Solar

A solar power plant in Seville, Spain. Photo credit: Solar Power Plant Gemasolar, 2014

CONSTRUCTION

Unfortunately, many of the areas set aside for the construction of solar facilities are currently considered to be some of the few areas on the planet that are relatively undisturbed. This likely has to do with the fact that solar projects are often constructed in deserts – inhospitable habitat for humans, though excellent habitat for desert species. Further, mining for raw materials for cement, glass, steel, or other materials needed for either solar panels or solar facility construction negatively affect off-site species. It has also been found that “the material requirements for large-scale solar facilities exceed those for conventional fossil-fuel plants on a cost-per-unit-of-energy basis” (Lovich, 2011).

Grading and Roads

The Desert Tortoise, Gopherus aggasizii, is particularly affected by road
construction around solar fields in Nevada. Photo credit: Wildlife Profile

The construction of large-scale solar facilities generally requires clearing of the land and vegetation removal, as well as grading that leaves the landscape within 3° of horizontal. Ignoring the obvious loss of habitat, vegetation removal and landscape modification alters natural drainage channels of the land, increases runoff, compacts soil, and contributes to erosion (Lovich, 2011). Facilities also require the construction of roads, which causes habitat fragmentation and higher mortality of wildlife purely due to vehicular collisions. Habitat fragmentation impedes natural movement and gene flow, causes migration bottlenecks, and generally decreases overall range size (Lovich, 2011). Road construction can also further compact soils, which can prevent burrowing species from using the habitat because the soil becomes too dense to burrow into. Those already in the ground when soil compaction occurs can be killed or entrapped.

Dust Emissions
Any modification of desert landscapes results in higher dust emissions, which causes wind erosion, decreases soil fertility, lessens water-retention, causes abrasion to plant leaves and stems, buries plants and/or exposes plant roots, and ultimately leads to more intense winds which exacerbate dust emission problems (Lovich, 2011). All of these problems in turn affect plants’ primary production, which then lessens the wildlife’s food plant availability and therefore the habitat quality. The vulnerability of the soil caused by vegetation clearing and erosion from dust emissions can cause a greater susceptibility to invasion by exotic species that do well in disturbed habitats, and reduces secondary plant succession (Lovich, 2011).

Noise Pollution

Construction of Florida Gulf Coast University
Solar Farm. Photo credit: Fortier, 2009

An often-ignored effect of construction of solar plants is the impact of noise pollution on wildlife. During construction, noise levels can reach 110 decibels, which is within the range that causes pain for humans and is the equivalent of standing next to a running power saw. While that may not sound especially loud, 90-95 decibels is the threshold in which sustained exposure will cause hearing loss for humans (Decibel Comparison Chart, 2007). Animals that are more susceptible to loud noises (they will experience hearing loss with changes of only a few decibels) will experience detrimental effects such as a weakened immune system, reduced reproductive success, altered foraging behavior, increased predation vulnerability due to the inability to detect predators, lessened ability to communicate with conspecifics, and overall damaged hearing and possible complete loss of hearing (Lovich, 2011) Construction of facilities is when noise pollution is worst, but operation and maintenance can contribute as well - particularly if cooling systems with fans are used.

OPERATION & MAINTENANCE

Water Loss

While construction has the largest effects on wildlife species, operation and maintenance of facilities can also be detrimental. First, cooling systems use water – an already scare resource in desert habitats. As of now, there are two types of cooling systems: wet and dry. Wet cooling systems are more economic and efficient, but consume large amounts of water. Dry cooling systems use water from the ambient air and therefore use less groundwater, but have a larger footprint and therefore cause greater habitat loss and wildlife displacement (Lovich, 2011) Regardless of the type of cooling system implemented, solar facilities divert water away from infrastructure, making the solar field even less hospitable to plants and wildlife.

Electromagnetic Fields

Additionally, solar plants generate an electromagnetic field during operation. While it has not been widely studied as of yet, researchers have suggested some possible impacts, including damage to animals’ nervous systems, disrupted circadian rhythms, changes in heart function, deficient immunity and fertility, and further genetic and developmental problems (Lovich, 2011). Species that use magnetic fields for orientation could also be negatively affected.

Map of solar radiation levels in the United States. Notice the focus on Nevada and California deserts. Photo credit: The U.S. Army's New Solar Power Plant, 2009

Panels

Solar panels can also have negative effects on wildlife. As anyone who has looked at a solar panel can attest to, they are extremely reflective and thereby can increase the albedo of the desert in which they’re situated by up to 56% (Lovich, 2011). This can cause changes in local temperature and precipitation patterns, which negatively affects the local microclimate by changing wind speeds and evapotranspiration rates. Further, the concentrated beams reflecting off the solar panels can actually burn or incinerate insects and birds that happen to fly through them – a particularly disturbing finding (Lovich, 2011).

Spark of Hope?

Fortunately, researchers have found that there can be positive effects of habitat modification. One interesting find was the edge enhancement effect on certain plants due to road construction. Evidently, certain types of plants benefit from roads because they get greater dispersal and can get more water from the increased runoff from the impervious pavement or more compacted soil of the roads. Unfortunately, the increased plant production then brings wildlife to the roads, which causes more vehicular collisions and mortality for those foraging species (Lovich, 2011).

Original Figure, stats taken from Solar Energy Statistics, 2013