Q&A Courtesy of CERTs
On Zoning Ordinances
Q: Is there a solar zoning best practice guide or model we could reference?
A: Yes! The Minnesota Association of County Planning Zoning Administrators has published the Minnesota Grow Solar Local Government Solar Toolkit to their website.
Q: What is an appropriate seed mix?
A: The Board of Soil Water and Restoration has established appropriate seed mixes for Minnesota. Specific Solar-for-Pollinator seed mixes for three Minnesota regions include:
Q: What kinds of questions should landowners ask of developers around establishing pollinator plantings?
A: Landowners should have something about developers being responsible for establishing and maintaining the pollinator habitat over X time period / until it’s established.
Q: What about Palmer Amaranth in seed mixes?
A: Seed mixes should be locally sourced from Minnesota providers. Palmer Amaranth is considered a noxious weed and is on the Minnesota eradicate list. More information.
On Solar Decommissioning/Hazardous Waste
Q: Does our county need to think about mitigating solar as a hazardous waste at the time of decommissioning?
A: It’s complicated! Read more.
Q: What about panel recycling?
A: All solar panels contain at least one rare or precious metal: tellurium, silver or indium, and often several, which makes it likely that they will be recycled at the end of their working life, which is at least 20 to 30 years. Read more.
Q: Is there any official state guidance on decommissioning?
A: In August 2018 a workgroup submitted an official Solar and Wind Decommissioning Working Group Report and Recommendations Report to the Minnesota Public Utilities Commission as part of Docket 17-123. That report can be found here.
Q: What about solar and glare, particularly around airports?
A: Minnesota has airport zoning laws to, amongst other things, protect airports from incompatible land uses near the airport. These laws require local communities with an airport to adopt airport zoning in order to be eligible for state and federal funding sources. Part of the standards for this zoning is “Zone C” which has a 5,000 or 10,000 foot radius from runway and has these restrictions:
- No use shall be made of any land in any of the safety zones which creates or causes interference with the operation of radio or electronic facilities on the airport or with radio or electronic communications between the airport and aircraft, makes it difficult for pilots to distinguish between airport lights and other lights, results in glare in the eyes of pilots using the airport, impairs visibility in the vicinity of the airport, or otherwise endangers the landing, taking off, or maneuvering of aircraft. (MN Rules 8800.2400 Subp. 6)
- The concern with solar facilities near airports is the glare they can cause and they are generally restricted by airport zoning adopted at a local level. MnDOT acts as a technical resource to these communities by providing guidance on the use of the SGHAT to meet the federal policies in the link above. We don’t have a formal approval process, but will assist communities in how to use their airport zoning, and the Solar Glare Hazard Analysis Tool (SGHAT) to ensure that proposed facilities are compatible with the airport. The FAA “strongly encourages” use of the tool in the area around the regulated airport lands but does not require it.
- This document explains the FAA criteria for determining if a proposed facility is compatible using the SGHAT tool. It is found here.
- More resources:
On Life Cycle Emissions
Q: What are the lifecycle emissions for solar?
A: Solar power crossed a carbon threshold in 2018. Read more.
On Stray Voltage
Q: What about solar causing stray voltage?
A: CERTS put together a blog post about the Stray Voltage Guide.
On Property Values
Q: Do solar arrays decrease surrounding property values?
A: There has not been a national study on property values to surrounding properties. There is a study for Chisago County here and further research has been done by the University of Texas at Austin, view it here.
On Solar Leases
Q: Are there model solar leases?
A: Yes, view the UMN Law School Guide to CSG Leases here.
On Siting Rules
Q: How do solar and wind siting rules differ?
A: Solar and wind differ in siting rules and which level of government has jurisdiction. Only 15% of all permitting for solar is local. If a wind project is less than 5 MW it is local and 25 MW and greater is state; between 5 MW and 25 MW, the county can assert jurisdiction by becoming a wind delegated County. For solar, under 50MW is local and 50 MW and over is regulated by the state energy permitting process. (Minn. Stat. 216E.01, subd. 5 and 216E.03, subd. 1
If a large-scale solar energy facility is larger than 50 MW, then the project developer must apply to and receive from the PUC a site permit. If the solar energy facility is smaller than 50 MW, then it may apply to the appropriate local unit of government (the county and/or city) for a site permit. Minn.Stat. Sec. 216E.03-.05 (2018). Solar projects between 25 and 50 MW require preparation of an Env. Assessment Worksheet by the Env. Quality Board. Projects between 5 and 25 MW are subject to discretionary EAW at the request of the application, localg government or a citizen petition process. (Minn. Rules 4410.4500; 4410.4600, Subp. 3. An EAW is also required for land conversion projects that convert more than 80 acres of ag land, native prairie, forest, or naturally vegetated land. (Minn. Rule 4410.1100).
Q: How does a county assert jurisdiction and become a delegated county?
A: A delegated county must have a minimum of the state permitting standards though they may be stricter. AND, the state needs to approve them being delegated. A county can’t just be delegated without an approval process through the state. See page 4: https://www.revisor.mn.gov/statutes/cite/216F/pdf
On Storm Water
Q: How does utility-scale solar affect storm water run-off?
A: The MPCA requires that all construction projects that disturb 1 or more acres of land apply for a Minnesota NPDES/SDS Construction Stormwater General Permit. Solar projects must follow the permanent stormwater management rules and regulations of the permit. However, because solar farms—particularly the panels— have unique characteristics, not like building a building or road, the MPCA allows for the use of the “disconnected impervious credit method”, which often results in a reduction in treatment volume required. The design of the permanent stormwater management system must first try to utilize volume reduction practices such as infiltration. If it is determined that volume reduction cannot be accomplished due to prohibitions found in the permit, other types of permanent stormwater management such as wet sedimentation basins or filtration systems (e.g. sand filters) must be constructed.
Water Volume Credit to Solar Projects with Vegetation: Solar projects that use traditional elevated solar panels are unique because they contain an impervious surface (elevated solar panel) that often have a pervious surface (vegetation) underneath the panel. It should be noted that this volume credit for solar sites is only available to those site that are vegetated beneath and between panels and excludes sites that have rock bases. This configuration raises challenges when addressing stormwater runoff and the design and construction of a permanent stormwater management system due to the relationship with the solar panel and underlying surface. Since the standard calculation for the water quality volume (1 inch times the impervious surface) required by the permit does not recognize the vegetated surface left in place under the panels, the water quality volume calculation may be done using the disconnected impervious credit method located from the Solar Panel Calculator on the MPCA’s Information for determining stormwater management impacts for solar projects webpage. The disconnected impervious credit method uses an Excel spreadsheet to calculate 1) the total water volume required credited and 2) the remaining water quality volume to be treated. Read more.