Project

EcoCertified Solar Parks

Much can be done to increase the natural value of solar parks. Light on the soil and vegetation management are crucial factors therein. What are the basic requirements for nature inclusive solar parks, and how can those values be realised in existing solar parks? That is the aim of the project EcoCertified Solar Parks.

About the project

We are investigating the ecological value and soil health of existing solar parks compared to surrounding grasslands, and how solar park design and vegetation management can help preserve and enhance natural value and soil health in both new and existing solar fields. The results will lead to guidelines for the design and management of solar parks.

Wageningen University & Research, TNO, Eelerwoude, NL Greenlabel and 10 solar park developers affiliated with Holland Solar are working together as a consortium to carry out this project. In addition, eight provinces, Rijkswaterstaat, and the Nature & Environmental Federations (NMF) are contributing to the project. It runs from the end of 2021 to the end of 2025.

To determine and substantiate the guidelines that are used in the label, three PhD candidates from Wageningen University & Research are investigating soil health and above- and below-ground biodiversity in around twenty solar parks across the Netherlands. A management experiment has been carried out as part of these studies to determine which management practices lead to improved ecological value within solar parks while also being practical. In addition, innovative monitoring methods are being developed to track flora and fauna in solar parks, addressing the current challenges of high costs and time consumption. The results will be published in scientific articles by the involved researchers.

The ecological guidelines will be integrated and evaluated for societal and economic feasibility. In addition, the groundwork will be laid for further development of knowledge regarding nature-inclusive solar parks after the project is completed.

The EcoCertified Solar Label

As of July 31 2025, the guidelines are operational through the label EcoCertified Solar Parks van NL GreenLabel by NL GreenLabel. The label supports the efficient development of solar parks that go beyond merely generating renewable energy. It ensures that solar fields have a positive impact on local flora and fauna, and that soil health is preserved — all through a practical approach that doesn’t delay implementation but rather accelerates it.

The EcoCertified Solar Parks label can be mandated by governments and can serve as a tool for developers and landowners in planning, design and vegetation management.

What are we investigating in the parks?

Three PhD-candidates at Wageningen University are studying natural values in 20 existing solar parks, each compared to intensively and extensively managed grasslands in the immediate surroundings:

Luuk Scholten is investigating soil health: soil life, vegetation growth, soil organic matter;
Timea Kocsis is investigating the vegetation composition and abundance of insects and other arthropods;
Chloé Tavernier is investigating use of the parks by mammals and birds.

Mowing and grazing: the importance of vegetation management

The PhD candidates are also investigating the impact of vegetation management on the ecological value of the solar parks. To this end a management experiment was conducted between autumn 2022 and autumn 2024, in which both the effect and the practical feasibility of four different management approaches were studied:

vegetation cuttings (standard management);
(e.g., to promote flowering);
, meaning mowing and removal tailored to the park's growing conditions and seasonal variation;
— resulting in reducing grasses and promoting flowering herbaceous vegetation; and resulting in all vegetation being eaten, including under the panels and even the less palatable plants, particularly under high grazing pressure.

Mowing with removal, result-based management, and pressure-grazing were all found to be suitable strategies for enhancing ecological value in solar fields. For all of these management types, it is important to always leave a portion of the vegetation unmown or ungrazed. Permanent sheep grazing and mowing without removing the cuttings are unfavorable for achieving ecological benefits. For further details, see the final project report (2025) on the project page of Consortium Zon in Landschap (Dutch only).

Space between panels or space for natural elements?

Another relevant subject in this study is the use of space in a solar park. Assuming a set-up of panels where soil quality is maintained at a minimum standard (see soil test under publications below), a choice still has to be made between more space for nature between the panels on the one hand, and less space between panels but more space for natural elements around the panels on the other hand. Think of naturally managed hedges, ponds for amphibians, and wide borders with herbaceous vegetation. The research will provide insight in whether and how high natural values can be achieved between and perhaps even underneath the solar panels.

Managing existing and designing future solar parks

Developers that build and manage a solar park according to the EcoCertified Solar Parks guidelines , can obtain the EcoCertified Solar Parks certificate. The certificate guarantees that ecological added value is incorporated into the design and management of the solar park. In this way, the label supports developers and governments in realizing solar parks that are both widely supported by society and ecologically responsible. The EcoCertified Solar Parks label also offers added value for existing solar parks, as it provides practical guidance for management practices that promote biodiversity.

This project is carried out with a Topsector Energy-grant from the Dutch Ministry of Economic Affairs and Climate Policy, carried out by the Netherlands Enterprise Agency. The specific grant for this project is MOOI round 2020 (project MOOI-22004).