Siting a 180 MW Solar Project on Prime Farmland
A 180 MW solar project is proposed on 1,600 acres of prime farmland in a county where agriculture generates $410 million annually. The developer offers $1,100 per acre per year for 30 years, 45 construction jobs, and $2.8 million per year in county tax revenue. An alternative is a 240-acre brownfield 6 km away, but interconnection limits cap it at 35 MW, cost per MWh is 22% higher, and remediation would take three years. Opponents cite food security and viewshed; the county has lost 9% of its farmland since 2000 and the soils are Capability Class I–II. State law requires 40% renewable electricity by 2030. The county board must recommend a site or a condition set. A public hearing is scheduled in three weeks, and the developer wants a decision before the federal tax credit step-down.
1. Compare the land-use efficiency and opportunity costs of the two sites, and explain what 'energy sprawl' means in this context.
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Land-use efficiency. The farmland site produces 180 MW / 1,600 acres = 0.1125 MW per acre (about 8.9 acres per MW). The brownfield produces 35 MW / 240 acres = 0.146 MW per acre (about 6.9 acres per MW). The brownfield is denser, but it is capped at 35 MW by interconnection, so it cannot substitute for the whole project.
Opportunity cost. The county must compare what each acre gives up. The lease pays $1,100 per acre per year; if typical net farm income on these soils is $200–$400 per acre, the lease is attractive to the individual owner, but the county loses agricultural output and associated agribusiness activity, not merely the landowner's margin. Tax revenue of $2.8 million per year and 45 construction jobs are partly temporary or offset by service costs.
Energy sprawl is the low-density land conversion associated with diffuse energy sources. Solar typically uses 3–7 acres per MW, so siting choices matter: brownfields and rooftops avoid conversion, while farmland trades soil for energy. Compare sites in MWh delivered, not MW nameplate, because capacity factors and interconnection losses differ.
2. Evaluate the food-security objection and propose conditions that could make the farmland site acceptable.
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Is food security a strong objection? Partly. Food security is primarily about household income and access, not the proximity of production, and a county does not feed itself from 1,600 acres. But prime soils are finite, locally specific, and effectively irreplaceable; once graded and compacted, Class I–II soil is not restored by decommissioning. The 9% farmland loss since 2000 shows the cumulative trend, and concentrating 1,600 acres in one block has more visual and drainage impact than the acreage alone suggests.
Conditions that could make it acceptable:
- Agrivoltaics: elevated panels with sheep grazing or shade-tolerant crops, keeping soil in production and reducing mowing.
- Soil protection plan: no grading of Class I land, topsoil stockpiling, limited impervious cover, drainage-matched layout.
- Decommissioning bond sized to removal and recycling costs, held in escrow for 30 years.
- Mitigation: permanent easements on equivalent or better farmland elsewhere at a 2:1 ratio.
- Glare, viewshed, and pollinator habitat requirements, plus setbacks from residences.
With these, the farmland site becomes a conditional approval rather than a binary yes or no.
3. Recommend a course of action and justify it against explicit criteria.
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Recommendation: a tiered portfolio.
- Approve the brownfield first for its 35 MW, even at 22% higher cost, because it converts a liability into an asset and avoids greenfield impacts. The higher $/MWh applies to a small share of total capacity.
- For the remaining 145 MW, approve the farmland project only with the condition set above: agrivoltaics or a soil protection plan, a 2:1 farmland mitigation easement, a decommissioning bond, and a glare and viewshed plan.
- Fund an interconnection study now; if the brownfield can be upgraded to 70–100 MW, shift capacity there and shrink the farmland footprint.
Criteria: total cost per MWh, acres of Class I–II soil converted, permanent versus reversible impacts, progress toward the 40% by 2030 requirement, and local fiscal effect. Treating the two sites as substitutes misses the point: they are complements, and the sequencing - brownfield first, farmland with mitigation second - is what makes the 2030 target achievable without treating prime soil as disposable.