D1 to D5 documentation for CAE files: complete guide with examples

The five documents of a CAE file

Every Certificados de Ahorro Energetico (CAE) file must include five types of documents, designated D1 to D5, which justify the reality of the energy efficiency action and the associated saving calculations. This documentation is what the ENAC verifier reviews before the MITECO issues the certificates.

The quality and completeness of these documents is the determining factor for a file to pass verification without observations. A well-documented file can be verified in 2 to 4 weeks. An incomplete one can take months or be rejected.

D1 - Baseline situation of the existing equipment

The D1 document describes the equipment or system that will be replaced or improved. It is the baseline against which the energy saving is measured.

What the D1 must include:

• Identification of the existing equipment: brand, model, serial number, year of installation
• Rated power of the equipment (kW, W or according to the datasheet's unit)
• Efficiency or performance of the existing equipment (COP, EER, rated efficiency, luminous efficacy)
• Number of units or affected area
• Exact location of the equipment in the installation

Accepted sources for the D1:

• Equipment nameplate (legible photograph)
• Original manufacturer datasheet
• Technical inventory of the installation
• Prior energy audit

Common mistake:

Declaring the baseline situation without documentary support. The verifier does not accept "estimated" values for existing equipment without a verifiable source.

D2 - Technical documentation of the new equipment

The D2 document describes the equipment or system installed to generate the energy saving.

What the D2 must include:

• Complete technical datasheet of the new equipment (from the manufacturer)
• Performance specifications: power, efficiency, SCOP, SEER, luminous efficacy, energy class
• Conformity certifications (CE marking, Eurovent, EnergyStar certification where applicable)
• Number of units installed
• Guarantee of compliance with the datasheet's regulatory thresholds (e.g. LED >= 130 lm/W)

Common mistake:

Attaching a commercial datasheet that does not include the technical data needed for the calculation. For example, an LED luminaire datasheet that shows the lumens but not the luminous efficacy in lm/W. The verifier needs the exact value that is entered into the formula.

D3 - Invoice or contract for the action

The D3 document is the economic proof that the action has actually been carried out.

What the D3 must include:

• Invoice or contract with date, NIF of the supplier and of the client
• Description of the action (type of equipment, quantity, reference)
• Total amount of the action (VAT included or itemised)
• If it is a contract, the scope of the service and the execution dates

Common mistake:

Submitting a generic invoice that does not allow the action to be identified ("electrical work" without detailing the replacement of luminaires, for example).

D4 - Before and after photographic report

The D4 document provides the visual evidence of the replacement or improvement carried out.

What the D4 must include:

• Photographs of the old equipment before the replacement (in situ)
• Photographs of the new equipment after installation (same location)
• Nameplate visible in the photos (whenever possible)
• Date and time in the photo metadata (or visible annotation)
• Recognisable location of the equipment (so that the verifier can confirm it is the same site)

Common mistake:

Low-quality photos that do not allow the nameplate to be read, or "after" photos with no visual correspondence to the "before" photos (the same premises cannot be recognised).

D5 - Justifying calculation of the energy saving

The D5 document is the technical heart of the file. It contains the detailed calculation of the energy saving in accordance with the formula of the applicable standardised datasheet.

What the D5 must include:

• Identification of the standardised datasheet applied (code, title, regulatory reference)
• All calculation parameters with their values and units
• Source of each parameter (D1, D2 or default regulatory value)
• Step-by-step application of the official formula
• Annual saving result in kWh/year and MWh/year
• Calculation of the total CAE (annual saving of one year)
• Regulatory reference (Orden TED/845/2023)

Common mistake:

Preparing the D5 in an Excel spreadsheet without traceability, with formula errors or without reference to the regulation. The verifier needs to be able to follow the calculation step by step and check that the formula applied is the correct one.

CertificAhorro automatically generates the D5 document with all the parameters, formulas and regulatory references, ensuring the consistency and traceability required by the ENAC verifier.

Verification checklist before sending the file

Before sending the file to the ENAC verifier, it is recommended to check the following points:

1. The five documents D1 to D5 are present and complete
2. The D5 parameters match the values documented in D1 and D2
3. The datasheet's regulatory thresholds are met (automatic verification in CertificAhorro)
4. The D4 photos are clear, dated and allow the equipment to be identified
5. The D3 invoice describes the action with sufficient precision
6. There are no inconsistencies between the five documents