Introduction to the challenge addressed

Producing photovoltaic energy with the installation of panels on the roofs of livestock buildings reduces operating costs, as the investment in the building can be partly balanced by the sale of electricity.  

Complementary positive effect on the environment with the improvement of the energy balance of the farm. Installations can be carried out throughout the whole territory 

 Description of the Good Practice

The hours of sunshine, the orientation and inclination of the panels, the outside temperature and the maintenance of the installations largely explain the differences in performance between installations.  

The scheme for a contract for the total resale of the electricity produced is particularly suitable for the roofs of cattle housing and fodder storage, in the beef sector. A self-consumption scheme on the farm is not suitable for beef cattle.  

It is important to check the legal aspects of the electricity resale contract.  

Development of photovoltaic installations is growing. At the end of December 2020, the surface area installed in panels on livestock farm buildings is estimated at 10 million m2. There are still many roof surfaces that can be equipped. 

This innovation is particularly recommended for new building installations, as it is more difficult to install on existing buildings (problem of stability and insertion).  

It is estimated that 40% of new buildings constructed each year could be equipped, i.e. around 1.2 million potential m2 per year in France for cattle farming.  

The constraints are the fact that the buildings on cattle farms are not exposed directly to the south, and the slope of the roofs rather at 25%, which reduces profitability by around 10%. Depending on the geographical situation, a difficulty is also the cost of connection to the electricity network.  

A “decision support tool” is available for breeders and technicians who advise them 

Experimental farms are increasingly equipped and provide references and advice 

 Impact on farm performance.

The payback time is 5 to 15 years for a moderate size installation (100 kWp) and for an invested capital of 800 to 1200 euros per installed kWe 

The increase in the maximum threshold for being eligible in France for the purchase mechanism up to 300 kWp increases the prospects for future projects.  

The net margin is estimated by Idele Institute between 34 and 39 euros per MWhé book, and possibly more. 

 Farmer comment

“With old buildings and an increasing herd size (65 suckler cows), I am forced in winter to keep outside some of my animals. Tomorrow I will be able to house all my herd in buildings in the winter. A stable covered with photovoltaic panels will be built. A second project is also underway to store fodder and equipment. In the long term, I will be able to use these buildings to fatten up part of my animals, and thus fully enhance my production. » (Young breeder, in Puy-de-Dôme)

Further information

IDELE (December 2020) document on renewable energies in livestock farms: :  https://idele.fr/?eID=cmis_download&oID=workspace://SpacesStore/6ef1ba6e-a2e7-4580-adaa-b69a6eb8909b  

Decision support tool developed by IDELE EnR2 (idele.fr) 

Article in the agricultural press (Réussir Bovins Review, August 2020) : https://www.reussir.fr/bovins-viande/photovoltaique-une-energie-simple-mettre-en-oeuvre