Back to Blog
Every solar developer dreams of building an array on a perfect plot of land – flat, south-facing, no neighboring landowners, obstructed public view, etc. Unfortunately, perfect plots rarely show up in this day and age. There is always something about a piece of land that must be addressed to successfully build a solar array, in any area where there is an active solar industry. In this blog, I will be discussing various issues and strategies for addressing a variety of problems that are often seen on prospective development sites. These issues are largely independent of interconnection concerns, which pose their own problems.
Slope used to be a large determining factor in determining the viability of a site. These days, solar arrays can be built on slopes of up to 9 or 10 degrees with the use of innovative racking anchoring technology. When considering building on a slope of up to 10 degrees, one must still take care to understand the underlying cause of the topography of the site. In many areas in the mid-Atlantic region, for example, high slope areas may be the result of occasional flash flooding or extreme erosion conditions. In these cases, geotechnical analysis should be performed to investigate the possibility of undercutting during such incidents. When developing sites on higher slopes, always contact racking providers early on to get their professional opinion on whether or not their product will work for your application.
In areas where glacial till has occurred, developers often encounter boulders and rocky debris on sites that otherwise look ripe for solar. While it can be time consuming and expensive to move large boulders, such sites may provide advantages that can make up for this. Rocks and boulders can be used on-site for a variety of purposes. Depending on the size and consistency of the materials, they can be used for gravel, to create a boarder outside the fence line providing screening along with vegetations, or as substrate for drainage ditches and retention ponds. Depending on the price and availability of machinery, it may be more cost effective to crush rocks on site for gravel, than to ship it in from elsewhere.
Wetlands, Waterways, and Bodies of Water
While it can be a development headache to deal with streams or wetlands crossing on an otherwise perfect solar site, they do not always have to be a deal breaker. Buffers do create issues, but plots with wetlands can still be developable if the property is not otherwise usable.
Floating photovoltaics have also been gaining popularity in the solar industry in recent years. Water treatment plants, ponds, and reservoirs provide acres of addressable area for solar, and the addition of floats to the surface of the water can reduce the average temperature, prevent evaporation, and help to mitigate algae build-up. In parts of the world, where there is little available dry land, floating solar can be the only option available. This approach has become especially popular in places where rice is the dominant agricultural product, allowing for the paddies to regain nutrients lost over years of planting. Once, an array reaches its end of life, the paddy may be ready for further planting.
Artificial waterways like those seen for irrigation canals and open-air municipal water distribution may also be usable for solar through the use of racking that spans the width of the channel. This approach may be most useful in arid climates where evaporation is of special concern.
Agrivoltaics have also gained popularity in the solar industry in recent years. However, it is important to keep in mind that there is no ‘plug-and-play’ approach for agrivoltaics. This is because each site must be tailored to the particular crops or animal involved. Therefore, when considering an agrivoltaic solution on an actively farmed plot, the developer must do everything that they can to understand the use- case from the farmers themselves. In many cases, row spacing must be tailored to the operation of farming equipment. Some crops prefer the shade provided by solar panels and can therefore be placed beneath the racking. Other crops need direct sunlight and must be placed within rows. If animals are the main product on a farm, racking, wiring, and inverter/combiner placement must all be tailored to prevent damage to the array or harm to the animals. These considerations will often require a lowering of energy density and/or the use of more materials. This increase in materials and engineering cost can be offset by the dual-use aspect of the site, preserving the agricultural zoning designation in some jurisdictions.
Previous Building, Development, or Environmental Remediation
Capped landfills have been known to be a great location for solar for some time now. There are other types of brownfields that may also provide benefit from solar. For example, abandoned industrial and commercial locations can be taken advantage of in a variety of ways. Decommissioned factories and empty commercial buildings have started to litter the American countryside in recent years, and these blemishes can be converted into ground mount solar arrays with relative ease. This is due to commercial and industrial zoning status, as well as positive public perception of making use of what was previously an eye sore for the municipality involved. However, when considering development of any kind of brownfield, it is important to review all state and federal documentation of previous and ongoing remediation efforts. Some remediations can be conducted in parallel with solar development, while others may delay or halt the permitting process. The federal government does approve of the use of contaminated or remediated land for solar, but a developer will always have to interface closely with organizations like the EPA and the Army Corps of Engineers throughout the development lifecycle to ensure there are no pitfalls during development and construction.
When considering development on an atypical parcel, it is critical to engage engineers and EPCs as early as possible to correctly understand and budget for whatever strategies are required. While many of the solutions discussed here require increased capital costs, they can also provide financial benefit that would not exist otherwise.
Written by Matthias Dean-Carpentier