Anyone publishing a crypto-asset white paper in the EU, and every authorised crypto-asset service provider, now has to state how much electricity the network behind each token consumes. Under the Markets in Crypto-Assets Regulation (MiCA), that is a legal requirement with a fixed template, a prescribed calculation basis and a numeric threshold that changes how much must be reported. The technical standard setting all of this out, Commission Delegated Regulation (EU) 2025/422, has been in force since 20 April 2025.
Who has to disclose, and about what
The duty sits in four places in MiCA. Persons drawing up a crypto-asset white paper must include information on the principal adverse impacts on the climate and the environment of the consensus mechanism used to issue the token: offerors and persons seeking admission to trading for ordinary crypto-assets (Article 6(1)(j)), issuers of asset-referenced tokens (Article 19(1)(h)) and issuers of e-money tokens (Article 51(1)(g)). Separately, Article 66(5) requires crypto-asset service providers (CASPs) to publish that information, in a prominent place on their website, for each crypto-asset in relation to which they provide services. MiCA says the CASP may take the information from the white paper.
The European Securities and Markets Authority (ESMA), in its 3 July 2024 final report on the draft standards, noted that "MiCA itself does not introduce exemptions from sustainability disclosures, neither related to the type, the issuance size or volume or the significance for crypto-assets, nor based on the type of crypto-asset services provided or on the significance for CASPs." The same report acknowledges one route out: Article 4 of MiCA lifts the white paper requirement altogether for small offers, such as those to fewer than 150 persons per member state or raising no more than €1 million over 12 months, and a token without a white paper carries no white paper disclosure. That does not relieve a CASP of its own website duty for the tokens it services.
What has to be reported
One indicator, by default
The mandatory key indicator, field S.8 in the regulation's template, is the total energy used for validating transactions and maintaining the integrity of the ledger, in kilowatt-hours per calendar year. The recitals explain the choice: annual energy consumption is treated as the indicator "most conducive to investor awareness", and, given the role of electricity in running these networks, electricity consumption is accepted as a proxy for it.
Five more above 500,000 kWh a year
Where that figure exceeds 500,000 kWh, a white paper must also carry five supplementary key indicators: the share of renewable energy, energy used per validated transaction, scope 1 greenhouse gas (GHG) emissions, scope 2 GHG emissions, and average scope 1 and 2 emissions per validated transaction. For CASPs the rule is narrower. The supplementary set is mandatory on a CASP's website only where the threshold is crossed and the CASP operates a trading platform or exchanges crypto-assets for funds or for other crypto-assets. A custodian, broker or adviser publishes the single energy figure unless it chooses to add more. Below the threshold, the supplementary indicators are optional for everyone, but anything disclosed must come with its sources and methodology.
ESMA's consultation had proposed ten mandatory indicators. Its final report describes the threshold as a 90% reduction in mandatory indicators for crypto-assets below it, and moving the waste and natural-resource indicators to optional as a 40% reduction overall. The reason given for that move was that those indicators depend on knowing the location and hardware of each network node, which many respondents doubted could be done reliably.
The optional tier
A third table lists indicators any firm may disclose: the energy mix, the carbon intensity of the energy used, scope 3 (value-chain) emissions, energy and emissions reduction targets, electronic and hazardous waste, total waste and recycling ratios, the impact of node equipment on natural resources, and water use.
The same rule across consensus mechanisms
The regulation does not name proof of work, proof of stake or any other design. ESMA kept what it called a "holistic approach" so that "all present and future consensus mechanisms are appropriately captured", counting the energy of the miners and validators that reach consensus. The template asks for a description of the consensus mechanism and its incentive structure, and the energy figure covers the whole network, so tokens issued on the same chain report on the same infrastructure. A white paper may take this information from another white paper for a crypto-asset issued via the same consensus mechanism.
The threshold is low. The Cambridge Centre for Alternative Finance's August 2023 revision put Bitcoin's annualised electricity consumption at 89.0 TWh for 2021 and 95.5 TWh for 2022, down from earlier estimates of 104.0 TWh and 105.3 TWh after the model's assumed mix of mining hardware was updated. That is around five orders of magnitude above 500,000 kWh. Ethereum's switch to proof of stake cut its consumption, according to the Crypto Carbon Ratings Institute figures cited on ethereum.org, by more than 99.988%, to an estimated 2,601 MWh a year in 2022. That is still about 2.6 million kWh, roughly five times the threshold. So a token issued on either network triggers the full supplementary set in a white paper; the 500,000 kWh line separates the largest public networks from smaller chains, not proof of work from proof of stake. The energy economics of mining are a separate story, covered in our piece on miners moving into AI compute.
What is settled, as of September 2026
MiCA's titles on asset-referenced and e-money tokens applied from 30 June 2024, and the rest of the regulation, including Article 66, from 30 December 2024. Under Article 143, CASPs already operating under national law before that date could continue until 1 July 2026 or until authorised or refused, whichever came first, and member states could shorten that window. That date has passed, so no CASP can still rely on the transitional regime. For crypto-assets admitted to trading before 30 December 2024, Article 143 gives trading platform operators until 31 December 2027 to ensure that a white paper exists where MiCA requires one.
The sustainability standard was drafted by ESMA in cooperation with the European Banking Authority and submitted in July 2024. The Commission adopted it on 17 December 2024 as Delegated Regulation (EU) 2025/422, published in the Official Journal on 31 March 2025 and in force from 20 April 2025. A separate instrument, Commission Implementing Regulation (EU) 2024/2984, sets the white paper templates, including a dedicated section for these sustainability indicators, and requires white papers to be drawn up in XHTML with Inline XBRL tagging. It entered into force on 23 December 2024 and has applied since 23 December 2025. We did not find an ESMA Q&A dedicated to the sustainability indicators, so firms are largely working from the regulation's text and ESMA's final report. For how MiCA compares with other jurisdictions' regimes this year, see our review of what regulators actually permitted in 2026.
How the figures are made, and where they can mislead
The regulation requires that "the methodologies used to calculate the climate and other environment-related indicators shall be rigorous, systematic, objective, capable of validation and applied continuously." Energy figures follow the calculation guidance in point AR 32 of Appendix A to ESRS E1, the climate standard of the EU's corporate sustainability reporting rules (Delegated Regulation (EU) 2023/2772); emissions figures follow points AR 39, 43, 45, 46 and 47 of the same appendix. Any deviation must be disclosed and explained. The recitals present this as consistency with the wider EU reporting framework, though many respondents to ESMA's consultation opposed using ESRS, noting that it was new even for the companies already subject to it.
Three features matter for anyone relying on the numbers. First, figures are gross: offsetting may be described separately, but its effect must not be counted in the indicators. Second, where information is not readily available, which is normal for permissionless networks with no register of node locations or hardware, the disclosure must contain estimates, marked as such, with the methodology, the main assumptions and the best efforts made to obtain better data. The name and website of any external data provider may be given. Third, if any third party verified the figures it must be named, but verification is not required. In practice, that means two firms using different data providers, or different assumptions about hardware, can publish materially different figures for the same network in good faith, much as Cambridge's own 2023 revision moved its Bitcoin estimate by roughly 9–14%.
Where the disclosures appear
For issuers and offerors, the indicators go in the white paper, in the regulation's tables and the white paper template's sustainability section, and must be reviewed and updated on a regular basis. For CASPs, the information goes on the provider's website, free of charge, as a downloadable file that makes comparison between crypto-assets easy. It must be in at least one official language of the home member state or a language customary in international finance, and, where the CASP serves a crypto-asset in another member state, also in that state's official language or a language customary in international finance. CASPs must review it at least annually, update it without undue delay after a material change with the changes clearly marked, and show the dates of publication and latest review. A CASP that relies on a white paper must name the person who drew it up as its source.
What a firm needs in place
At minimum: an inventory of the consensus mechanism behind every crypto-asset it issues or services; a measured or estimated annual kWh figure for each, tested against the 500,000 kWh line; for white papers above the line, and for trading platforms and exchange services above it, the five supplementary indicators calculated on the ESRS E1 basis, or a disclosed and explained deviation; a recorded decision on the optional indicators; a file of the estimates, assumptions, data providers and best efforts behind each figure; and a review calendar, at least annual for CASP websites. CASPs also benefit from coordinating with issuers and other platforms so that one token does not carry three different energy figures on three websites.
This is not tax, legal, accounting or investment advice, and a disclosure built for comparability is not a certificate of any network's environmental merit.