Internal Carbon Price: Steering Your Low-Carbon Investments

Quick answer. An internal carbon price (shadow price) is a notional tariff that a company sets for itself to value CO2 emissions in investment and steering decisions. No single law-mandated value exists; instead, public reference points (France's tutélaire value, EU ETS market price) help construct a predictable, documented arbitrage framework.

Across the EU, companies face converging pressures: structural rises in EU ETS quota prices, the shift of the CBAM (Carbon Border Adjustment Mechanism) into definitive phase from 1 January 2026 for importers, and rising climate disclosure obligations under CSRD and ESRS E1.

For companies not directly subject to the EU ETS but exposed to carbon inflation (industrial SMEs, cleantech startups, energy-intensive services), adopting an internal carbon price enables rational steering before regulatory mandate arrives.

An internal carbon price (shadow price) is a notional tariff that a company imposes on itself to value CO2 emissions in decision-making processes. Unlike market prices (EU ETS), it is not tradable—it is a steering signal.

Three common forms exist:

1. Shadow price: Applied only to investment and project evaluation. Generates no revenue; purely a decision signal.
2. Internal carbon fee: Applied to activities or business units and recirculated (green fund, budget cuts). A real internal cost.
3. Reference value (tutélaire): Benchmark recommended by government or public bodies for policy appraisal (e.g., France Stratégie).

Public Benchmarks in France and Europe#

France: Tutélaire Value (2026)

France Stratégie's work (the Quinet report) defines the "value of climate action". This public reference stands at approximately 250 €/tCO2 at the 2030 horizon, on a trajectory set to rise sharply beyond (2050 horizon). It reflects the social cost of carbon and the public benefits of decarbonation, serves as a benchmark for the socio-economic appraisal of public investment, and is a useful anchor for companies.

EU ETS (Market Price, Variable)

EU ETS quota prices fluctuate daily. In spring 2026, prices vary with demand cycles, EU cap decisions and macroeconomic factors. A company may adopt a rolling average or forward price (e.g., next-year futures) to smooth volatility.

CBAM: Transitional and Definitive Phases

The CBAM transitional phase (1 October 2023–31 December 2025) required only reporting. The definitive phase opens on 1 January 2026: importers must be registered as authorised CBAM declarants and cover their imports with certificates, whose sale begins in 2027. In 2026, the certificate price reflects the quarterly average EU ETS price (moving to a weekly average from 2027). This creates indirect incentive for emissions-intensive, trade-exposed activities (cement, steel, electricity, fertilizers, aluminium).

1. Define Scope and Time Horizon#

Identify activities or decision categories where you apply the price:

• Investment project appraisal (equipment, process).
• Technology option comparison.
• Budget allocation to profit centers.
• Risk and resilience assessment.

Choose an aligned horizon (3, 5, or 10 years).

2. Select a Reference Base#

• Conservative approach: Adopt the value of climate action (around 250 €/tCO2 at the 2030 horizon) to anticipate future costs without market volatility.
• Market approach: Use real or forward EU ETS price. Suited to companies directly subject to ETS or heavily exposed to CBAM.
• Hybrid: Combine a base (tutélaire or market) with sector-specific or regulatory-risk adjustment factors.

3. Document and Communicate#

Record your methodology in investment policy or ESG strategy. Clear documentation aids:

• Internal audit and board approval.
• Communication to investors (impact investors, banks, insurers).
• Multi-year consistency.

4. Annual Review#

Adjust the price trajectory as regulations evolve (CSRD updates, EU ETS changes, CBAM expansion) and economic conditions shift.

Companies subject to the EU ETS. They already buy real quotas. An internal price still helps steer energy efficiency beyond minimum compliance, or evaluate quota trading impacts.

SMEs and cleantech startups. Without direct ETS or CBAM exposure, they use a shadow price to demonstrate to investors and buyers that their models withstand future carbon cost inflation.

Multinational groups. A harmonised group price may be set above the French reference (e.g., 350 to 400 €/tCO2) to reflect stricter obligations in Northern Europe or group ESG policy.

Supply-chain importers. They incorporate CBAM into risk analysis and use a price that includes CBAM certificate impact on imported material costs.

• Don't conflate internal price with market price. A shadow price is not tradable; it aids arbitrage, not treasury.
• Justify your price trajectory. Jumping from 150 €/tCO2 to 400 €/tCO2 without explanation undermines investment credibility.
• Anticipate CBAM. From the definitive phase (2026), CBAM-liable imports must be covered by certificates (purchased from 2027); failing to anticipate underestimates margin risk for upstream suppliers.
• Integrate CSRD reporting. Mention your internal price as an assumption in ESRS E1 climate reporting (scenario analysis, 1.5°C resilience).
• Avoid greenwashing. A very low shadow price (e.g., 50 €/tCO2) contradicts stated climate ambition. Ensure selected investments deliver genuine emission reduction trajectories.

Recently, a cleantech energy software startup asked us to embed a shadow price into its investor pitch. The firm offered energy-reduction solutions (software + services) with 4–5 year payback. By adopting a 300 €/tCO2 shadow price and quantifying annual avoided emissions for customers, the startup could frame carbon impact not as direct revenue, but as resilience against future energy and carbon price inflation. Investors appreciated the transparency: the business plan rested on real energy savings and was now backed by a credible climate buffer.

The example shows the value of a well-calibrated internal price: it is not marketing, but a steering instrument that builds confidence because it is documented, consistent and grounded in public benchmarks. In practice, we advise writing the methodology into a short internal note — the chosen value, its public source, the scope of decisions it covers, and the review cycle — and revisiting it once a year alongside the budget. A price that is governed, minuted and reviewed carries far more weight with a bank or an ESG assessor than a figure improvised for a single project. It also gives the finance team a stable rule to apply when comparing two investments whose only material difference is their carbon footprint.

Hayot Expertise Recommendation. If you target ESG recognition (Lucie label, Engagé RSE, EcoVadis), an internal carbon price will feature in evaluator expectations—it signals governance awareness of carbon risk. We recommend a simple, transparent methodology: a shadow price aligned with the value of climate action (around 250 €/tCO2 at the 2030 horizon) suits most SMEs. This tool fits naturally into broader CSRD climate reporting and carbon accounting that we support through our ESG and CSRD reporting service.