Electricity self-consumption: the greenest electricity

However, there are other mechanisms to obtain energy through natural sources. more renewable, among which are the geothermal energy, widely used for hot water and heating, the small wind power, which gets energy from the force of the wind or the biomass, which uses the combustion of organic waste to generate electricity.

Whether we choose one type of electricity or another to generate self-consumption, there is a regulation that we must know, that establishes the conditions administrative, technical and economic for the different types of self-consumption. In the following report of Community of Madrid Consumer Portal We try to clarify the main doubts.

Different modes of electricity self-consumption

The legislation establishes that self-consumption facilities must belong to one of these modalities.

• Self-consumption without surplus. It is that installation that, being connected to the distribution and transmission network, has an anti-spill system, which prevents the injection of excess electrical energy into the network.
• Self-consumption with surpluses. They are the opposite installations to the previous one. They allow to inject the surplus energy of the consumption in transportation and distribution networks.

This second mode of self-consumption is in turn divided into two:

• With surpluses covered by compensation. In this mode, the energy that is not consumed is fed into the network. At the end of the billing period, the value of the surplus energy is compensated on the consumer's bill. Consumers under this modality must meet a series of requirements, which we will explain later. 
• With surpluses not covered by compensation. In this modality, the energy that is not self-consumed is fed into the network and sold, obtaining the electricity market price for it.

Both self-consumption with surpluses and without surpluses may be single, when there is only one consumer associated with the production facility or collective, if it is several associated consumers.

Requirements and technical characteristics of the facilities

In the first place, it is important to note that regardless of the self-consumption mode, consumers must have an access contract for your consumer facilities. If they do not have one, they must formalize it with the company distributor or with marketer.

However, you do not need to subscribe to a specific access and connection contract with the distribution company, it will suffice to modify the one you already have and reflect in it the self-consumption modality that has been chosen.

Remember that it is convenient that, before starting the necessary procedures for the self-consumption installation, you make sure that it can be carried out and that there is no legal or technical impediment to doing so. You can consult the Department of Urban Planning of your municipality if there is any restriction or in your Autonomous Community.

Both self-consumption facilities without surpluses and with surpluses with power less than or equal to 100 kW are exempt from carrying out the process of registration in the autonomic register of self-consumption.

Self-consumption without surplus

In the case of self-consumption facilities without surpluses, the consumer who owns the supply point Will be responsible of the installation, and of any non-compliance that could have consequences on the network. These facilities, in any of their modalities, are exempt from requesting access and connection permits, being also exempt from presenting the guarantee guarantees for the connection.

In the case of self-consumption facilities without surpluses that are collective, may benefit from a surplus compensation mechanism. In this case, the associated consumers they must agree among themselves the distribution of surpluses and communicate it to the distribution company.

Self-consumption with surpluses

Among the requirements that must be met by self-consumption facilities with surpluses eligible for compensation, are that the generating facility be of a renewable source, that the power of the production facility is equal to or less than 100 kW, have signed a single contract for consumption and for auxiliary services or that a contract of surplus compensation between producer and consumer.

For the compensation of surpluses, it happens that the energy of the self-consumption installation that is not consumed or stored by the associated consumers, is inject into the network; when consumers require more energy than is provided by the self-consumption installation, They will buy energy from the grid at the price set in their supply contract (PVPC or free market agreed with the marketer).

At the end of the billing period (which may not exceed one month), compensation is made between the cost of energy purchased from the network and the value of surplus energy fed into the network (valued at market price or at agreed between the parties depending on whether it is the PVPC or free market supply contract, respectively).

What happens if you already had a self-consumption installation before the new legislation came into force?

In the case of consumers who, before the entry into force of the new self-consumption legislation (last April), already had an installation made, they must take advantage of one of the current self-consumption modalities. They must inform the distribution company of the self-consumption mode chosen so that it can proceed to adapt the access and supply contracts.

You can consult more information about the self-consumption of electrical energy in this IDAE guide, on the processing of self-consumption.