A power plant boosts biodiversity. Does that really sound credible?
This is of course somewhat overstating the point, but in the case of solar parks it is actually true: They often increase the biodiversity of an area compared to the situation before. It is especially the case for previously arable land.
How come? To start with, such projects are generally built on agricultural land.
Many of us associate a field with something natural; a place where many animals feel at home – with a construction project, on the other hand, we think of something unnatural and see a threat to biodiversity. In actual fact, from a conservation perspective, the quality of intensively cultivated arable land is not really any better than that of a supermarket parking lot: Crops are sprayed, the soil is fertilized and machinery such as tractors make life difficult for the animals. Or, put another way, a bird that broods in a field often does so for the last time.
What is different about a solar park?
The proportion of sealed land is incredibly small and the undeveloped land can be turned into a high-quality conservation area. The result is real nature – largely free of human influence. And numerous studies have proved that the modules do not disturb most species or a habituation effect can quickly take hold. Then there is the fact that we mainly use land that does not produce high agricultural yields anyway due to its soil quality. Incidentally, surveyors also take into account the impact of a solar park on the visual landscape.
Is it even possible to objectively assess the impact of solar parks on the visual landscape?
There are set criteria used by the surveyors to assess aspects such as diversity, individuality and beauty. The bottom line is that solar parks break up purely agricultural landscapes and create variety. As a result, the human eye also benefits. A carefully planned planting and care concept naturally further increases this effect.
Are the measures for greater biodiversity the same for every solar park?
No, we draw up an individual concept for each solar park. There are overlaps; for example, we generally sow highly blossoming regional seeds. Yet the key factors are the existing species inventory and habitat potential.
Incidentally, the aim of most measures is not just to benefit one specific species, but biodiversity as a whole. Let's take the example of the skylark: Assuming that we create spaces for breeding grounds and wildflower strips as a feeding habitat, these measures will not only help the skylark. They will equally offer insects, small mammals, reptiles or other bird species high-quality habitat structures.
Huge technical progress has been achieved with the modules: We can now generate twice as much power on the same area as we could ten years ago.
Plants and animals live undisturbed because humans and larger animals have no access. Fences generally have a distance of about 20 cm to the ground so that small creatures can still get into the solar park (so-called small animal passages). In some regions, a so-called wild boar-proof fence must be built to protect flocks of sheep from wolves.
Hedges and shrubs are planted in order to connect individual habitats with one another and create high-quality structural diversity (a biotope complex) aimed at species conservation.
A solar park seals less than 1% of its total area. Only the posts for the modules take up space. At very large solar parks, fixed stations may be added (inverter station(s) / transformers).
Plants and animals also live beneath the modules because light can also get through here. What cannot be seen from above is the fact that there is clearance to the ground of at least 80 cm. The abundance of insects is an important food source for many breeding bird species.
Shepherds can use the site as pasture, and thus maintain the land in a natural way.
Many construction projects are supervised by independent environmental specialists. They monitor whether conservation measures are carried out properly and in compliance with laws and regulations.
The honeybee is one of the most important working creatures of all and, like many other pollinating wild bee and insect species, it will find a diverse paradise in the solar park. Regional honey is obtained from some parks.
We sow regional seeds. This creates a new and natural habitat adapted to the location for many plants and animal species – sustainably and often for over 20 years. Depending on the location, an especially high density of species can be observed among grasshoppers, butterflies, reptiles and breeding birds, in particular.
A solar park is like a health cure for the soil: Fertilizers and pesticides are not used, and the site is not managed by any mechanical equipment such as tractors. Humus increasingly forms, which not only binds CO2, but also increases the fertility of the soil in the long term.
The larger a site is, the more likely it is to provide habitats for rare and protected species (such as sand lizards or hoopoes).
If solar parks often improve the biodiversity of an area anyway, especially when adhering to the additional measures – does EnBW’s commitment still go beyond what is required by the authorities?
We are seeing that the pressure to comply with regulations is increasing with the number of photovoltaic sites. Measures that project developers carry out voluntarily in a park are often already part of the regulations in the next project. It is nonetheless important to us to seize the environmental opportunities associated with a solar park regardless of official regulations. Many of these aspects are also included in the so-called voluntary commitment to good planning of photovoltaic sites – an initiative launched by the Association of Energy Market Innovators, to which we have signed up.
What exactly does this voluntary commitment involve?
We take a holistic approach to the planning of a solar park. Let’s take the space between the module rows: From a purely conservational perspective, it would make sense to follow the principle “the bigger, the better” – and this of course would require the largest possible space. We therefore keep within sensible limits. As a result, we use less space to yield the same amount of electricity.
Another example involves breeding habitats of certain species such as skylarks. Our aim is to keep them on the site of the solar park rather than taking external measures for them. Incidentally, both examples are in line with the prevention principle as enshrined in environmental law. According to this principle, fewer interventions in nature should be preferred to compensatory measures.
People are generally not given access to solar parks. Does the possibility nonetheless exist to gain an insight?
In June 2021, the nature magazine GEO held its annual Day of Nature. We joined in the fieldwork in two – highly different in terms of biodiversity – EnBW solar parks (only available in german) and organized virtual insights for all interested parties. You can find out more about the initiative and biodiversity in our solar parks on our website page Solar park habitats (only available in german).
Depending on the coronavirus situation, we also offer guided tours around selected solar parks (only available in german). It goes without saying that we also take into account breeding times here and keep to set areas so as not to disturb the wildlife.