Utility Scale Solar Site Selection Criteria: From a County to the Owners Who Sign

Your GIS analyst starts the week with a whole county on the map. By Friday a few dozen parcels are still shaded, and someone has to decide what happens to them next.

Utility scale solar site selection criteria are the screens that get you from that county to those parcels. Developers check eight things, roughly in this order: grid capacity and distance, slope, flood zone, wetlands, soils and prime farmland, zoning and setbacks, parcel size and shape, and road access. A parcel that fails one usually drops off the list. The ones that pass become your screened parcel list.

So the best land for a solar farm is flat, dry, open ground near a substation that still has room. It sits in a county that allows solar, on parcels big and regular enough to hold the array after setbacks. Much of that ground is farmland. USDA researchers found 43 percent of rural solar farms installed from 2012 to 2020 went on cropland, and 70 percent in the Midwest.

Every guide on this search stops at the list. The next screen, the people who own those parcels, decides more projects than any layer on the map.

The eight screens, in the order they cut

Run the screens that throw out the most ground for the least work first. Grid goes first because a perfect parcel with no room on the wires isn't a site.

1. Grid capacity and distance

The distance rules are well known. YSG Solar's rule of thumb is within 2 miles of a substation and within 1,000 feet of three-phase power. Transect uses about 5 miles or less to a substation. K2 Renewables, writing for landowners, says developers look 1 to 5 miles from high-voltage transmission lines.

Distance is the easy half. LandGate points developers to available transfer capacity, which it defines as how much new power can go onto the grid at a location "without triggering congestion, curtailment, or the need for costly transmission upgrades." A substation down the road that can't take your megawatts doesn't count. We covered the cost of each extra mile in how far a solar farm can sit from a substation.

2. Slope

YSG puts the limit at a 5 degree incline for single-axis trackers. Transect says flat ground first, then 5 degrees or less, with rows facing south on sloped sites.

Nevados, a tracker maker, says developers have long treated anything over 5 degrees as unsuitable, partly because grading and stormwater work cost so much that some developers skip whole states. It now sells a tracker it says handles overall slopes up to 37 percent. Treat slope as a cost screen. Pivot Energy notes a slight slope to the south or east can even help.

3. Flood zone

FEMA's flood maps mark the Special Flood Hazard Area, land with a 1 percent chance of flooding in any year, also called the 100-year flood. Pivot says projects "usually require additional due diligence to build on a 100- or 500-year floodplain."

It's not always a hard no. YSG says a parcel on a floodplain can still work if the equipment is built strong enough and high enough, at extra cost.

4. Wetlands

Pivot is blunt: solar farms can't be built within wetlands. The U.S. Fish and Wildlife Service publishes the national wetlands map, and screening tools such as Latapult carry wetlands as a built-in layer.

Filling a wetland means a permit under Section 404 of the Clean Water Act, run by the Army Corps of Engineers. EPA says applicants must first show they took steps to avoid the impact. A wetland across one corner of a parcel usually just cuts the usable acres, which turns it into a size and shape question.

5. Soils and prime farmland

Two questions here. Will the ground hold the piles? K2 says sandy or rocky ground needs extra preparation. Nevados lists unstable soil and old underground mining among the reasons sites get thrown out.

And will the county or state object to losing the farmland? Virginia answers that in law. For solar projects up to 150 MW permitted under its small renewable energy rule, a project that would disturb more than 10 acres of prime agricultural soils, or 50 acres of contiguous forest, "will be deemed to have a significant adverse impact." The developer then files a mitigation plan with a 45-day public comment period.

Pivot makes the other side of the case: land in lower-value commodity crops, or with rocky, unproductive soil, can be a good fit.

6. Zoning and setbacks

Local government usually decides. Pivot lists the permits a solar farm needs: land use, zoning, grading, construction and electrical. K2 notes some counties require special-use or conditional-use permits.

Setbacks then shrink the parcel. Under Michigan's Public Act 233, a township ordinance for solar projects of 50 MW or more sets these minimums, measured from the perimeter fence: 300 feet from dwellings on nonparticipating properties, 50 feet from a public road right-of-way, and 50 feet from a nonparticipating neighbor's property line. YSG says that in its experience local authorities allow roughly 60 percent of a parcel to be covered once setbacks and zoning are applied.

Read the word "nonparticipating" twice. Those setbacks run from neighbors who haven't signed. The parcel next door can shape your layout almost as much as your own.

7. Parcel size and shape

PVcase puts a utility-scale plant at 6 to 8 acres per MWac, so 100 MW needs something like 600 to 1,000 acres or more. Our acres per MW breakdown shows what the federal labs measured.

Shape matters as much as size. K2 says developers want rectangular or square parcels not split by roads, buildings or easements, and that owners of several adjoining parcels can qualify together. A long, thin lot can pass the acreage test and fail the layout.

Is 10 acres enough for a solar farm?

Not for utility scale. YSG says developers generally want a minimum of 10 acres of usable land, or 200 acres for a utility-scale project. At its 60 percent coverage figure, 10 acres leaves about 6 to build on.

Ten acres can fit a small community solar project. Pivot says those typically need 10 to 20 acres or more, at about five acres of buildable land per DC megawatt.

8. Road access

Cranes, trucks and pallets of panels have to reach the site. K2 says developers prefer paved or well-kept gravel roads and direct access to a highway or county road. A parcel with no road frontage may need an easement from a neighbor, and land that floods or turns to mud in some seasons can be cut off entirely.

What the screen hands you

A county becomes a short list. A large site on that list is often several adjoining parcels, not one, and each has its own owner. Add the neighbors whose signatures change your setbacks, and the list of people you need is longer than the list of parcels.

None of the eight screens has a layer for whether those people will ever answer.

The ninth screen: who owns the parcels

Screening tools pull owner names from county parcel records. Regrid, which supplies parcel data across the country, describes the owner mailing address plainly: "the address where the tax and other assessor's communications are sent." That's the address your mail house prints.

USDA's 2024 survey of farmland owners shows how often that address misses the person who decides.

• Non-operating landlords, people and entities who rent land out but don't farm, own 79 percent of the 348 million acres of rented farmland.
• Of the land those landlords rent out, trusts hold 27 percent and family legal entities 26 percent.
• More than a third of non-operating landlords are 75 or older.
• Over the next five years, 10 percent of owned farmland is or will be placed in trust, and another 15 percent is or will be written into a will.

Put that next to your screened list. The name on a parcel that passed every screen is often a trust, a family LLC whose mail goes to an accountant, or an owner past 75 whose children will be the ones to sign. Sometimes the owner has already died, and the heirs who can sign live three states away.

A parcel whose owner never sees your letter is worth the same as a parcel that failed the slope screen. The difference is that you paid to screen it.

So add a ninth criterion to the checklist. For each parcel that passes, can your team reach the person who signs, and has that person answered?

You screened the land. Now screen for contact.

Most land teams can't answer that through mail alone. The owner of record is a trust, an LLC, an estate or someone who moved away, and the letter goes to an address nobody acts on. You don't have a land problem. You have a contact problem.

That's the part we run. We find who can actually sign for each parcel on your screened list, email every owner, follow up with the quiet ones, and tell your team in seconds when an owner wants to talk. Your team takes the call and signs. On one campaign for a developer in Georgia, 1 in 9 parcels wanted to talk about a lease once their owners were reached this way.

If you want a rough count of how many owners on your screened list have never seen your letter, put your parcel count into the calculator.