As the number of solar parks in the UK increases, there is growing interest in the interaction of wildlife with ground-mounted photovoltaic (PV) solar panels. To date, a relatively low number of research papers have formed the basis for considerable discussion on the subject, and in some cases these have informed guidance relating to PV solar parks in the UK.
Rachel Taylor, an ecologist in our Monmouth office, has reviewed readily available papers on potential interactions between PV solar panels and invertebrates, birds and bats. The aim was to identify potential ecological issues based on research undertaken to date. The work was confined to research into interactions between wildlife and solar panels, and did not consider any land or habitat effects of solar park development.
Some sources were not available for consideration and the review is by no means definitive. We would therefore be very pleased to hear from anyone with more research or monitoring information, with a view to moving the subject forward and making sure that the design and planning of solar parks is undertaken in the most informed way possible.
In the meantime, we advocate a careful and considered approach when making ecological recommendations and planning decisions for ground-mounted PV solar parks, given the limited body of available research.
Some of the studies that have received the greatest amount of interest are principally concerned with aquatic invertebrates, birds, and bats. A brief outline of our findings is set out below.
A view that is commonly expressed is that solar parks attract aquatic invertebrates away from water bodies, and that abortive egg-laying on solar panels could give rise to impacts on local invertebrate populations. Most guidance and comments that we have come across in this regard seem to stem from a single paper in 2010 by Horvath et al. However, the experimental design and the conclusions reached in this research do not seem to support the concerns expressed, not least when modern UK PV solar panel design is taken into account.
One of the most high profile issues regarding birds and solar parks in recent years has been the effect of light reflected from mirrors at concentrated solar parks, which can singe a bird’s wings. Most of the articles available draw upon one document, by McCrary et al. (1986). The authors report on bird mortality at the Solar One facility in the Mojave Desert, a concentrated solar system, which uses mirrors to concentrate sunlight onto a central tower containing a fluid which is heated and then used to heat water, which powers a turbine. These are not present in the UK and a report released by the Committee of Climate Change states that concentrated solar systems are not suitable for use in the UK, as the technology requires intense sunlight and little cloud.
The impact of solar parks on bats has not attracted as much interest within the media. There has been some concern that there may be collision fatalities due to bats mistaking solar panels for water. A paper by Greif and Siemers (2010) looked at recognition of water bodies by bats under laboratory conditions. The researchers concluded that bats have an innate ability to echolocate water by recognising the echo from smooth surfaces, and that bats may therefore perceive all smooth surfaces as water, but there was no mention of bats colliding with the panels and the authors do not suggest that bats will be negatively affected by the mistake.
A more recent paper by Russo et al. (2012) assesses the ability of bats to tell the difference between water and smooth surfaces in the wild. It is fair to assume from the papers reviewed that although bats may confuse smooth flat surfaces with water bodies, it seems unlikely that this would have detrimental effects on bat populations. It would also seem unlikely that PV solar panels are a particular cause for concern when considered against other man-made, smooth, flat surfaces introduced into the environment.
From the research that we have reviewed, it seems likely that the majority of concerns that have been discussed in the media are not well-founded or particularly relevant to the UK; or are based on scientific experiments that were not specifically designed to evaluate ecological impacts of PV solar panels. It may be possible to make some sensible and logical recommendations in respect of survey and mitigation measures, based on the research available, but such recommendations should be reviewed on a site by site basis, taking into account the setting of the site.
The review of available research suggests that the ecological impacts of ground-mounted PV solar panels in the UK may be relatively limited and location-specific. The objectives and design of surveys and the development of ecological recommendations at ground-mounted PV parks should be considered in this context and on a case-by-case basis, to ensure that any design restrictions or mitigation / compensation measures are justified and effective.
The full research version is available to download from our Research Page
If you have any constructive comments on the paper or would like to discuss other research or monitoring that we have been unable to locate please email Rachel Taylor.
If you would like to find out more about our work at solar farms around the UK, please contact James Gillespie.
References cited above:
Horváth G., Blahó M., Egri A., Kriska G., Seres I., Robertson B. (2010). Reducing the maladaptive attractiveness of solar panels to polarotactic insects. Conservation Biology, 24: 1644–1653.
McCrary, M.D., McKernan, P. A. F., Schreiber, R. W., Wagner W. D., and Sciarrotta, T. C. (1986) Avian mortality at a solar energy power plant. J. Field Ornithology. 57(2): 135-141
Greif, S., and Siemers, B. M. (2010) Innate recognition of water bodies in echolocating bats. Nat. Commun. 2(1):107
Russo, D., Cistrone, L., and Jones, G. (2012) Sensory ecology of water detection by bats: a field experiment. PLoS ONE. 7(10): e48144