In a recent article in the Bay Journal, the Chesapeake's monthly environmental newspaper, senior writer Timothy B. Wheeler speculated that that the growth of large-scale solar collection fields on Maryland's Eastern Shore, at the expense of cornfields, might have "unforeseen consequences on land use, local economies, wildlife habitat and maybe even water quality." ("Solar Power's New Look: More Landscape-Friendly Siting," April 2018.)
In fact, we have enough scientific knowledge to foresee quite a few of those consequences—and they would be positive ones. For example: Cornfields are dominated by a single crop species, while the vegetation under solar fields is much more varied (native grasses, goldenrod, etc.) and thus more biodiverse. Because of these differences, the vegetation under and between solar panels provides much better habitat for wildlife—particularly for early-successional bird species, whose populations have been declining at alarming rates.
Similarly, solar fields provide much better resources than cornfields for pollinating insects such as bees and butterflies.
Cornfields are annual row crops and, of course, farmers try to keep the growth of weeds between those rows to a minimum. This means that they have considerable amounts of bare ground and thus substantial losses of soil to erosion, together with the runoff of the nutrients that spur eutrophication, a major cause of the Bay's dead zones.
On the other hand, the meadow vegetation under solar fields is perennial, not annual, and thus provides year-round cover. So it reduces erosion and nutrient runoff significantly. This is true even compared to well-managed row crop rotations using no-till management and winter cover crops.
Unlike cornfields, solar fields don't require the use of insecticides, fungicides, tillage or irrigation. Nor do they require fertilizer, whether synthetically or from manure, both of which lead to water pollution.
Solar fields provide substantially more revenue to rural landowners, with much lower costs as well as less risk. The income they generate is dependable over the long term because typical solar leases are for periods of 20 years or more.
This makes it possible for farmers to keep their land instead of having to sell it in the face of suburban sprawl. Moreover, the benefits of converting cornfields to solar reach far beyond the farm. By reducing global warming, they slow down the rising sea levels and extreme storms that threaten communities along the Bay and far beyond.
They also cut down on the air pollution from coal-fired electric power plants, gasoline-burning cars and natural-gas-heated offices. In this way they reduce one of the most important threats plaguing public health, manifested in such illnesses as asthma, toxic chemicals such as mercury, and smog.
Like a cornfield, a solar farm uses land and the sun's energy to produce something that people vitally need. But it does it with a much more positive impact on the environment—locally, across the Bay's watershed and around the world.
And, just as important, it makes possible the transition to an economy powered by 100 percent renewable energy—the critical environmental need of the 21st century.
Ecologist Doug Boucher is with the Climate and Energy Program of the Union of Concerned Scientists. His views do not necessarily reflect those of the Bay Journal.