In Spain, roughly ten million rooftops are technically suitable for turning into small, sun-powered energy sites. A leading Catalan utility highlights that if every viable roof hosted five kilowatts of solar capacity, the national electricity output could rise by about 40 percent from the current level of around 124,000 megawatts and could even meet domestic demand. This optimistic projection stems from a study on the potential and current status of distributed generation across the country.
A key distinction emerges between self-consumption, where electricity is produced for personal use, and distributed generation, which involves sharing power with neighbors by selling any surplus back to the grid. In recent years, driven by higher energy costs and the pandemic, self-consumption has surged across Spain, surpassing five gigawatts installed. Most installations, however, are geared toward personal use without a surplus feed into the grid.
The focus now shifts to expanding the second model, where energy is produced for nearby households and any excess is sold to the grid. This approach holds the promise of up to 50 gigawatts and is viewed as the quickest and most efficient route to achieving a target of generating 81 percent of electricity from green sources by 2030, up from the current share of about 50 percent. Solar installations typically require less construction time and fewer permits than large wind and solar farms. Locally consumed energy also means fewer transmission losses, further boosting efficiency.
Adding battery storage could smooth operation by letting a network of batteries function as a virtual production plant, storing energy during the day and releasing it at night. More importantly, this strategy could lower household bills.
The starting premise is straightforward: a typical family spends around 84,400 euros on energy bills over twenty years, covering electricity, gas, and car fuel. Installing rooftop panels could trim that expenditure by about 30 percent, bringing the total to roughly 61,400 euros. If a household also owns an electric car instead of a fossil-fuel vehicle, savings could climb to about 70 percent (roughly 27,800 euros). With a heat pump added and full electrification of consumption, the bill could approach zero euros.
In the broader energy plan, Spain aims to install about 19 gigawatts of self-consumption capacity by 2030, a fraction of the broader potential for distributed generation. Today, around 500,000 such installations exist, representing roughly 5 percent of the market, leaving Spain behind peers in Europe and beyond. A coordinated push toward collective self-consumption, energy communities, and smoother connections for distributed generation could help close the gap.
Experts note that Spain could lead Europe in the energy transition thanks to abundant sunshine, yet solar penetration remains modest relative to the number of viable rooftops. A growing roster of rooftops has transformed into energy producers, with hundreds of thousands of electricity contracts already in place and millions more potential just waiting to be tapped.
The regulatory hurdle is not only about consumer choice. The push calls for faster momentum from regulators to expand collective energy schemes, empower self-consumption managers, and promote distributed-storage installations that can be traded on secondary markets when the system needs it. Aligning distribution-company targets with smoother connections for distributed generation and exploring incentives such as VAT relief or subsidies could further accelerate adoption and lower barriers for homeowners and communities alike.