EnR Acceleration Law and Climate Law: car parks at the heart of the transition

To respond to these different challenges, the French government is accelerating the territory's transition through two pieces of legislation: the Renewable Energy Acceleration Law (AER) of 2023 and the Climate and Resilience Law (known as “Climate”) of 2021.

From today, July 1, several obligations [2] require the installation of photovoltaic panels on the roofs of buildings and French car parks. For the latter (from 500m2 of footprint) when they are new, subject to major renovations or a change in management, it will also be necessary to put in place devices promoting permeability and infiltration of rainwater. As for existing buildings and car parks, the compliance deadlines extend from 2026 to 2028. Several implementing decrees should see the light of day soon. O2D Environnement, a specialist in permeable soil solutions and a player in the transition, deciphers this new regulation which makes it possible to combine all the advantages of permeability with the production of renewable energies.

Permeable parking lots that produce renewable energy

In France, car park and roof surfaces of professional or tertiary buildings are still largely fitted out with mineral and waterproof materials. They thus actively participate in urban warming and can reach very high ground temperatures in the event of a heatwave or extreme heat. Where car parks at least have the function of allowing vehicles to park, the roofs remain largely underutilized. A real shortfall in the era of Zero Net Artificialization (ZAN), but also when cities must become more resilient in the face of global warming.

However, these different surfaces, if used well, can provide ecosystem services to their environment and thus actively participate in the transition. By installing solar shades over parking spaces and photovoltaic panels on roofs, the areas become renewable energy production zones that can be self-consumed or re-injected into the electricity network. If, moreover, the parking lot floors are permeabilized to allow water to infiltrate, the overall environmental value is highly enhanced. The infrastructure then fits perfectly with its environment, limiting the impact on the planet while meeting the needs of users. With these new obligations, the AER and Climate laws also aim to optimize existing land. The installation of photovoltaic shades on roofs and parking areas makes it possible to optimize surfaces that are already immobilized and artificialized, instead of installing huge solar “fields” on natural areas such as forests.

Indeed, by combining the devices, the benefits are multiple. First of all, the shades will protect the vehicles from bad weather but also from high heat. Via the shade produced, the comfort of users will therefore be double: the parking lot becomes more pleasant as a living area, while reducing the use of air conditioning in the cars. For building/parking owners and managers, solar panels will reduce energy bills and benefit from a self-consumption bonus. By connecting these panels to charging stations, car park managers will also be able to encourage the use of electric or hybrid vehicles. If the solar energy produced is reinjected into the network, this also promotes the greening of the French energy mix while combating potential shortages.

At the same time, the benefits of permeable soil are significant. By letting water infiltrate at its point of fall or by runoff, such a device restores the missing links in the water cycle in urban areas by reestablishing air-water-soil exchanges, while restoring the soil's functions. natural. Thus, permeabilized surfaces can contribute to the nourishment of groundwater and soil hydration, to the fight against urban heat islands (by regulating ground temperature), but also to the return of biodiversity to the city thanks to a more vibrant soil that favors soil fauna. These different benefits have been studied by O2D Environnement in various scientific studies in recent years [3].

Finally, the environmental value of eco-designed parking spaces and roofs is increased tenfold. The issues of rainwater infiltration, shading, revegetation and energy transition are in fact complementary and serve the same objective: limiting the impact of construction for a more sustainable city. Furthermore, the techniques that allow planning to take these issues into account are just as complementary. In a car park equipped with shade structures, it is sufficient, for example, to manage the flow of water differently in order to allow the infiltration of water running over the panels towards infiltration zones (permeable soil systems, valleys, trenches, etc. .).

[1] According to the European Copernicus Institute, in a press release relayed by AFP on 15/06/2023

[2] Articles 40, 41 and 43 of the AER Law as well as article 101 of the Climate Law.

[3] See the report on the recovery of biodiversity in permeable car parks and the one on the fight against urban heat islands.

Illustrative image of the article via Depositphotos.com.