Tens of thousands of homes and businesses in Spain relied on solar self-consumption. to gain energy independence and reduce their electricity bills. However, power outages have revealed that Most facilities are not prepared to operate autonomously if an interruption occurs, unless they have certain advanced components.
In recent years, solar self-consumption has grown steadily., driven by the elimination of regulatory barriers and European aid. Today, there are almost half a million homes and more than 75.000 businesses in Spain with photovoltaic systems for self-consumption, mainly located on rooftops and terraces. However, in 2024, the pace of new installations will have dropped significantly compared to previous years, reflecting the new reality of the sector.
One of the recurring concerns of self-consumers is to know why, even though they have solar panels and even batteries, they are left without electricity during a blackout. The answer lies in the technical and regulatory configuration Of most systems: Only installations with island-compatible hybrid inverters and dedicated backup systems can continue to operate on solar and battery power if the grid fails.
The Spanish market is thus facing a change of scenario.: While more than 2022 self-consumption units were installed in 240.000, the figure dropped to 2023 in 127.000, and fell even further in 2024, to fewer than 80.000. The reasons for this are varied, from the disappearance of the "pull effect" due to high electricity prices or subsidies, to uncertainty over regulations and negative prices in the electricity market.
Why does my self-consumption system shut down if there is a power outage?
One of the main misunderstandings among self-consumption users It is to assume that having solar panels is enough to guarantee supply in the event of a blackout.
Most grid-connected self-consumption systems They automatically disconnect their production when they detect a loss of voltage in the public grid. This action is required by law (anti-islanding protection) to protect grid technicians during potential maintenance work.
For a home or business to be able to take advantage of solar energy during a blackout, it needs:
- Hybrid inverter or inverter with backup function capable of operating in island mode
- A battery bank adequately sized
- Switching system (bypass) that isolates the installation from the network
- Management system that prioritizes critical consumption (lighting, refrigerator, Wi-Fi, essential appliances, etc.)
At present, The vast majority of the nearly 500.000 self-consumption installations in Spain do not meet these requirements., hence the loss of the grid means being left without supply even if solar panels and batteries are installed.
Types of self-consumption installations and their behavior during blackouts
There are three major configurations of photovoltaic self-consumption from the point of view of backup capacity:
- Grid-connected installations without batteries: These are the most common (around 85% domestic). They provide instant solar energy in parallel to the grid, but In case of a power outage they automatically disconnectNighttime or bad weather power is always covered by the grid.
- Grid-connected installations with batteries (without island mode): They allow solar energy to be stored for use when there is no production, but They also require the presence of a network to functionThey also disconnect during blackouts unless they incorporate special backup systems.
- Hybrid installations with backup (island mode or backup): These facilities can continue supplying solar and battery power to the home or business during a power outage, provided they have the appropriate inverters and automation systems. They are a minority in Spain but predominate in countries like Germany.
Spanish regulations (RD 244/2019, UNE-EN 50438:2014, REBT…) It regulates the technical and safety requirements that these systems must meet, differentiating between conventional installations and those enabled to operate autonomously.
The importance of batteries and the advancement of storage
Solar batteries have become a strategic component to maximize self-consumption and move closer to energy self-sufficiency. In Spain, 26% of new residential installations already incorporate them, although most still do not allow off-grid standalone operation.
According to data from the Spanish Photovoltaic Union (UNEF), In 2024, 327 MWh of batteries were installed, down 34% from the previous year, reflecting the slowdown in the sector. However, the importance of batteries is growing in the industrial and commercial sectors, where continuity of supply is more critical.
Storage allows:
- Extend the use of solar energy for more hours a day
- Reduce grid dependence during times of high prices or polluting generation
- Improve facility planning and efficiency
- Ensure emergency supply if the facility is prepared for it
While in countries like Germany and Italy, more than 70% of residential installations include batteries, in Spain this percentage ranges from 10% to 26% depending on the source, with an upward trend as prices fall and awareness increases.
Regulations, administrative challenges and the future of self-consumption
El Photovoltaic self-consumption in Spain is regulated by a legal framework that has evolved significantly since 2019, favoring the expansion of residential and industrial facilities. The main regulations involved are the Royal Decree 244 / 2019, the technical directive UNE-EN 50438:2014 and the Low Voltage Electrotechnical Regulations, among others.
In the last months, The sector demands new measures to continue growing, especially after the slowdown of the last two years:
- Simplification of administrative procedures and digitalization of processes
- Review of the fixed term of the electricity rate to encourage savings
- Legal recognition of self-consumption without license plates (only storage and smart management)
- Extension of the power range with simplified processing up to 500 kW
- Creation of the figure of the collective self-consumption manager to streamline shared projects
There is also a demand for greater homogenization of procedures between Autonomous Communities and distributors, and fiscal policies that include tax reductions on materials and components to facilitate access to technology.
Industrial and collective self-consumption: advantages and obstacles
El Industrial self-consumption leads the installed capacity in Spain, representing nearly 74% of the total compared to 26% for residential use. Companies find solar energy a way to increase their competitiveness, protect themselves from volatile electricity prices, and take firm steps toward sustainability.
However, the Collective self-consumption (neighborhood communities, industrial estates, etc.) is progressing slowly due to the complexity of procedures, the lack of concrete incentives and the poor administrative coordination.
Among the most notable obstacles are:
- Difficulty coordinating distribution agreements and additional counters
- Inequality in the application of regulations according to the Autonomous Community
- Poor preparation of urban networks to manage collective energy flows
- General lack of awareness about the advantages and options of shared self-consumption
The future prospects are accelerate the digitalization and standardization of procedures, promote access to financing and continue reducing the costs of key equipment such as hybrid inverters and batteries.
Despite the contraction experienced in the last two years, photovoltaic self-consumption It remains one of the most accessible and competitive technologies for moving towards decarbonization. and energy self-sufficiency. Smart energy storage and management will be key factors in the path toward a more sustainable and decentralized energy model in Spain.
