Get paid for saving energy: how to earn money by improving energy efficiency, step by step

Put simply, 1 ESC is equivalent to 1 kWh of energy saved per year as a result of a specific improvement. For example, if you replace your old fridge with one that uses 300 kWh less per year, you could obtain 300 ESCs. However, the process, as well as the assessment and conversion of these ESCs into money, must follow the steps and conditions set out in the regulations:

1. Decide to make an improvement that qualifies for certification

First, you'll need to check whether the energy improvement you plan to make is covered by the regulations. The Ministry for the Ecological Transition and the Demographic Challenge (MITECO) has a catalogue of standardised measures that is updated regularly, so it's advisable to check it before going ahead with the purchase or renovation you have in mind.

2. Calculate the corresponding energy savings

Each measure results in energy savings, which can be calculated using the formulas and reference values included in its catalogue fact sheet. Although this method helps eliminate subjectivity from the calculation, the formulas can in fact be somewhat complex for most of us. If that's the case, we recommend seeking help from a specialist in this field.

3. Gather all the necessary documentation

The Ministry's catalogue fact sheets also specify which documents need to be submitted to convert your energy savings into ESCs, depending on the measure you decide to carry out. Bear in mind that you may need documents relating to the items or appliances you are replacing, not just the new ones. This means you may sometimes need to rummage through drawers and check that you still have everything you'll be asked to provide.

4. Transfer ownership of your energy savings

This is one of the distinctive features of the ESC system: you own the savings you generate, but you are not allowed to ‘sell’ them. The parties responsible for converting them into money and, in fact, for handling the rest of the process are the obligated parties and delegated parties:

• Obligated parties are energy companies. As they are legally required to achieve a certain amount of energy savings each year, they can do so through ESCs they generate themselves or by acquiring savings from other companies and individuals. Endesa, for example, is an obligated party.
• Delegated parties are companies that specialise in obtaining ESCs for obligated parties. They act as intermediaries between energy companies and consumers.

What does this mean? At this stage, you'll need to choose one of them and agree to transfer your savings to them in exchange for money, under an agreement known as an ESC Agreement.

5. The savings are verified and the ESCs are issued

Once you have transferred ownership of your savings, the obligated or delegated party will take care of managing them. First, they'll submit the application to an accredited body for verification and then arrange for the ESC to be issued by the relevant autonomous community.

6. You receive the agreed compensation

If the procedures outlined in the previous step are completed successfully, the company you signed the ESC Agreement with will pay you the agreed amount, in accordance with the terms you agreed at the time.

What home improvements can qualify for an Energy Saving Certificate?

In general, anything that can help you save energy at home can also help you obtain an ESC. And although the quickest way to find out whether your improvement is covered is to check the Residential Sector Fact Sheets Catalogue, the scheme is also open to more complex projects, provided that their impact on savings can be verified.

As a general guide, these are some of the most common measures carried out in homes and whether they can qualify for an ESC provided they meet the requirements:

* Subject to the technical and documentary requirements set out in the applicable fact sheet.

How much money can you receive for your ESCs?

In practice, the value of an ESC is determined by the market at any given time. Companies that are obligated parties will be willing to pay more or less for each ESC depending on how urgently they need to cover the savings required by law and on their capacity to do so. And that is the first factor that determines how much money you can receive.

On the other hand, each delegated party operates in this market and manages their own forecasts, capabilities and scenarios to offer a price per ESC, both to energy companies and to you, as the owner of the savings.

This means that the price you receive for each kWh you save, which is equivalent to one ESC, cannot be compared with the price of each kWh you use at home and which is listed on your bill, as these are entirely different concepts and markets.

For this reason, the financial compensation for your savings is the amount you agree when you sign your ESC Agreement with the company you choose, whether it is an obligated party or a delegated party.

What determines how much you can earn from an energy improvement?

1. The energy savings generated: the more kilowatt-hours you save, the more ESCs you earn and, consequently, the more money you can receive for your improvement.
2. The type of measure: each improvement you make results in a different amount of energy savings, which is why each fact sheet in the ESC scheme sets out the correct way to calculate them.
3. The characteristics of your home: depending on the project, particularly when structural improvements are involved, the impact on savings varies according to the size of the home, the climate zone, current energy consumption, the consumption after the improvement and other criteria that make it difficult to name a ‘fixed’ number of ESCs per home.
4. The price agreed in your ESC Agreement: ultimately, the financial value of the ESCs you qualify for will be the amount you agree when you transfer ownership of the savings. This is particularly important to consider if you expect to use this scheme to cover part of the cost of an expensive renovation.

What documents do you need to provide to demonstrate your energy savings?

Again, every case is different, as set out in the relevant fact sheet under the ESC scheme. However, broadly speaking, the documents you are most likely to be asked to provide to verify your savings are:

• Invoices for the energy-efficiency renovation and/or equipment purchased.
• Proof of any payments made.
• Documentation relating to the old equipment, where applicable.
• Energy performance certificates and installation documentation.
• Before-and-after photographs, if required by the relevant fact sheet.
• Any required declarations of responsibility.
• Information about other financial support or grants, where applicable.

Are Energy Saving Certificates and Energy Performance Certificates the same thing?

In short, no. Even though their names are similar, and both terms relate to the efficient use of energy in the home, ESCs and EPCs refer to different things:

• An Energy Saving Certificate (ESC) is a way of earning income from certain energy-saving measures you carry out.
• An Energy Performance Certificate (EPC) is a document that rates the energy performance of a home.

These are the four main differences between them:

Can ESCs be combined with grants for home renovations?

Energy Saving Certificates are not grants and, in most cases, they are compatible with grants intended to fund energy-efficiency renovations to homes.

However, there are two conditions you should bear in mind:

1. ESCs cannot be combined with grants funded by the National Energy Efficiency Fund (FNEE).
2. The combined amount received from ESCs and any potential grant cannot exceed 100% of the cost of the measure carried out.

Therefore, before you decide to combine a grant with the ESC scheme, it is advisable to check a few details about the grant you intend to apply for:

• Who is funding it and whether the money comes from FNEE funds.
• What the applicable terms and conditions say about this.
• How much you will receive from the grant and how much from the ESCs.
• What documentation you will need to provide.

How to obtain ESCs for energy improvements already carried out

The ESC scheme covers renovations and appliance replacements carried out since 26 January 2023. This means that you can apply for ESCs for measures you carried out from that date onwards, not just for those you are planning to undertake.

To do so, you will need to:

• Have kept all the relevant documentation.
• Check whether the measures are covered by the corresponding fact sheets.
• Make sure you meet the requirements.
• Check that there are no specific time restrictions.

FAQs about Energy Saving Certificates

What is an Energy Saving Certificate?

It is a way of certifying each kWh of energy saved as a result of a renovation or appliance replacement you have carried out at home. Each certificate can be converted into financial compensation for you.

How much is each Energy Saving Certificate worth?

ESCs do not have a set price. Their value depends on the agreement you reach with the companies authorised to manage them under the ESC Agreement.

What is an obligated party under the ESC scheme?

It is an energy company that is required to achieve a certain amount of energy savings each year and report them to the authorities. To do so, it is one of the authorised parties that can agree to pay financial compensation for the energy savings you generate at home.

What is a delegated party under the ESC scheme?

It is an intermediary company authorised to acquire the savings you generate at home in exchange for financial compensation and transfer them to obligated parties.

How much can I earn from carrying out an energy-efficiency renovation at home?

The amount you can earn through ESCs depends on the scale of the renovation, the conversion formulas established under the scheme and the price per certificate you agree with the authorised company under the ESC Agreement.

Can an individual obtain ESCs and benefit financially?

As an individual, you cannot obtain ESCs directly. However, you can benefit from them. When you carry out a measure in your home, you become the owner of the savings it generates. You can then negotiate the transfer of those savings in exchange for money with authorised companies, which will handle the process and convert them into ESCs.

Can replacing windows qualify for an ESC?

Generally, yes, if the new windows improve the home's energy savings. The ESC fact sheets catalogue sets out the requirements you need to meet to obtain certificates for replacing windows and carrying out similar improvements.

Can installing an air source heat pump qualify for an ESC?

Yes, it can. Replacing certain combustion-based systems with more energy-efficient alternatives, such as an air source heat pump, can qualify for an ESC provided the applicable fact sheets for the residential sector are met.

Can replacing a fridge, washing machine or dishwasher qualify for an ESC?

This can qualify for an ESC, depending on the characteristics of the new and old appliances. The scheme's fact sheets catalogue covers certain appliances and energy-efficiency levels, along with the requirements they must meet to be validated.

Are ESCs compatible with grants?

Yes, with two exceptions: grants funded by the National Energy Efficiency Fund, or grants that include a specific condition regarding compatibility. In addition, the combined amount received from ESCs and grants cannot exceed 100% of the investment made.

Can I obtain ESCs for a renovation I carried out in 2023?

Yes. You can obtain ESCs for measures carried out from 26 January 2023 onwards, provided that the measure is covered by the ESC scheme's fact sheets and meets the requirements.

Are ESCs and Energy Performance Certificates the same thing?

No. An Energy Saving Certificate (ESC) certifies each kWh of energy saved as a result of a specific measure. On the other hand, an Energy Performance Certificate certifies the energy performance of a property.

* Article last updated on: 1 September 2026.