Hybridisation of renewable energy: There are only advantages

There is no doubt that the future lies in addressing climate change and this is why renewable energy sources are one of the most reliable options. The problem with these alternative energies may be their high cost, the difficulty of offering a constant, stable production because they depend on natural elements and because of the impact caused by the creation of new production plants. With this in mind, hybridisation may be the best solution.

What does the hybridisation of renewable energies consist of?

Renewable energy hybridisation is an energy generation process that uses two or more different energy sources taking advantage of the same capacity for evacuation. It should be borne in mind that one of the greatest impediments to the growth of renewable energy is the connection capacity, and the hybridisation of existing installations is one of the available solutions.

One of the principles on which hybridisation is based is complementarity: To be more efficient, the aim is for each of the energy sources to work when the other is inactive and this enables a constant flow to be guaranteed. In this regard, one of the most common examples is to combine photovoltaic solar energy, which works during the day, with wind energy to be exploited at night.

There are currently two types of hybridisation allowed by the regulations:

• New plants built for hybrid development.
• The hybridisation of new generation modules from existing installations, provided that they are not dismantled.

Advantages of renewable hybridisations

We know that hybridisation has multiple advantages for both production companies, institutions and society in general. To start with, by sharing evacuation infrastructure, such as power lines and substations, the environmental and landscape impact is much lower than if a new plant has to be built.

Another advantage of the hybridisation of renewable energies is that it enables production to be increased in plants that, due to their construction date, no longer yield to their full potential. For example, this is the case of many wind farms which can be subjected to repowering as well as hybridisation with other energy sources. The fact is, for the Ministry of Ecological Transition and the Demographic Challenge, hybridisation is a strategic solution with regard to its commitment to renewable energies:

"The technological refurbishment of existing renewable installations, by changing the machinery and/or repowering the installation which is reaching the end of its useful life and if this is not done it is foreseeable that there will be a reduction in the installed power of renewable origin. At the environmental level, changing the machinery, repowering and even hybridisation may have a lower impact by concentrating renewable generation in a specific environment, reducing the total number of machines and thus the project's footprint, and reducing the need for new network cables".

This possibility of updating existing plants also enables the reduction of management and logistics costs while increasing jobs and local investment. It also reduces the need for public investment, as there is no longer a need for so many grid expansions to increase the penetration of renewable energies into the system.

Most common types of hybridisation

Hybridisation systems are usually classified depending on two criteria:

• The technologies to be combined: Wind, photovoltaic, hydroelectric, thermal... In Spain, the most common hybridisation involves a combination of solar energy and wind energy, because due to the climate and the peculiarities of our geography, they are the renewable energy sources that produce the most in Spain.
• Whether or not they have energy storage systems: Plants that have storage are more flexible because they can hybridise a number of technologies. By accumulating the energy that cannot be fed into the grid when generation by both sources is at its highest, a better subsequent supply is guaranteed.
  

Examples of hybridisation in Spain

Spain has traditionally been a global benchmark with regard to renewable energies, both in terms of installed capacity and technology. This, together with political and social commitment, can still be seen today in the adoption of technological improvements such as hybridisation.

Because of the characteristics of the power plants in Spain and their construction date, there is plenty of room for optimisation through hybridisation. For example, according to Government estimates, based on a study conducted in 2021, of the 137 MW of wind power with installations more than 10 years old in the Canary Islands, this could be increased to up to 340 MW of power through repowering and hybridisation projects. This represents an increase of 148% compared to the initial power.

Endesa has a number of examples of successful hybridisation that clearly reflect our commitment to efficiency and sustainability. Some of these, completed in 2022, include the following:

• Fair Transition Tender for Pego (Portugal): A hybrid renewable energy project combining 365 MWp of photovoltaic solar energy and 264 MW of wind energy. It will also have the largest battery storage in Europe: 168 MW.
•  Floating Solar Panel Tender (Portugal): For the installation of 43 MWp of floating solar power, 48 MW of wind energy and 49MW of battery storage at the Alto do Rabagão reservoir.
  
• Fair Transition Tender for Andorra (Teruel): This will enable the development and construction of 1,800 MW of new hybrid renewable capacity distributed amongst seven solar plants, seven wind plants, two battery storage plants and an electrolyser for the generation of green hydrogen.