There are more and more people interested in investing in renewable energy and disconnecting from the electricity grid, opting for self-consumption. This approach aims to produce the electricity consumed at home without depending on large electricity companies and their exorbitant prices. But as with any investment, it is important to understand the legal framework and the technical aspects involved. consumption in Spain. This includes current regulations, the equipment required and the profitability possibilities.
What do you need to have renewable energy?
To implement a self-consumption system, the main thing is to have the necessary infrastructure to generate enough renewable energy to cover your home's consumption. Whether through solar or wind mills, your goal will be to achieve independence from the electrical grid. Spain is a privileged country in terms of solar incidence, which makes solar panels an ideal option for greater energy efficiency. The costs Solar panel prices have decreased significantly in recent years, making them more affordable for most consumers.
Solar panels or small windmills
The photovoltaic solar panels are essential tools for the production of renewable energy. Advances in the technology of these panels have allowed their installation cost to decrease considerably, making the option more attractive to consumers. In Spain, hours of sun The annual cost of energy is quite high, which increases efficiency and speeds up the return on investment. In addition, the panels can be installed on roofs without taking up valuable space on the ground. As for mini-wind power, although it is also an option, it is less accessible due to the climatic conditions required and the extension of land required. However, if you live in areas where the wind is constant, mini-windmills can complement your energy consumption. 
Controller for charging, inverter and batteries
For an efficient self-consumption system, it is not enough to install panels or windmills. It is crucial to have some additional devices that help to properly manage energy. The charge regulator controls the energy that the batteries They receive electricity from generators (solar or wind) to avoid overloads and waste of resources. The inverter, on the other hand, is responsible for transforming the direct current generated by the panels into alternating current, which is what we use in our homes. Batteries are essential if you want to store that energy and ensure your supply when there is no sun or wind. Currently, one of the disadvantages of self-consumption is that battery costs are still high, and their useful life is less than that of solar panels (15 years compared to 25 for panels).
Dependence on renewable energy
If you opt for self-consumption that is completely independent of the electricity grid, it is important to keep in mind that you also become dependent on weather conditions. Solar energy depends on the sun and therefore, on rainy or cloudy days, production is reduced. In turn, the mini-wind requires winds of over 20 m/s to be efficient. Purchasing additional batteries can be a solution to ensure a constant supply on cloudy days or at night. Although this increases the investment, it is a necessary compromise to ensure supply in situations where weather conditions are not favourable. 
Self-consumption law and the tax on the sun
As for regulations, the Royal Decree 244 / 2019 The law eliminates the famous “Tax on the Sun”. This change was a relief for thousands of consumers who want to invest in clean energy and manage their energy themselves. However, if you are connected to the electricity grid, you must be aware of possible additional charges. According to the law, if you exceed the electricity consumption in accordance with your contracted power, you could be charged having to pay charges under certain parametersHowever, if your power is less than 10 kW or your installation is in the Canary Islands, Ceuta or Melilla, you will be free of paying these additional charges. On the other hand, the law differentiates between self-consumption installations isolated from the grid and those connected. If your home is completely disconnected from the electricity grid, you do not need to pay additional taxes on your production. But if you opt for a grid-connected system, you may be subject to paying a toll or charge based on the energy you pour into the grid, and if your consumption exceeds the contracted power, the excess will be penalized with a cost of up to 0,5 euros/MWh.
- Self-consumption isolated from the grid: Free of charges and exempt from any tax on the energy generated.
- Grid-connected self-consumption: Charges may apply if the contracted power is exceeded.
This law is also beneficial for those who wish to install mini-wind energy o solar thermal panels, since they are exempt from additional taxes.
Profitability of self-consumption
For those who want to enter the world of self-consumption, one of the big questions is whether the investment is profitable in the long term. According to recent studies, the amortization of the investment in solar and storage systems usually take between 8 and 10 years, with a system life of more than 20 years. As for profits, if you have a self-consumption system adjusted to the needs of your home, you could save significantly on your bill electricity, especially considering that electricity prices in Spain are among the highest in Europe. Efficient and well-sized self-consumption systems allow complete or almost complete independence from the electricity grid, considerably reducing energy costs. The savings generated will also depend on consumption and location; installing solar panels in an area with high solar radiation (such as Córdoba) is not the same as installing one with low radiation (such as Asturias). In both cases, medium and long-term profitability is assured thanks to the progressive reduction in installation and maintenance costs. 
Self-consumption of electricity: Advantages and limitations
More and more people are opting for self-consumption due to the constant increase in electricity prices. According to the CNMC Household Panel July 2023, 6,3% of households already have a self-consumption installation in Spain. This percentage is increasing due to the continuous increases in the price of electricity and the need to look for more sustainable and economical alternatives. However, it is necessary to remember that self-consumption of electricity has some limitations. Depending on where you are, the weather conditions or the intensity of the wind, you will have more or less capacity for electricity production. In places with excellent solar conditions, the savings on the bill can be noticed from the first day, while in places with fewer hours of sunshine, the payback may take a little longer. In conclusion, self-consumption is a wise decision both from an economic and environmental point of view. Although it involves a considerable initial investment, the long-term savings and the contribution to reducing our carbon footprint make this an increasingly attractive option for households in Spain. 