CY33-26

Request of ERM on behalf of CenterPoint Energy, the property owner, for a final plat review of Centerpoint Energy Mankato First Addition, and for a conditional use permit to allow for a hydrogen facility that uses energy from a 1 megawatt on-site solar panel array on a property zoned M-2, Heavy Industrial. The subject property is described as part of the South Half of the Northwest Quarter of Section 5, Township 108 North, Range 26 West; AND, part of the South Half of the Northwest Quarter of Section 5, Township 108 North, Range 26 West; AND, a tract of land located in the South Half of the Northwest Quarter of Section 5, Township 108 North, Range 26 West; AND, part of a parcel lying within the Southeast Quarter of the Northwest Quarter, Section 5, Township 108 North, Range 26 West, all located in the City of Mankato, Blue Earth County (2400 N. Riverfront Drive, BE County PID’s R010905176004, R010905176003, R010905176002, R010905176001).  
 

The applicant is ERM, on behalf of CenterPoint Energy.

The applicant is requesting a final plat review of Centerpoint Energy Mankato First Addition, and a conditional use permit to allow for a hydrogen facility that uses energy from a 1 megawatt onsite solar panel array on a property zoned M-2, Heavy Industrial.

The subject property is described as part of the South Half of the Northwest Quarter of Section 5, Township 108 North, Range 26 West; AND, part of the South Half of the Northwest Quarter of Section 5, Township 108 North, Range 26 West; AND, a tract of land located in the South Half of the Northwest Quarter of Section 5, Township 108 North, Range 26 West; AND, part of a parcel lying within the Southeast Quarter of the Northwest Quarter, Section 5, Township 108 North, Range 26 West, all located in the City of Mankato, Blue Earth County (2400 N. Riverfront Drive, BE County PID’s R010905176004, R010905176003, R010905176002, R010905176001).

The subject property is currently in use by CenterPoint Energy Minnesota, as an industrial use. The subject property also includes a portion of agricultural land used for row cropping.

The subject property is currently zoned M-2, Heavy Industrial District.

The Planning Commission reviewed the preliminary plat at their February 25th, 2026, meeting. Final action on that request occurred at the March 9th, 2026, City Council meeting. 

There are multiple wetlands located on the subject property. One wetland area was delineated on the southern property boundary. A second wetland was noted to be centrally located on the southern half of the site, directly east of the railroad track termination. The third wetland was delineated along the southwestern property boundary, just north of the railroad track as shown on the proposed preliminary plat. 

The applicant proposes no impacts to the three delineated wetland areas depicted on the approved preliminary plat. 

The subject property is currently served by public utilities.

The applicant, ERM, on behalf of CenterPoint Energy, is requesting a final plat review of CenterPoint Energy Mankato First Addition, and a conditional use permit to allow for a hydrogen facility that uses energy from a 1 megawatt onsite solar panel array on a property zoned M-2, Heavy Industrial. The subject property is located at 2400 N. Riverfront Drive. 

The Preliminary Plat of "CenterPoint Energy Mankato First Addition" was approved by the Planning Commission at their February 25th, 2026, meeting. Followed by City Council approval at their March 9th, 2026, meeting. 

The applicant is seeking to plat the subject property in order to further develop the property in two construction phases, with a solar array and a green hydrogen production & storage facility. As the site preparations and power supply (the solar array) for the hydrogen power facility are regulatorily required to be in place prior to the hydrogen facility itself, construction will be separated into two phases. Phase 1 will include site preparation, installation of erosion and sediment controls, initial grading, and installation of the Solar Array. Phase 2 will include hydrogen production and storage facility construction, final grading, and site stabilization. Additionally, the applicant attests that Best Management Practices (BMPs) will be implemented throughout all phases to prevent sediment discharge and protect water quality. 

Phase 1 is scheduled to commence in the 3rd quarter of 2026 and Phase 2 is anticipated in the 4th quarter of 2026, although the applicant notes that the intended timeline may be subject to change due to typical development impediments.  

Previous Site Plan Review:
The proposed project, largely as it, was previously reviewed by the Site Plan and Traffic Advisory Committee on 06/09/2026. At this time, the Committee provided a series of comments to the applicant and subsequent responses to said comments then provided by the applicant. The request was withdrawn prior to Planning Commission review and resubmitted for the July 2026 cycle. With resubmittal, some minor modifications were made, which are summarized as follows:

• An updated Drainage Report dated June 15, 2026, has been provided. The applicant made modifications based on feedback provided by Public Works / Construction Services Staff. 
• An updated narrative from Muska Electric for the glare study has been provided. 
• A narrative has been provided by Muska Electric to accompany the Solar Decommissioning Estimate.
• The originally provided narrative received minor edits to increase the degree of detail within multiple sections. 
• The applicant has provided a Developable Area Map which distinguishes between developable and non-developable land for the purposes of Parkland Dedication calculations. 

Final Plat:
The proposed Final Plat mirrors the approved Preliminary Plat, as it proposes the creation of a one-lot, one-block, subdivision containing approximately 14.83 acres. As the property is currently unplatted, subdivision approval is required to bring the parcels into conformance with City subdivision regulations and to support current and future development on the site. Of note, there are no new public dedications proposed with the plat.

The proposed final plat depicts 10' standard drainage and utility easements around the subject parcel.

The approved preliminary plat showed multiple wetlands located on the subject property. The applicant has received a Notice of Decision for a "no-loss" decision under Minnesota Rule 8420.0415. Subpart A. Based on this finding, the proposal will not impact existing wetlands located on the subject property.

As was noted with the Preliminary Plat review, because the property was never platted previously, payment in lieu of parkland dedication is required. Due to an amendment to the City Code, the City's Parkland Dedication policy has been updated to remove areas of undevelopable land from the payment in lieu of parkland dedication calculation. Because of this change, the previous payment requirement of $45,973, which was based on a 14.83 acre area, has been reduced to $43,400 to account for the 0.83 acres of undevelopable wetlands. To summarize, the applicant shall provide payment in lieu of parkland dedication in the amount of $43,400 prior to affixing signatures on the Final Plat.

Private Access Easement:
The proposed plat area is subject to a private Access Easement Agreement with the property owner of the adjacent agricultural field. This access agreement allows said adjacent property owner direct access through the subject property in order to access and farm their adjacent portion of property. CenterPoint Energy states that they are coordinating with the owner of the private easements to ensure continued access is provided between North Riverfront Drive and the property immediately west of CenterPoint’s subject property. Documented proof of an agreement or of a reasonable continuation of the easement condition, shall be required to be provided by the applicant prior to Planning Commission review.  

Conditional Use Permit:
The requested Conditional Use Permit contains two interconnected components, the solar panel array and the hydrogen power facility. 
The applicant states that the proposed project will include a hydrogen power facility that utilizes renewable energy, in the form of an onsite 1 megawatt (MW) solar panel array, to split water into hydrogen and oxygen.

The applicant has provided an Emergency Vehicle Access & Hydrant Coverage plan, which displays the City's largest fire engine circulating throughout the site as well as the coverage distance of each onsite hydrant.

The applicant does not propose any modifications to site access, or parking/loading areas. The applicant states that the proposed project is an unmanned facility, requiring monthly, quarterly, and annual routine maintenance by 1–3 trained personnel. They also assert that any construction-related disruptions will be minor and temporary.

Hydrogen Facility:
The proposed hydrogen production and storage facility will be installed within the existing gravel area located east of the existing onsite propane tanks. The proposed 2,208 square foot (24'x92') building largely reflects the existing structures on the subject property, with proposed exterior metal siding and a standing seam metal roof. Provided floor plans show a large open area for plant equipment as well as a small office space and a restroom. Additional hydrogen plant process equipment is shown to be installed north and east of the proposed building. An outdoor aggregate containment structure is also noted with the proposal. 

The hydrogen facility will consist of the electrolyzer, balance of plant, water treatment system, blending infrastructure, and compression and storage systems. The hydrogen facility is an unmanned facility that will operate continuously, except during occasional periods of scheduled maintenance. The facility will be monitored remotely 24/7 by trained staff at CenterPoint Energy’s Gas Control Center in Minneapolis.

Major components of the hydrogen facility include: RODI skid, water and oxygen separation skid, electrolyzer stack, power supply and rectifier skid, cooling systems, hydrogen handling and compression equipment, PLC control system, power distribution equipment, backup generator, Hydrogen gas compressor, and mobile hydrogen storage. The mobile hydrogen storage unit will have a maximum storage capacity of 146 kg of hydrogen at 6500 psi and is designed to be towed by commercial transport. 

The proposed building for the hydrogen facility will require both water and sanitary municipal services. During normal continuous operation, the hydrogen facility is expected to consume approximately 2 gallons of water per minute (2,880 gallons/day or 86,400 gallons/month). The water treatment skid will discharge approximately 1 gallon of wastewater per minute, while the remaining gallon is consumed in the production of hydrogen (1,440 gallons/day or 43,200 gallons/month). For context, the proposed water usage is similar to other heavy industrial uses within Mankato and Mankato's Water Treatment plant is designed to treat up to 12 million gallons of water per day.* 

All outside mechanical equipment associated with the hydrogen power facility will be sufficiently screened from the Public ROW by fencing. 

The applicant states that the proposed hydrogen plant will be operated and maintained in a similar way to a comparable hydrogen blending facility operational in Minneapolis since 2022. 

The applicant has provided a Photometric Plan for the proposed exterior safety lighting associated with the hydrogen facility. 

Solar Array:
The solar panel array will consist of approximately 2,120 individual 590W panels on roughly 3.2 acres of land west of the current CenterPoint Energy facility at 2400 N. Riverfront Drive. Panels are proposed to sit approximately 8 feet above grade (at their highest point) and will be fixed with a 20-degree tilt to steel racking, which itself will be attached to steel-driven posts embedded into the soil. The panels themselves will be silicon-based with an anti-reflective coating to reduce glare. Aside from the panels themselves, the array will include inverters, switchgear and a transformer. The applicant intends the solar panel array to be accessible through a locked gate near the southwestern corner of the property. The proposed cover plantings (ground cover) inside the solar array footprint will consist of a combination of low-growth natives and a pollinator-friendly seed mix. Maintenance of the site vegetation will be managed by a qualified third-party vendor that will ensure pollinator-friendly vegetation is maintained, and noxious weeds are removed. 

The applicant proposes to erect a 7-foot-tall chain-link perimeter fence around the solar panel array in order to restrict access to the facility. 

The onsite solar panel array is expected to operate on the property in the interim for a 25-year term. The applicant states that they are currently coordinating with Xcel Energy, regarding how the solar array will interact with the local grid when power production exceeds demand from the hydrogen facility.

A decommissioning plan estimate has been provided by the applicant that depicts the assumed costs of decommissioning the solar site if/when it is no longer utilized. The applicant acknowledges that they will be responsible for costs associated with decommissioning the system and restoring the site at the end of its service life / end of use. The solar panel array will be decommissioned, and the site restored to a condition comparable to its pre-conditional condition once the equipment reaches the end of its useful service life, unless a plan is submitted to the City of Mankato to "repower" the facility. A financial surety will be provided to the City of Mankato to ensure decommissioning of the equipment. The hydrogen facility can operate independently of the solar panel array and is not expected to be decommissioned alongside the solar array. 

The applicant intends to screen the solar facility from public right-of-ways by planting six Blue Spruce along the southern property boundary. The applicant had attested that the existing berm area for the rail line provides screening of the panel and that excessive screening may reduce the effectiveness of the solar array. The applicant does not intend to remove any trees or existing vegetative screening with the proposed project. 

Glare Study:
The applicant has provided a Glare Study for all proposed site improvements. Said Glare Study noted that the proposed solar array would create (9) locations for potential glare (see page 1 & 2). Specifically, "glare with potential for temporary after-image", also known as "flash blindness". The aforementioned Glare Study depicts both areas of potential green and yellow glare (defined on page 53). On behalf of the applicant, Muska Electric notes that yellow glare is of higher concern. Following comment from previous Site Plan Review, the applicant has provided an updated narrative from Muska Electric that adds additional clarification. The applicant states that the glare study analysis excludes the screening benefits provided by any newly planted trees or by the rail spur and its earthen berm. It is their belief that these site features would provide additional screening of the panels from the Highway 14 right-of-way. 

The applicant has attested that they are coordinating with MnDOT Staff, specifically Rylan Juran of the Office of Aetonautics, and Scott Thompson, the District 7 Traffic Engineer. The applicant shall ensure that any conditions conveyed by MnDOT shall be met prior to building permit submittal. 

Noise Assessment:
The applicant has provided a pre-construction noise study/assessment of the proposed project. The applicant states that operational project noise levels were shown to be less than 50 dBA at the nearest residential and recreational property lines for both daytime and nighttime hours, which the applicant indicates achieves the MPCA limits noise levels for residential locations to 50 dBA or less during nighttime hours per (Minn. R. 7030.0040).