Collective purchases 50 + 1: For every 50 PV purchased, 1 is given to a non-profit entity
Faced with the need for citizens to take a more active role in the production and management of more sustainable, efficient and distributed energy, the Som Energía cooperative makes use of the collective purchasing model (CPM) to implement a set of self-consumption PV installations for members of the cooperative and with a house with its own roof.
This CPM allows to obtain an adjusted market price when buying a large number of self-consumption installations at the same time. In adittion, it facilitates the processing, ensures the execution by a solvent installation company and the advice of Som Energía in all phases of the process from the selection of the installation company, through the registration of interested members as part of the purchase collective, personalised studies in the homes, execution of installations and monitoring and advice to adapt energy uses once the member is already generating their own energy.
The collective purchase is made by zones that include 3 or 4 provinces. In the case of Andalusia, the Local Group of Seville and Los Alcores (GL) manages “SolSurAutoproduction” that covers Huelva, Seville, Cadiz and Córdoba.
For the choice of the installation company, a competition has been carried out, with the criteria and the conditions established by the GL.
For each CPM, a self-consumption PV installation is donated to a non-profit company. In this case, it has been for the AFAR National Association.

Resources needed

To manage all active collective purchases, the development of competitions, coordination with companies and attention to registered people, it represents a total of 2.5 people hired full time. It is also very important to highlight the work of the volunteers.

Evidence of success

Total registrations: 62
• Total discarded projects: 11
• Installations in operation: 48 and Ongoing projects: 3
Approximate installed power: 145 kW
Approximate generation: 210 MWh / year

Difficulties encountered

This CPM not only reduces costs, but also makes it easier to manage the administrative and legal procedures for those who want to self-produce their own electricity.

Potential for learning or transfer

The results were very positive so it was decided to promote a new edition in Western Andalusia and replicate the initiative in Eastern Andalusia with a new collective purchase.

The collective purchases in Som Energia are already a consolidated action of the cooperative with already some 32 collective purchases promoted and some 1,500 installations underway spread throughout the Spanish state that represent about 6 GWh / year of generation.

This experience shows that the most effective way to promote domestic solar installations is to bring together many interested people at the same time, in order to achieve more competitive prices and simplify installation tasks. The intention is to continue replicating the initiative in other areas of the territory. In fact, there are about twenty more purchases in progress and four in the gestation phase.

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Main institution
Som Energia
Andalucía, Spain (España)
Start Date
January 2020
End Date


Ruth Borrego Andrade Please login to contact the author.