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.

Project aims

We are studying how natural value and soil health in solar parks can be improved in the design phase and with vegetation management. This will result in guidelines for design and vegetation management, which will be operational through the quality certification EcoCertified Solar Label. This label guarantees preservation of soil quality in the solar field and a contribution to the recovery of biodiversity in our landscape.

The project is carried out by a consortium of Wageningen University & Research, TNO, Eelerwoude, Holland Solar and NL Greenlabel , in cooperation with solar park developers, 8 provinces, Rijkswaterstaat, and the Nature & Environment Federations. It runs from the end of 2021 until 2025.

To determine and substantiate the guidelines that are used in the label, three PhD-students are investigating the biodiversity and soil quality in 20 solar parks in the Netherlands. As part of this research, an experiment with four different vegetation management options is carried out to investigate what type of management contributes most to the restoration of natural values in the landscape. We will also research cost-effective and innovative techniques to monitor the development of vegetation, insects and other wildlife in solar parks.

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

Early on in the project, a first version of the label will be developed and tested (expected early January 2023).

In the course of the project this label will be updated based on scientific results and practical insights. By the end of the project, this will result in an EcoCertified Solar Label that is ready to use for developers and land-owners in development of plans, and that can be required by local governments and municipalities in permitting procedures.

What are we investigating in the parks?

Three PhD-students at Wageningen University are studying the (changes in the) natural values in 20 existing solar parks:

  • Luuk Scholten is investigating soil quality (e.g., vegetation growth, soil organic matter, carbon storage);
  • Timea Kocsis is investigating the importance of the park vegetation and its management for insects and other invertebrate fauna;
  • ChloĆ© Tavernier is investigating use of the parks by mammals and birds, and the conditions that are required to allow such use.

Mowing and grazing: vegetation management experiment

Part of the PhD research concerns studying the effect of vegetation management on ecological value of the solar parks. To that end, four management treatments were initiated in the fall of 2022:

  1. Mowing twice a year without removal of cuttings (common practice in Dutch solar parks);
  2. Mowing twice a year with removal of cuttings (improved mowing practice);
  3. Mowing frequency tuned to the growing conditions in the park (much improved mowing practice);
  4. On-and-off pressure-grazing with Kempen heath sheep. This breed of sheep is known to eat all vegetation, not just the tasty plants and flowers.

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 guidelines (that are currently being researched and developed), obtain the EcoCertified Solar Label. The label guarantees the solar park to have an added value for ecology and biodiversity. This way, the label provides tools for developers and local governments to establish solar parks with an added value for nature.

The label provides a surplus value for existing solar parks as well, because it provides guidelines to manage the parks in such a way that biodiversity increases.


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).