What is solar energy used for?
Once converted into electricity, solar energy is used in homes and businesses just like any other form of electricity.
What are some advantages of solar energy?
After the initial investment in solar-energy equipment, the costs are minimal since the sun provides free "fuel." These facilities are not affected by the supply and demand of fuel or subject to price volatility, and solar energy can help reduce America’s dependence on foreign sources of energy. Solar energy is also clean and renewable, which helps protect our environment.
How does Solar Energy Work?

1. As light hits the solar panels, the solar energy is converted into direct current (DC) electricity.
2. The direct current flows from the panels into power inverters and is converted into altering current (AC) electricity, which is suitable for use by homes and businesses.
3. The AC electricity from the power inverters is collected using cables and delivered to a central electrical substation, where it passes through a power transformer.
4. The electricity travels through transformers, and the voltage is boosted for delivery onto the transmission lines.
5. Clean, renewable, American-made solar electricity is delivered to homes and businesses.
How many solar facilities does your company have and where are they located?
Through its subsidiaries, NextEra Energy Resources is the world’s largest generator of renewable energy from the wind and the sun. We currently have ownership interests in approximately 3,400 MW of operating solar projects (as of Dec. 31, 2021), representing universal-scale solar facilities in 29 states, as well as multiple small-scale (distributed generation) solar projects.
How did your company choose this location for the Duane Arnold Solar project?
We carefully select sites for potential solar project development based on a number of factors, including: (i) suitability for solar generation; (ii) interest of participating landowners; (iii) proximity to existing infrastructure; (iv) existing transmission and injection capacity; (v) constructability; (vi) environmental factors; and (vii) suitability with cultural and historic resources. With respect to generation suitability, Duane Arnold Solar concluded that the site was suitable for solar development based on a review of nearly 25 years of weather and satellite data.
Who is the client for this energy?
Duane Arnold Solar will develop, design, permit, and construct Phases I and II of the Project. Alliant Energy, through its subsidiary Interstate Power & Light Company (IPL), will purchase the project and distribute the renewable energy to its customers, including Iowa residents.
Will eminent domain be used in any of the phases?
No. The Project will be located 100% on voluntary easements/permits. As such, Duane Arnold Solar will not seek the use of eminent domain.
How much are landowners being paid?
Landowners who choose to participate in the Duane Arnold Solar Project receive payments that can help them enhance and diversify their incomes. Agreements with participating landowners include an (1) Option Agreement - to hold a solar easement area for a defined period of time; and (2) a Solar Lease and Easement Agreement. Participating landowners are paid for the option agreement through an annual payment. The option agreement can be converted to a Solar Lease and Easement Agreement. Under the Solar Lease and Easement Agreement, the participating landowner is paid per utilized acre per year. The specific payment terms with participating landowners are confidential.
How long are the lease agreements?
The term of the Option Agreement is typically 5 years. The term of the Solar Lease and Easement Agreement is 30 years with a potential 10-year extension.
Who has the authority to approve this Project at the state and local levels?
The siting of the Project will be subject to approval by the Iowa Utilities Board (“IUB”) and the Linn County Board of Supervisors.
Will the Linn County Board of Supervisors be asked to change the local land use ordinance as part of their decision to grant the permit for Duane Arnold Solar?
Because the Project falls within the definition of a Utility Scale Solar Installation set forth in the Linn County Ordinances, the Project must be located in a Renewable Energy Overlay District (“Overlay District”). This requirement was created by ordinance passed in December of 2020.1 Duane Arnold will be required to go through the rezoning process in order to have the County create the Overlay District that encompasses the Project parcels and approve the Project for development.
How does this project help Iowa meet its energy? Why use farmland for a solar project?
In the aggregate, Iowa produces enough energy to meet the equivalent of its energy needs, but it does not produce enough to meet those needs during every hour of every day.
Moreover, location on farmland is one factor considered in determining whether and where to locate renewable energy facilities. The Project has a limited impact on cropland acreage in Iowa. For example, the Project Site of Phase I of the Project consists of approximately 316 acres, roughly 90 percent of which is currently being used to farm various types of row crops. Similarly, Phase II of the Project will be located on approximately 816 acres. Collectively, this represents only 0.002% of Iowa’s 26 million acres of cropland. Agricultural production on these properties will be suspended for the life of the Project. Similarly, the Project site is less than one percent of Linn County’s 324,500 acres of farmland. However, following Project decommissioning, the Project Site will be available to return to agricultural production.
The Project will not have an adverse impact on agricultural production on the surrounding areas. A vegetative ground cover mix will be planted and maintained throughout the Project Site. This will manage erosion by increasing stormwater infiltration. Stormwater infiltrates soil at a higher rate on vegetative ground cover than on cultivated cropland. As such, the change to perennial vegetation will manage additional runoff resulting from the solar modules and access roads.
Why didn’t NextEra continue to operate Duane Arnold Nuclear Plant?
NextEra Energy Resources, LLC (“NEER”) and its subsidiaries are wholesale providers of power and NEER is the owner and operator of the Duane Arnold nuclear plant. As announced in 2018, the customer for the Duane Arnold nuclear plant – Alliant Energy – decided to terminate its power purchase agreement with the nuclear plant early and replace some of the generation with energy provided by wind investments in Iowa. According to the CEO of Alliant Energy, this decision resulted in significant savings for Alliant’s customers -- nearly $300 million on a net present value basis, over 21 years.2
How will the project minimize environmental impacts?
The Project has been sited and designed to avoid and minimize impacts to environmental resources in the Project area. For example, the Project is designed to avoid impacts to all jurisdictional wetlands and waterbodies. In the event impacts are subsequently identified, any impacts will be permitted in accordance with the United States Army Corps of Engineers (“USACE”) and, if applicable, Iowa Department of Natural Resources (“DNR”), regulations. In addition, the Project has been sited to avoid impacts to forest areas and limit tree clearing activities in the Project area.
Can the Project Site be used for farming in the future?
Yes. When the Project ceases operation, the facilities will be decommissioned and dismantled and the site restored to its pre-construction condition. A decommission plan will be filed with both the IUB and the county.
To facilitate a return to agricultural use following decommissioning, the Project land will be tilled to break the new vegetative growth, which will enhance the topsoil condition. Accordingly, the soil condition on the site will be the same or in better condition than before the Project. Once the Project is fully decommissioned, each property owner can sample the soils and, as needed, add fertilizer to match the crop(s) to be planted. As such, it is very likely the cropland will be returned to pre-construction yields.
How are the solar panels disposed of and who takes care of that?
At the end of the Project’s useful life, the Project owner will assess whether to cease operations and decommission the Project or to replace equipment and attempt to extend the life of the Project. To the extent possible, Project equipment will be reconditioned, resourced, and/or recycled. For example, solar panels typically consist of glass, polymer, aluminum, copper, and semiconductor materials that can be recovered and recycled at the end of their useful life. Any materials that cannot be recycled will be disposed of at approved facilities.
Do the panels have materials that are harmful to the environment?
Modern photovoltaic (PV) solar panels are made of materials typical of those found in electronic equipment and are encased, so as not to pose a concern for the water supply or public health. As stated previously, Solar PV panels typically consist of glass, polymer, aluminum, copper, and semiconductor materials that can be recovered and recycled at the end of their useful life. Crystalline silicon panels, which are being considered for the Project, represent approximately 90 percent of solar panels in use today. Research has shown they do not pose a material risk or toxicity to public health and safety.
Moreover, to provide decades of corrosion-free operation, solar cells are encapsulated from air and moisture between two layers of plastic, with a layer of tempered glass and a polymer sheet or industrial laminate. In the same way a windshield cracks but does not shatter when broken, a damaged solar cell does not generally create small pieces of debris.
Can the panels be replaced?
Yes. We monitor the operations of our solar facilities 24/7. Should any of the panels sustain damage that would impact their safe and efficient operations, our solar technicians will replace them.
How does your company work with neighboring landowners to mitigate the visual impact of the Project?
In response to reasonable requests by participating and non-participating landowners, Duane Arnold Solar will consider screening vegetation or other similar measures on a case-by-case basis. Duane Arnold Solar has discussed potential mitigation measures with participating and adjacent non-participating landowners. These discussions will be on-going through construction and continue thereafter.
What setbacks will be used for the Project?
For Phase I and II of the Project, the fence line setback ranges between 50 feet and 80 feet from non-participating landowner property lines and at least 300 feet from any non-participating landowner dwelling.
Will this Project produce a net savings in fossil fuels emissions?
Yes. Solar energy is one of the most efficient sources of energy generation with respect to limiting carbon dioxide equivalent emissions, as emissions are primarily produced during the manufacture of panels and not during operation. The IUB applications include air emissions analyses comparing the estimated emissions of the Project to equivalent fossil fueled-fired facilities. Phase I is estimated to reduce CO2 emissions by approximately 3.14 million metric tons compared to an equivalent coal-fired facility and 1.355 million metric tons in comparison to a natural gas facility. Phase II is estimated to reduce CO2 emissions by approximately 9.49 million metric tons compared to an equivalent coal-fired facility and 4.1 million metric tons in comparison to a natural gas facility. By design, storage batteries do not create any waste product during their charging and discharging cycles. It is anticipated that the Project will not result in the creation of a significant amount of waste once constructed.
Will this Project only produce energy during the daytime? Does the battery work well with the solar?
A battery energy storage system can help balance the load on the power grid and deliver electricity to customers when it is most needed. Phase II of the Duane Arnold Solar Project is proposed to include 150 MW of solar generation and 75 MW of battery storage, allowing the Project to inject power into the bulk electric grid during both daytime and nighttime hours. Specifically, the solar arrays charge the batteries with excess power not injected into the bulk electric grid. This power is stored by the batteries for later injection into the electric grid during times of lower solar generation (e.g., non-daylight hours). Once fully charged a battery can inject power for 4 hours.
How many jobs (short and long term) will be created by this Project and what’s the impact in taxes (state/local)?
During construction, approximately 100 jobs will be available for each phase of the Project with two to three full-time equivalent jobs once the Project is in operation. Local businesses will experience an increase in revenue because the construction workers will require places to eat, sleep, buy food and gas, and obtain other day-to-day amenities.
Duane Arnold Solar – Phase I is anticipated to contribute up to $1.78 million in property taxes alone for all taxing districts over the life of the Project. Phase II of the Project is expected to contribute up to $5.42 million in property taxes over the life of the Project.
According to an economic impact study conducted by Strategic Economic Research, the two projects will have a combined positive economic impact of up to $260 million on the State of Iowa (including up to $154 million in Linn County). That includes the cumulative ripple effects of new jobs, wages, tax revenue and other economic activity during construction and over the estimated 30-year life of the projects.
Will the construction jobs be hired locally?
Duane Arnold Solar will retain an Engineering, Procurement and Construction (“EPC”) contractor to construct the Project. Typically, it is the EPC contractor that hires workers to construct a proposed project. However, our goal is to hire as many workers as possible from the local areas where we construct our solar projects.
Does your company intend to build utility-scale solar projects in other areas of the state?
NextEra Energy Resources has invested more than two billion dollars in the state of Iowa, including 10 operational wind projects and a repair and training facility. We continue to look for opportunities to invest in good projects that also create economic opportunities for the state and communities that host them.
Will the Project have a negative impact on property values?
No. Based upon Market Impact Analyses conducted for both Phase I and II, the Project will not have a negative impact on either rural residential or agricultural property values in the surrounding area.
Will the Project be built to withstand severe weather?
Duane Arnold Solar will design and construct the Project to withstand various extreme weather events, including high winds, flooding, hail, and accumulating winter precipitation. The Project will meet the site-specific wind load requirements of both the International Building Code (IBC) Section 1609 and the American Society of Civil Engineers (ASCE) 7-10 or 7-16, as applicable. Consistent with applicable requirements, the Project facilities, including the racking system and the tracker supports that attach the PV modules to the racking system, will be designed in accordance with Risk Category I - ASCE 7-10 or 7-16, as applicable. To provide decades of corrosion-free operation, solar cells are encapsulated from air and moisture between two layers of plastic, with a layer of tempered glass and a polymer sheet or industrial laminate. In the same way a windshield cracks but does not shatter when broken, a damaged solar cell does not generally create small pieces of debris.
How will stormwater be controlled at the Project Site during both construction and operation?
The Project will be designed to manage any permanent changes in stormwater runoff resulting from development of the Project and Duane Arnold Solar will be required to obtain authorization under the Iowa Department of Natural Resources (“IDNR”) General Permit to Discharge under an Iowa Pollutant Discharge Elimination System IPEDS Permit (“IDNR Stormwater General Permit”) prior to the commencement of construction. Temporary stormwater best management practices (“BMPs”) will be used during Project construction, and construction will be completed in accordance with the IDNR Stormwater General Permit and project-specific Erosion Control and Storm Water Management Plans. The temporary BMPs minimize potential soil erosion through a combination of erosion and stabilization practices, which minimize causes of erosion and the spread of sediment off-site.
Moreover, the Project Site, including areas beneath and around arrays, will be planted with perennial vegetation. This will manage erosion by increasing stormwater infiltration. Stormwater infiltrates soil at a higher rate on vegetative ground cover than on cultivated cropland. As such, the change to perennial vegetation will manage additional runoff resulting from the solar modules and access roads.
Once constructed, permanent stormwater facilities and perennial vegetation will be managed in accordance with the IDNR stormwater permits applicable to the Project. In contrast to agriculture, the Project will not require regular ground disturbance once the Project is constructed and vegetation is established. Thus, adverse impacts to water quality are unlikely to occur as a result of erosion or stormwater runoff from development and operation of the Project.
Will the Project have an undue adverse impact to wildlife?
No. The Project will work in harmony with the environment. It will not impact recreation on neighboring lands and is designed to minimize any impact to local wildlife. In fact, of all forms of energy generation, solar energy has among the lowest impacts as it emits no air or water pollution, emits little sound and creates no hazardous waste. Moreover, because the arrays will be individually fenced, wildlife connectivity is not anticipated to be unduly impacted.
Will the Project produce significant noise?
No. Sound studies were conducted for both Phase I and II of the Project. The results of the Sound studies demonstrate that sound levels will be typical of a rural environment.
Will the Project require any unique municipal services?
No. The Project will be installed to conform to all applicable electrical and fire codes and will not require any unique fire, police, or rescue services. In addition, the Project operations team will meet with local responders to review the Project configuration and educate local responders about any potential assistance of emergency responders that may be required.
How will the Project be decommissioned?
At the end of the Project’s useful life, the Project owner will assess whether to cease operations and decommission the Project or to replace equipment and attempt to extend the life of the Project. If the decision is made to cease operations and decommission the Project, to the extent possible, project equipment will be reconditioned, resourced, and/or recycled. For example, solar panels typically consist of glass, polymer, aluminum, copper, and semiconductor materials that can be recovered and recycled at the end of their useful life. Any materials that cannot be recycled will be disposed of at approved disposal facilities. A Decommissioning Plan is included as an Exhibit to the Applications. To ensure that funds are available for decommissioning and restoration of the Project, the Project owner will provide security in the form of a surety bond, letter of credit, parent/corporate guarantee, or other financial instrument that is mutually acceptable to the County and the Project Owner.
Iowa Utilities Board Applications
View the full Iowa Utilities Board application for Duane Arnold Solar I.
View the full Iowa Utilities Board application for Duane Arnold Solar 2.
1 Linn County Ordinance Sec, 107-149
2 “NextEra Energy Resources and Alliant Energy agree to shorten the term of the Duane Arnold Energy Center power purchase agreement; Alliant Energy customers to save hundreds of millions of dollars,” July 27, 2018.