Soil is the lifeblood of agriculture. It is a precious natural resource much like freshwater. Both are necessary for the growth of crops we consume and for a balanced ecosystem. Among the many things that differentiate these two resources are their lifecycles. The natural life cycle of freshwater occurs frequently on more of an annual or biannual timeframe. Topsoil, in its natural state, takes much longer to be established and involves many forces of nature to reach its peak condition. This brings up an often debated question about the relationship between solar arrays and the soil of agricultural lands: is it a matter of conservation or preservation?

One aspect of soil conservation is the careful use and management of a resource that could ultimately be depleted. An example is a farmer planting a cover crop or utilizing “no-till” planting techniques to maximize soil retention in the fields. Preservation on the other hand strives to retain the soil as it is, keeping it protected from effects like continual nutrient depletion due to harvesting. In this article we will discuss ways in which solar arrays can actually help contribute toward preserving topsoil for future agricultural use.

Soil preservation through community solar array development can be achieved in ways that may not be so obvious to us. There are three general considerations to be reviewed when planners and/or environmentalists among us are confronted with land use and development pertaining to solar farms.

They include:

1.      The ability for the topsoil of an agricultural field to rest and be rejuvenated over the life of a solar farm is valuable as a restorative effect.

Typical modern-day agriculture practices often result in the depletion of soil nutrients. Practices such as cash crops have become a demanding type of farming (i.e., corn and soy). Solar array projects can help re-establish nutrients that have been depleted from our precious agricultural soils. Instead of the land being slowly exhausted of essential nutrients, soil structure, and vegetation, the soil is better positioned to relax and replenish over the serviceable life of a large-scale solar array (about 25 - 30 years).

The establishment of meadowlike vegetative cover beneath large solar array systems positively impacts the performance of the land. The thick, lush vegetative growth of meadow grasses and plants helps slow down stormwater runoff and thus increases the amount of rainwater absorption into the ground. It also minimizes and can eliminate sediment transport by means of erosion control protection, which is essential to maintain the topsoil structure of the fields.

2.      Allowing the area occupied by the solar array to become a habitat for wildlife to thrive, supplying food and cover that would otherwise be absent for most of the year with cash crop harvesting.

With proper planting mixes the maintenance of vegetation can help to protect the integrity of the soil. The upkeep of the plantings can be minimized to one required cutting each year in early spring and the cuttings can be left to work back into the ground and allow for the renourishment of the soil. Left to grow throughout the rest of the year, the vegetated understory of the solar array serves as nesting grounds, food sources, and cover for wildlife at critical points in nature’s annual lifecycle. Providing flowers for pollinators and other insects is crucial to a healthy natural environment. The fruits and seeds of the meadow provide a source of valuable food to all forms of wildlife - birds, reptiles, insects, and mammals alike. And while the composition of heavy vegetation offers cover for rearing up young creatures, animals of prey such as foxes and hawks ultimately benefit from a bountiful source of small mammals and birds.

3.      Income generated by landowners of solar arrays preserves rich soil for future farmers.

We are a steward of the land in the natural ecosystem. Relaxing the soil and regenerating it with nutrients improves conditions for the future operations of farmers to come. A farmer who owns a large tract of land is often up against hardship. This includes potential loss of land due to tax burdens or the unpredictability of weather and crop yield. In many cases, a landowner is susceptible to selling the farm against their will which often results in non-agricultural development. When a farmer can utilize a portion of their land to generate needed income from a consistent source like the sun, they benefit in not only saving the family farm but enriching the land for future farming of the soils within the footprint of the solar array.