The history of Intergia has been as changing as the evolution of renewable energies and their perception by society.

The company, founded in 2008, started its activity in the auxiliary sector of construction and restoration of historic buildings. At that time, it was called NOVACE and provided restoration, assembly and maintenance services for companies. It was not until 2010 when, due to the economic and social situation in Spain, it took the strategic decision to join the renewable energies sector and changed its name to INTERGIA.

From the very beginning, research into off-grid energy systems was part of Intergia’s core business. As a result, the company was to some extent shielded from the volatility of the renewables sector during those early years. When, later on, legislation has finally favoured the installation of clean energy technologies, Intergia’s activity has increased exponentially year by year.

In this article we take a brief look at the renewable energy landscape in Spain, how it has evolved over the 15 years of Intergia’s existence, and where it is heading.

Before energy was renewable

Historically, hydroelectric power was for a long time the main source of electricity generation in Spain, and the only one considered to be renewable. The first hydroelectric power plants were built at the end of the 19th century, thanks to the availability of water resources on the Peninsula.

However, the share of hydropower in the electricity mix decreased significantly as other energy sources were incorporated.

The first renewables boom

The renewable energy boom did not occur until the 1980s, partly due to the increase in demand at the end of the century and the introduction of new energy technologies, mainly wind and photovoltaic.

Spain is a privileged country in terms of hours of sunshine and one of the European countries with the highest annual irradiation. This contributed to the country initially being one of the first ones in the world in research, development and use of solar energy, both photovoltaic and solar thermal, as both play a role in the renewable mix.

Thus, the development of photovoltaic technology received an initial boost during the 2000s, when the Spanish government, which had recognised the need for specific treatment for this energy alternative, published a series of Royal Decrees (in 1998, 2000, 2004 and 2007) that established specific technical and administrative conditions, as well as the stipulation of a bonus for photovoltaic kWh injected into the grid.

Based on the support that the European Union was giving to this sector, Spain drew up the Plan for the Promotion of Renewable Energies (2000-2010), which set the objective of covering 29.4% of electricity demand from renewable sources by 2010 (an objective that was more than achieved, as it reached 35%).

Thus, thanks to favourable legislation, a large investment was made in research, development and deployment of photovoltaics, with high productivity. In 2008 Spain was one of the countries with the highest installed photovoltaic capacity in the world. At the end of the same year, the installation of photovoltaic capacity was regulated by Royal Decree 1578/2008 on the remuneration of photovoltaic solar energy, which established variable bonuses depending on the location of the installation (ground or rooftop), and was also subject to a maximum quota of annual installed capacity from 2009, which would be adapted year by year depending on market performance.

However, during these years the market was very volatile. Specifically in Spain, the so-called “brick boom” in the construction sector led to the speculative bubble of rising prices that eventually burst and led to the Spanish real estate crisis of 2008.

In terms of energy, the legislation that followed put the brakes on the deployment of this technology, slowing down the construction of new photovoltaic plants in the country, compared to the evolution of renewables that has continued to a greater or lesser extent in all EU Member States since 2004.

Difficulties and obstacles: the “sun tax”

The setback in the development of renewable energies in Spain as an alternative for the decarbonisation of the economy culminated with the so-called “sun tax” (in reality, “transitional charge for self-consumed energy”), approved in Royal Decree 900/2015 of 9 October, which regulated the administrative, technical and economic conditions for self-consumption installations. This tax consisted of a specific support toll applied to energy generated by photovoltaic installations, i.e. the consumer had to pay the corresponding taxes for the electricity produced by their self-consumption system, even if the energy generated was not injected into the grid. This tax was justified as necessary to guarantee the sustainability of the electricity grid, setting a toll for the maintenance of the electricity grid for users of renewable energies.

It must be said that, despite its controversy, in few cases was this decree enforced, as isolated installations, self-consumption installations of less than 10 kW at low voltage (the majority of homes with self-consumption) and those located in the Canary Islands, Ceuta and Melilla were exempt from paying the toll.

However, the “sun tax” had very negative deterrent effects, which slowed down Spain’s self-consumption targets. One of the reasons for this was the complexity of legalising a PV installation and not being able to receive any compensation for surplus energy.

Repeal of the “sun tax” and a new boost for self-consumption

On the 5th October 2018, Royal Decree-Law 15/2018 repealed the controversial “sun tax”, thus unblocking the obstacles to self-consumption and greatly boosting the deployment of photovoltaic technology in Spain. Since then, a series of reforms have been announced and implemented to promote the use of solar energy.

Royal Decree 244/2019 significantly simplified the administrative procedures for applying for self-consumption installations. Some of the most important reforms to promote self-consumption have been:

  • Elimination of the generation meter in photovoltaic installations without inyection to the grid.

  • Installations with a capacity of less than 10 kW and stand-alone installations are exempted from applying for permits from the electricity company.

  • Approval of the compensation and sale of self-consumption energy surpluses.

  • Approval of collective self-consumption, which has opened up the possibility of several users sharing the same self-consumption installation.

Meanwhile, worldwide, the costs of photovoltaic generation have fallen dramatically as increasingly efficient technology has been developed, which has helped to boost photovoltaic self-consumption. In addition, nowadays, the Autonomous Communities offer subsidies and incentives to invest in photovoltaic systems, and the European Union is providing more and more financial aid (such as the Next Generation EU Funds) to promote clean energy projects that contribute to the decarbonisation of the economy and to meeting the objectives of the European Green Deal. For these reasons, photovoltaic self-consumption installed power has been doubling every year since 2015, with forecasts clearly on the rise.


The installed capacity of photovoltaic self-consumption reached 3,233 MW in 2021 and in 2022 around 2,400 MW more were installed (Source: Newtral.es graph, based on data from APPA Renovables).

Renewables in Spain today

According to data from Red Eléctrica (REE), Spain was the second European country that generated the most energy from wind and solar technologies in 2021. Renewable generation accounted for 46.7% of the energy mix, with wind being the leading technology in the generation mix with more than 23%. Installed solar PV power capacity reached 15,048 MW in 2021. In 2022, solar PV installed more capacity and had more production than ever before, and PV is expected to be the fourth largest technology in the generation mix for the first time, accounting for 10% of total electricity generation in Spain.


Installed photovoltaic power. Stagnation can be seen from 2015 to 2018 due to the obstacles caused by the sun tax. (Source: Red Eléctrica de España)

This upward trend in renewable energy deployment answers to environmental concerns and indicates that Spain is on track to meet the targets set by the National Energy and Climate Plan 2021-2030 (PNIEC). This Plan has set a target for Spain to achieve 74% renewable generation by 2030 with a view to being 100% renewable by 2050.

What will happen from now on?

The ecological transition envisages the electrification of the economy for its decarbonisation. This includes several aspects: in addition to the massive deployment of renewable generation technologies, energy storage technologies, the adoption of electric mobility, the abandonment of fossil fuels in industrial processes, the use of green hydrogen as a clean energy vector…

The latest regulations already reflect this desire to transition to a more sustainable model. Distributed generation is increasingly being promoted and models such as collective self-consumption and local energy communities are being encouraged.

Thanks to INTERGIA’s track record and the experience acquired over the last 15 years, we have become experts in the energy sector and in the search for solutions in the field of energy efficiency, clean energy and sustainability.

We specialise in:

  • photovoltaic generation, both grid-connected and off-grid;
  • electric mobility solutions for vehicle charging;
  • green hydrogen generation;
  • and climate change mitigation actions.

In addition, we have a strong focus on energy and sustainability research.

If you have any questions, please do not hesitate to contact us.