CertificAhorro
CertificAhorro
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Closed beta·The first secondary CAE marketplace in Spain, currently in development·Request an invitation

CAE Market · How it works

How does the CAE secondary market work?

5 phases, from order publication to SEPA settlement. No hidden intermediaries, compliant with Real Decreto 36/2023 and Orden TED/815/2023.

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When is the secondary market used?

The secondary market for Certificados de Ahorro Energético exists to solve a very specific problem: once the CAE is issued, the Sujeto Delegado needs to monetise it and the Sujeto Obligado needs to acquire it to meet its annual savings obligation.

The typical chain is as follows. A Sujeto Delegado (SD), accredited by MITECO, promotes energy efficiency actions, calculates the savings using the IDAE standardised data sheets, submits the S1 form on the Sede MITECO and obtains a favourable resolution from the Gestor Autonómico. The CAE is then registered in the Registro Nacional (SIICAE). In parallel, a Sujeto Obligado (SO) is subject to an annual savings obligation set by MITECO under the Ley 18/2014 and RD 36/2023, and must present enough CAE each year to the Fondo Nacional de Eficiencia Energética.

The secondary market connects both profiles within a transparent order book, replacing bilateral OTC negotiation with an audited and standardised process. The legal basis for the sale is set out in Art. 8 of RD 36/2023 (CAE as tradeable movable assets) and in Art. 17.2 of Orden TED/815/2023 (sale authorised by the certificate holder).

Unsure about the terminology? Check the CAE secondary market glossary, with more than 50 terms explained.

The 5 phases of the transaction cycle

From order publication to SEPA settlement, the process is designed to be verifiable, reproducible and compliant with current regulations.

  1. Publication (continues)

    Order in the book with volume, price and term

  2. Matching (continues)

    Price-time priority and wash trading control

  3. eIDAS signature (continues)

    DocuSeal contract with SHA-256 audit trail

  4. Transfer (continues)

    Registro Nacional MITECO, CAE in transit

  5. Settlement

    Direct SEPA payment and Facturae 3.2.2 invoice

01

Order publication

The initial phase is opened by the selling Sujeto Delegado (who lists an already registered CAE for sale) or by the buying Sujeto Obligado (who publishes a demand to cover its annual obligation). To publish, the organisation's KYC must be validated: a current MITECO accreditation, the legal representative's identity document and the CIF.

The order is published in the order book, stating volume, price (limit or market) and validity term. The minimum volume is 30 MWh per transaction (Art. 8 RD 36/2023). The seller certifies through a sworn statement that the CAE is registered in MITECO's Registro Nacional and free of encumbrances; the statement is reinforced by a penalty clause of 150 % of the amount in the event of misrepresentation, in accordance with the v2 sale contract. Orders are visible to all accredited operators; sensitive commercial data (the identity of the parties) remains anonymised until matching.

02

Supply-demand matching

The order book applies a price-time priority algorithm (FIFO within the same price level): the best offer and the best demand match first, and at equal prices the order published earlier takes precedence. When an offer and a demand coincide in price and volume (or are compatible with fractioning), a provisional transaction pending signature is generated.

The platform also integrates a statistical anti-manipulation detection module (wash trading detection) that inspects suspicious patterns of related counterparties before confirming the match. The goal is to preserve the integrity of the price index published at /mercado-cae/precios.

03

Electronic signature of the contract

As soon as a provisional transaction exists, the platform automatically generates the sale contract in accordance with Art. 17.2 of Orden TED/815/2023. The document includes the identification of the parties, the unique CAE identifier, the agreed volume and price, the sworn statements with the 150 % penalty clause and the applicable particular conditions.

The contract is sent via DocuSeal to both legal representatives for a simple electronic signature (SES) compliant with Regulation EU 910/2014 (eIDAS), Art. 25. Each signature leaves a complete audit trail with SHA-256 hash, timestamp, IP and event sequence. The typical signing period is 48 hours; the maximum term is configurable in the order and its expiry automatically cancels the provisional transaction.

04

Transfer before MITECO

After the contract is signed by both parties, the selling Sujeto Delegado initiates the request to transfer the CAE before MITECO's Registro Nacional, following the official change-of-ownership procedure. The term estimated by the sector is 5 business days until effective confirmation, although it may vary depending on the Registry's workload (sector estimate, not guaranteed by the platform).

During this period, the CAE remains in transit: the transferring SD cannot resell it because the platform automatically freezes it in the order book. This freeze is a key operational control: it prevents the double sale of the same CAE and replaces the function a traditional escrow would serve in other financial markets.

05

SEPA settlement

Once MITECO confirms the effective transfer of the CAE to the new holder, the platform issues the payment instruction. The SEPA payment is made directly between the parties: the buyer pays the seller the agreed amount according to the bank details in the contract. CertificAhorro does not intervene in the CAE fund flow.

Regarding the commission, HM Capital SARL (publisher of CertificAhorro) issues two separate invoices: MKT-S to the seller and MKT-B to the buyer. The format is XML Facturae 3.2.2 compliant with the Ley 18/2022 (Crea y Crece), accompanied by a styled PDF. As HM Capital SARL is a French entity, the invoices are issued under reverse charge: without French VAT and with an express reverse-charge mention in accordance with Art. 84.Uno.2 of the Ley 37/1992 and Art. 196 of Directive 2006/112/CE. The Spanish client self-assesses the 21% VAT in modelo 303.

Three use cases

Illustrative examples of the most frequent paths, with commissions calculated on the published grid. Prices are indicative; the real price is formed in the order book.

A

An SD sells 500 MWh after issuance

  • Context: an energy manager specialised in industrial lighting (IND050 data sheet).
  • Action: publishes 500 MWh at 125 EUR/MWh.
  • Matching: 3 SO demands match at the published price.
  • Timing: signature in 24 h, MITECO transfer in 5 business days, SEPA payment on day 8.
  • Gross revenue: 62 500 EUR. Seller commission, Delegado plan (0.15 %): 93.75 EUR. Net: 62 406.25 EUR.
  • OTC alternative: sector estimate of 1.5 % to 3 % intermediary fee, that is 937 to 1 875 EUR of broker commission.
B

An SO buys 2 000 MWh for 2025

  • Context: an electricity supplier with an annual savings obligation.
  • Action: publishes a demand for 2 000 MWh with a limit price of 135 EUR/MWh.
  • Matching: 4 SD aggregate the total volume, each fraction above the 30 MWh minimum.
  • Advantage: price discovered transparently versus case-by-case bilateral negotiation.
  • Buyer commission according to the 12-month volume tier published in the grid.
C

Installer with a small CAE file

  • Context: an installer who works with a Sujeto Delegado and wants to monetise a small batch of CAE.
  • Regulatory limit: cannot access the secondary market directly (Art. 6 RD 36/2023; MITECO doctrine after 15/12/2024 limits the chain to 1 intermediary).
  • Alternative: sells its batch to the SD through a collaboration contract; the SD publishes the order in its own name in the book.

Frequently asked questions

Answers to the operational questions that arise most frequently during the transaction cycle.

Can I withdraw a published order?

Yes, as long as the order has not been matched with a counterparty. Once the provisional transaction is generated, withdrawal requires the express agreement of both parties or the expiry of the maximum signing period without a signed contract.

Who initiates the transfer before MITECO?

It is managed by the selling Sujeto Delegado, holder of the CAE until effective transfer. Any fees are borne by the applicant unless otherwise agreed in the order. The procedure follows the official flow of the Registro Nacional of the Sistema CAE.

What happens if the buyer does not confirm the contract?

The signing period configured in the order defines the deadline. If either party fails to sign before the deadline, the transaction is automatically cancelled and the CAE volume becomes available again in the order book.

When can I sell a newly issued CAE?

From its registration in the Registro Nacional de CAE by MITECO, after a favourable resolution from the Gestor Autonómico. The CAE is valid for three years from the date of issuance.

Is there a payment guarantee escrow?

In the current version of the platform there is no escrow. Integrity is ensured through the automatic freezing of the CAE during the MITECO transfer process and the contract signed with an eIDAS SES signature (Regulation EU 910/2014, Art. 25). The SEPA payment is executed directly between the parties after the transfer is confirmed.

Can operations be fractioned?

Yes. A sell order can be matched with several buy demands as long as each fraction respects the minimum volume of 30 MWh per transaction (Art. 8 RD 36/2023). The matching algorithm generates as many transactions as fractions, each with its own contract and invoice.

What happens in the event of a dispute over the transaction?

The platform provides a formal dispute flow accessible from the transaction panel. Opening a dispute freezes settlement until resolution in accordance with the Market Terms and Conditions in force, by submitting the supporting documents (signed contract, CAE traceability, communications).

What about the VAT on the commission?

HM Capital SARL, publisher of CertificAhorro, is established in France. The commission invoices to the seller and the buyer are issued under reverse charge in accordance with Art. 84.Uno.2 of the Ley 37/1992 and Art. 196 of Directive 2006/112/CE. The Spanish client self-assesses the 21% VAT in modelo 303.

Closed beta · Access by invitation

Take part in the first CAE secondary market in Spain

We are consolidating the order book with a small group of Sujetos Obligados and Sujetos Delegados. Request your invitation to access the active orders and review the published price indices.

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