Solar Farms – Biodiversity Hotspots?

Solar farms, or parks, are going to come in for a lot of flak. Photovoltaic panel prices are a third of what they were three years ago. Generous government support and ambitious targets mean that they’re sprouting all over the countryside. For developers and landowners they’re a no brainer, offering spectacular guaranteed yields. They seem to be a much better solution to meeting our renewable obligations than wind farms, too.

Everyone loves the idea of renewable energy, but the reality can be less attractive. Particularly before landscaping, solar farms can look pretty enormous and industrial. The visual impact of solar farms is a difficult thing to assess, and provokes fierce argument. A proposed site might look fine on a map if it’s not visible from any “important” or regularly used sites or footpaths. If you live in the one house directly overlooking it you might feel differently.

Many developers are motivated by purely economic interests and fail to engage local communities. Worse, they just ignore them, knowing they can get planning permission on appeal if necessary. The planning process is struggling to balance local opposition with national policy. We can take some of the heat from this process by improving the way solar farms are established and run.

Biodiversity in solar farms
Is this a biodiversity hotspot?
Mitigation requirements are generally modest, and mostly relate to hedges and hedge planting. They should be more ambitious. Sure, reinforcing, planting and letting hedges grow is helpful, but why not do more? Solar Farms actually represent a great opportunity to create biodiversity hotspots. The green deserts they replace are generally “improved grassland”, and have very limited value for biodiversity – contrary to most people’s perception. Solar farms, surprisingly, can be much more interesting.

For a start solar farms are fenced, which prevents destructive larger mammals (including humans!) getting in. This is great for flora, reptiles and ground nesting birds, for example. There’s also typically a margin between a surrounding hedge and the security fence. Why not establish a floristically enhanced margin here? Or if you were keen to encourage owls, for example, plant tussocky grass to help the vole population.

Currently, the areas between and around solar panels in most sites are either sprayed off with herbicide or cut regularly, to keep grass and weeds from obscuring the panels and scrub from getting established. Why not have grasses and wildflowers there instead? Although they will actually need less management, planners should require a management plan for these areas too. The aesthetic and environmental gains are obvious. There are also economic advantages; the cost of maintaining a carefully planned wildflower and grass mix is much lower than repeated large scale spraying or grass cutting.
These areas can also be tweaked to encourage particular wildlife. Perhaps the local community would like to encourage skylarks or a rare type of bumblebee (which is happening at one of the sites we’re involved with). The plant species can be selected and managed to suit.

The layout of solar farm panels can be helpful for biodiversity, too. Directly below them is dry, shaded and sheltered. At the base of the panel there is water runoff and more light, and in front of each row light but less water. These micro-habitats are ideal for encouraging a tremendous diversity of flora and, ergo, wildlife.

When stipulating planting schemes, planners can also be picky about provenance. It’s a great opportunity to help British suppliers of plants and seeds – like Habitat Aid! – as well as to do the right thing ecologically. Let’s learn from Ash Tree dieback. Hedge plants for solar farms shouldn’t just be native species but sourced from British stock grown in Britain. We can be even more local with wildflower and grass mixes. We can supply seed harvested from sites all over the country.

There are other potential uses for solar farms. Use orchard trees as part of any screening planting – and why not plant them with local varieties of fruit tree? I know of one site where they’re rearing queen honeybees behind the fencing, undisturbed by vandals and badgers. This stuff isn’t unreasonable or unrealistic. We are partnering two of the best solar farm developers in the country who are doing just this kind of thing: