Empreinte Photovoltaïque Zéro©, has the public interest as its main pillar, as this is the only way to achieve the consensual and globally sustainable development of the renewable energy sectors needed to protect the environment.
AgriVitiVoltaïque EPZ© is a way of combining, for the good of all, an industrial activity of general interest with another sector of general interest neglected by all: agriculture. Farmers must be guaranteed to stay on their land over the long term, and must be able to return safely to their families when their industrial operations come to an end.

To achieve this, two factors need to be taken into account:

  • During the operation of AgriVitiVoltaic EPZ © farms, farmers must be able to continue farming on their land.
  • The dismantling of photovoltaic installations and the return of unused land at the end of their industrial life.

We have established the following rules, which are detailed over 30 pages in the emphyteutic leases we sign in Spain and which I am pleased to summarize below:

1-Benefits for the farmer.

  • The properties selected must be between 7 and 60 hectares in size, and preferably located in a landscape context contaminated by roads, freeways, railroads, high-voltage lines, extra-high-voltage lines, etc.
  • Annual rent of 3,400 euros per hectare paid to the landowner. Must prove that he has owned them for more than five years, to avoid speculation by property dealers who might be tempted to buy from farmers in difficulty and then rent them out at a high price, angering the farmers who would do so. A feeling of speculative use and rejection of the photovoltaic sector.
  • The owner benefiting from this lease must automatically waive all agricultural subsidies (including CAP) in favor of the cooperative winery and/or chamber of agriculture closest to the AgriVitiVoltaic EPZ©. project for the duration of the long lease.
  • Les propriétaires qui nous ont loué leurs terres ont la possibilité de poursuivre gratuitement leur activité agricole entre les rangées de panneaux distantes de 8,80 mètres. Dans le cas contraire, de jeunes agriculteurs peuvent être sélectionnés par la coopérative et/ou la chambre d’agriculture, la municipalité ou tout autre organisme public pour travailler dans la partie agricole des projets de la AgriVitiVoltaïque EPZ©. La nouvelle activité agricole est divisée en plusieurs unités productives qui permettent de compenser le manque de rayonnement et la réduction des surfaces:
    • Fences prevent damage caused by wild boar and other predators.
    • Additional agricultural production in hedgerows, such as berries.
    • Additional agricultural production with fruit trees on the perimeter.
    • Beekeeping if possible at the end of the panel rows.
    • Agricultural production in the middle of the panels, choosing the agricultural / viticultural / livestock option.
      • Example of additional agricultural production:

2-Environmental benefits :

  • Uncultivated areas must be managed in accordance with the Plan SGIAR 4per1000 program https://www.4p1000.org/, allowing the soil to regenerate.
  • Agricultural activities should only be carried out under the “BIO” label http://www.ccpae.org
  • The land normally used for photovoltaic power plants is compacted and therefore condemned to cease production.
  • The biodiversity created in the AgriVitiVoltaic EPZ © parks enables the growth of local agriculture (KM0) and the conservation of endangered species.
  • Complete landscape integration.

Study of earth temperature drops

  • Shadow and radiation study of the EPZ program.
  1. Introduction

In 2009, Guy de Maillé developed the Empreinte Photovoltaïque Zero© system, which makes it possible to combine a photovoltaic installation with farming-livestock activity on the same plot of land, using the space between the rows of panels and the perimeter zone, as well as any other areas not covered by panels (under power lines, etc.).

To assess the interest of either activity, it is necessary to know the level of shading generated by the ground-mounted solar panels.

  • Procedure

The space beneath the panels was divided into longitudinal rows 0.5 m wide. As the solar panels and zones are oriented north-south, the areas on either side will have received equal radiation throughout the day due to the symmetry. The result is a central zone and 9 other zones per side.

The average shading received per month was simulated by the shading coefficient (or percentage) per zone and per month. Shading coefficients are applied to a particular location, knowing its historical solar radiation, and the solar radiation received is obtained.

A simulation has been carried out for the specific case of Igualada, as this is an average area of Catalonia, and these coefficients are valid for any place of similar latitude, which for us will be valid for the whole of Catalonia.

  • Results and interpretation

The results of the shading and radiation coefficients are detailed in the table and give an overall shading of 46%, well distributed between months and zones.

Two aspects should be highlighted:

  1. The shadow (and radiation) of the whole is almost proportional to the GCR (Ground Cover Ratio), which in this case is 50%. The wider the spacing between rows, the less shade and the more radiation.
  2. The distribution of radiation between the zones depends on the height of the panels:
    – the higher the panel height → more even distribution between zones.
    – the lower the panel height, the more concentrated the radiation in the central areas.
    – Simulation and calculations

c). Studies and calculations of agricultural production as a function of radiation.

The study by Yang et al. (2018) also establishes a relationship between yield and solar radiation during the corn grain filling period. The conclusion is that shading negatively affects crop yields. The graph showing the results of the study is attached below.

According to Yang’s graphs, the yield reduction is highly linear, so that a 47% reduction in irradiance during the grain filling period leads to a proportional reduction in yield, from 17 Mg/Ha to 9 Mg/Ha in the first case and from 16 Mg/Ha to 6 Mg/Ha in the second, i.e. reductions ranging from 47 to 62%.

Du Pont’s article compiles several studies testing corn yields as a function of shade, depending on the crop’s stage of development. She concludes that a reduction in solar radiation can have a negative effect, especially if it occurs at certain stages of the crop. He mentions, for example, that shading during flowering reduces the number of grains per ear, and that shading during grain filling reduces grain weight. The following table, taken from this article, shows the reduction in yield when the crop is shaded at different stages of development.

The sum of yield reductions in the different growth phases shows an overall reduction of 58%.

A lunar tracking system to prevent migratory bird accidents

The Moon Track system prevents migratory birds from mistaking the panels for bodies of water at night. This system is based on rotating the panels at sunset so that they always face the moon.



3- Social and economic responsibility.

Financial contribution :

  • 750 euros / MWp / year for the farmer who will cultivate the land
  • 750 / MWp / year to the farmers’ pension fund or the nearest agricultural cooperative.
  • Our initiative as a pioneer in citizen participation
  • Our social and cultural commitment
    • Each project will have a part of the perimeter with informative and educational kiosks enabling children to learn about the history of the crops developed or other kindergartens.

4- Management & dismantling warranties and agricultural updating.

Management guarantees

  • Each long lease contract signed between the developer (us) and the owner can only be transferred to a Spanish company whose corporate purpose is strictly the construction, sale and operation of the AgriVitiVoltaic farm. This avoids the domino effect of a failure of one part of the company’s projects, which could lead to the failure of all units. One company per project and one project per company.
  • Each year, the company owning its sole project will have to carry out an audit to be submitted to the landowner and the local administration so that they can jointly or separately verify that the company is up to date with payments due to its suppliers. If this is not the case, it will have a grace period of six months in which to regularize its liabilities to suppliers. If necessary, the landowner and/or the administration will have the option of appointing a private or administrative auditor to replace the operating company for the period required to update the accounts. This right of substitution is provided for when the long lease agreement is signed, in a power of attorney that will accompany the lease agreement, as well as any lease transfers that may take place during the operation of the AgriVitiVoltaic EPZ © farm. This mechanism guarantees the owner and the authorities that an EPZ farm will not be a polluting ruin in the event of lengthy bankruptcy proceedings, since annual OPEX is low in relation to sales.

Guarantees for dismantling and updating agricultural activities.

  • Operator obligations :
    • Four years before the end of the emphyteutic lease, the operator must, within a period of six months, issue a call for tenders for declassification in accordance with the legislation in force at the time, in order to restore 100% of the land to agricultural use. In this case, he automatically loses the three and a half years of sales.
    • After the launch of the dismantling tender, the operator has a further six months in which to deposit with a notary or the Escrow account an amount equivalent to the average amount of the bids, including VAT, plus 20% for any contingencies. This deposit will be used to guarantee the financing of the complete dismantling of photovoltaic installations in the event of the company’s disappearance. This decommissioning guarantee is the only one that can be given in the long term, since we don’t know what legislation will be in force at that time for decommissioning, so it’s impossible to quantify it in advance, and it’s also difficult to guarantee the existence of a long term. Forward financial entity without taking into account the change of operator during the energy operation.

  • Owner’s obligations :
    • Four years before the end of the emphyteutic lease, the owner must, within six months, issue a call for tenders to replant 100% of the land in line with the environmental farming practices of the time. If necessary, he automatically loses the three-and-a-half-year lease. It’s very likely that the agriculture practised today on the AgriVitiVoltaic EPZ © farm will not be the same as that practised in 30 or 60 years’ time.
    • Following the call for tenders, the owner will have a further six months in which to deposit with the notary or the Escrow account the sum equivalent to the average of the bids, including VAT, plus 20% for any contingencies. This deposit will be made in favor of the administration in order to guarantee the financing of the full agricultural profitability of the land if the owner sells at the end of the lease. In this case, he automatically forfeits the last three years’ rent.

The whole concept makes it possible to envisage Globally Sustainable Development in the service of the General Interest, by linking the objectives of investors to the interests of farmers and to the security of public administration, which will fear no more than generations. of ending up with abandoned photovoltaic graveyards whose dismantling would be financed by local taxes.