correlation assumption without support.
Regulatory Change Risk¶
A compliance scheme's cap trajectory, linkage to other schemes, or offset eligibility rules can be revised by the scheme administrator, making regulatory change a first-order driver of allowance price. This risk should be reflected through scenario analysis, multiple internally consistent regulatory pathways, rather than a single confident price forecast that assumes the scheme's current rules persist unchanged over the model's full horizon.
Liquidity Risk¶
Liquidity is materially lower in most voluntary carbon markets than in an established, exchange-traded compliance market. A model should reflect this through a wider bid-ask or execution price assumption for voluntary market positions specifically, rather than assuming the liquidity characteristics of an exchange-traded compliance market apply uniformly across both.
Common Construction Pitfalls¶
Generic price growth assumption disconnected from scheme cap trajectory. Fails to tie a compliance allowance price forecast to the scheme's actual, disclosed supply mechanism.
Cross-market price correlation assumed without support. Overstates diversification benefit or understates independent exposure across distinct carbon markets.
Voluntary market liquidity assumed equivalent to a compliance market. Understates execution risk on voluntary market positions.
Recommended Practices¶
- Tie compliance allowance price forecasts to the scheme's disclosed cap trajectory and auction mechanism.
- Model voluntary market price formation against credit type, vintage, and quality tier demand rather than a supply cap.
- Test each carbon market's price sensitivity independently rather than assuming cross-market correlation.
- Apply scenario analysis to regulatory change risk rather than a single confident compliance price forecast.
- Reflect voluntary market liquidity risk through a wider execution price assumption.
Continue Reading¶
Related Pillars¶
Related Technical Guides¶
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Frequently Asked Questions
What drives price in a compliance emissions trading scheme?
Regulated allowance supply, typically a declining cap issued or auctioned by the scheme administrator, against demand from covered entities required to hold allowances equal to their emissions — a model should represent this supply-demand mechanism explicitly rather than applying a generic price growth assumption disconnected from the scheme's actual cap trajectory.
How does voluntary carbon market price formation differ from a compliance scheme?
Voluntary market price is driven by buyer demand for specific credit types and quality tiers rather than a regulated supply cap, producing materially different price dynamics, generally more fragmented by credit type and quality, and typically lower liquidity than an exchange-traded compliance market.
Should carbon prices across different markets be assumed correlated?
No, price relationships between distinct carbon markets, compliance schemes in different jurisdictions, or compliance versus voluntary markets, should not be assumed correlated by default, since each market's price is driven by its own distinct supply and demand mechanism specific to that market.
Why does regulatory change risk matter specifically to compliance market price forecasting?
Because a scheme's cap trajectory, linkage to other emissions trading schemes, or offset eligibility rules can be revised by the scheme administrator, and this risk is a first-order driver of allowance price that should be reflected through scenario analysis rather than a single confident price forecast presented as if the scheme's current rules will persist unchanged.
How should liquidity risk be reflected in a carbon market exposure model?
Through a wider bid-ask or execution price assumption for voluntary market positions specifically, since liquidity is materially lower in most voluntary carbon markets than in an established, exchange-traded compliance market, and assuming uniform liquidity across both understates execution risk for the voluntary position.
References
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