Production Units for Self-Consumption

The Production Unit for Self-consumption (UPAC) is an installation for the production of electricity from renewable energy sources, intended for self-consumption in the associated user installation, with the possibility of injecting surpluses into the Public Service Electricity Network (RESP).

The individual Autoconsumer produces renewable energy for self-consumption at its facilities, located in the national territory, and may store or sell electricity.

For non-domestic renewable energy self-consumers, these activities cannot constitute their main commercial or professional activity.

The holder of the Production Unit for Self-Consumption (UPAC) will have to be the same as the holder of the consumption facility, thus being able to inject the surplus energy into the grid.


Conditions for access and exercise of activity

In accordance with the legislation in force:

  1. The UPAC with installed power equal to or less than 700 W is exempt from prior control, provided that the injection of surplus into the RESP is not foreseen;
  2. A UPRAC with installed power greater than 700 W and equal to or less than 30 kW is subject to prior notification;
  3. A UPRAC with installed capacity greater than 30 kW and equal to or less than 1 MW is subject to prior registration and operating certificate;
  4. A UPAC with installed capacity greater than 1 MW is subject to the attribution of a production and operation license.


  1.  To start a self-consumption process, the customer must first register on the DGEG portal. 
  2. Once the registration is guaranteed, E-REDES will proceed with the feasibility analysis of the power to be injected into the grid.


  1. If the conditions match those requested, DGEG will grant the registration. If the conditions differ from the requested conditions, acceptance by the customer will be required for the registration.
  2. E-REDES proceeds with the creation of the Production CPE.
  3. E-REDES analyzes the meter reading and substitution or repair of the meter if necessary. 
  4. For self-consumption installations with a connection power higher than 250 Kw, the installation of an Interconnection/Homopolar Protection will be required.

After the analysis of the documentation sent, on-site monitoring of the interconnection protection tests of the production installation and respective regulation will be scheduled.


  1. Once the registration phase is concluded, the Autoconsumer will have to obtain the certification of the installation from the DGEG.
  2. E-REDES will subsequently receive a communication from DGEG, and the Self-Consumer's installation will be in operation condition, starting the reading of data inherent to the activity of the meter(s).

Availability of data/invoicing 

To obtain information about the SPC data, the Autoconsumer can register and access the Digital Counter, in the Consumption section, to consult the four curves of the load diagram (quarter hour): 

  • Consumption value registered by the meter. 

  • Injection value registered by the meter. 

  • Balance of the installation's consumption. 

  • Balance of the energy injected into the grid by the installation. 

The fourth hour balance is the difference between the consumption data in kW and the data injected into the grid in kW, in each 15 minute period. This means that everything that is produced in that 15 minute interval must be consumed in that same interval. Whatever is not consumed is injected into the grid, and another 15-minute cycle is started. 
Issues related to the sale of surplus are contracted by aggregators managed by GGS - General Systems Manager. In Portugal this activity is assured by REN. 

Self-consumption Counting Equipment 

The following are compulsory electric energy measurement points

a) Bidirectional Meter - Consumption/Production 
It corresponds to the connection point of the auto-consumer's installation to the internal grid or to the RESP, for measuring the consumption of the user installation and the surplus injected into the grid.
Distribution System Operators are responsible for the charges associated with installation and operation. If the meter is not suitable for the self-consumption regime, E-REDES will substitute/adapt it without cost to the customer. The appropriateness of the meter only occurs after the customer registers the self-consumption at DGEG's Portal.

b) Totalizer Meter 
It corresponds to the connection point to the ACU installation integrated in individual self-consumption, as long as the installed power of the ACU is higher than 4 kW, for the purpose of measuring the injection of the ACU in the user installation.
Self-consumers are responsible for the charges associated with installation, operation and replacement, as well as the modem and GSM telecommunications card.

To obtain more information about Self-consumption access the online form, available in the Contact Us area, selecting "Self-consumption and Electric Mobility".