Frequently Asked Questions

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Nature Energy began operations in 1979 in Denmark as a municipal natural gas distribution company supplying gas to local households. Around the same time, Denmark recognized that dairy and hog farms were affecting local water resources. The Danish government started a program to encourage the development of large community digester projects to produce biogas from dairy and hog manure as well as food processing waste and food waste. Through this process, Nature Energy and other Danish companies developed the most efficient biogas production technologies available. Nature Energy established its first community biogas facility in 2015 and went on to expand operations from 30 to over 400 employees, and currently has 14 facilities either under construction or in operations across Denmark, France, and the Netherlands. Nature Energy is now Denmark's largest producer of biogas.

Over the past 20 years, biogas digesters have been built on dairy farms throughout Wisconsin and elsewhere. However, the digester technology in the U.S. has seen very little improvement during that time. St. Croix County, Wisconsin farmers have the opportunity to partner with Nature Energy who has developed the most efficient biogas production technologies available. Using the same safe and efficient process that’s proven successful in Denmark, the Roberts, Wisconsin facility will be one of the first Nature Energy plants in the U.S.

Roberts is an ideal location for several reasons, including access to good workers, reliable infrastructure, and a sufficient number of farms within about 20 miles of the plant. Those farms are needed as a source of dairy manure, turkey litter, and food processing waste that will feed the plant and who are able to receive the plant’s nutrient(s) output after biogas has been produced. Nature Energy worked to identify a location that would support the local sourcing of raw materials and identified suitable land on 130th Street north of the Union Pacific railroad and south of Roberts Business Park. Nature Energy also considered the proximity of the plant to the nearest natural gas interstate pipeline that would be able to receive this new supply of renewable natural gas.

Biogas is produced by the conversion of organic waste products (manure) into a beneficial product (renewable energy) and is considered a renewable resource because it is made from a constant supply of renewable waste streams. Biogas-based natural gas (methane) has the same physical and heating characteristics as the fossil-fuel-based natural gas (also methane) people have used as an energy source for years. Both types of natural gas can be delivered through existing interstate and local natural gas pipeline systems, meaning the biogas from the new Roberts plant will be added to supplies already used in Roberts and surrounding villages. The biogas that will be generated at the Roberts plant will be injected into the regional national gas transmission system, using its infrastructure to deliver a low carbon gas alternative to end users.

  • Help local participating farmers by providing a game changing manure management solution:
    • Producing a form of manure (digestate) that farmers can apply onto crops during the growing season, when the crops can actually use the nutrients.
    • Digestate has a lower application rate equaling less risk of leaching into groundwater, less soil compaction and less fossil fuels used when fertilizing crops.
    • The anaerobic digestion process kills pathogens and weed seeds.
    • Lowering emissions - reducing the methane pollution from unprocessed manure reduces greenhouse gases released into the atmosphere.
  • Nature Energy is negotiating an annual "Payment in Lieu of Taxes" (PILOT) for the project.
  • Other long-term economic gains to local commercial and business owners and operations.
  • The Roberts' facility is Nature Energy's first investment in North America, allowing Roberts to gain notoriety and host visitors to the facility in Roberts to gain firsthand knowledge of this innovative technology.
  • Nature Energy has a reputation of being an outstanding corporate citizen who supports local communities where they operate facilities.

Yes. The Nature Energy Roberts facility requires approximately 12 to 16 full-time employees or subcontractors (or 24,000 to 32,000 manhours per year) to manage facility operations, including managers, operators and truck drivers. Nature Energy will contract with an existing trucking company to run Nature Energy’s specifically designed trucks to haul materials to and from the facility. Local support services such as supplies and maintenance will also be needed for facility operation, including 65 to 75 full-time indirect positions (130,000 to 150,000 manhours per year) and the construction process will require numerous new construction jobs (approximately 650,000 manhours).

The raw organic waste material is gathered from local farms and transported to the Roberts plant where it is placed into digesters, which are large and self-contained processing tanks. Conditions in the tanks are safely and carefully maintained at optimal levels for naturally occurring bacteria to break down the manure and other raw wastes into raw biogas, digestate, nutrient water, and phosphorous-rich solids which are valuable to local agriculture. The raw biogas is upgraded into nearly pure renewable natural gas, which is virtually identical to the gas that comes out of your stove.

The breakdown process takes about 30 to 60 days from the time materials are received until the biogas and other products are produced. In comparison, that process can take up to one year to occur on a farm field, but without the benefit of capturing the biogas.

As the biogas is produced at the plant, it will be transported by a connecting pipeline to the local Northern Natural Gas system at their Town Border Station on the south side of Hammond, Wisconsin. The other products will be transported back to participating local farms for use as fertilizer and soil amendments.

The Roberts plant is proposed for continuous monitoring and operations 24 hours a day, 7 days a week, and will process approximately 730,000 tons of raw waste material per year. This includes dairy manure from 5,500 to 6,500 cows within a 20-mile radius from the plant. Raw material inputs will also include turkey litter and food processing solids from the Jennie O turkey production facility in western Wisconsin. Nature Energy is committed to working with local dairy farms that have 60 or more cows all located within a 20-mile radius of the Roberts location on 130th Street. By working with local farmers of all sizes, we believe Nature Energy’s facility will not influence the growth of existing large dairy production.

The production of biogas is a clean process in a self-contained facility that transforms smelly, hard-to-handle manure and other wastes into renewable natural gas and other products that are useful back on the farms from which the waste was collected. As proven in nearly a dozen successful plants in Denmark, Nature Energy is committed to actively managing the occurrence of nuisance odors, noise, light, and truck traffic from the plant. We’ve developed several engineering controls and reliable best practices that will help make the new plant serve as a good neighbor in the community.

Odor: We all know manure and animal waste is stinky, but the trucks and equipment involved in the Nature Energy plant are specifically designed to keep the materials enclosed during processing and transport in clean, well-maintained trucks to and from the plant. Inside the plant, waste materials will be managed indoors in structures that have negative pressure applied, meaning fresh air is brought in and is treated through special bio filters before it is released. Also, inside the state-of-the-art facility, we’ll continuously monitor conditions and maintain air quality equipment and controls. At the end of the process, the material has significantly less odor than untreated manure and landfills.

Noise and Visual: The increase in truck traffic to and from the plant may produce some additional noise, but we want to be respectful of our neighbors and all the folks that use 130th Street and other local roads. The new plant will be located adjacent to an existing railroad which has intermittent noise levels. Nature Energy studied noise levels at nearby sensitive receptors and found that residences in the vicinity of the facility experienced noise levels similar to a busy residential road. Most homes in Roberts will be more than 1,000 feet from the plant, which will greatly reduce the amount of light and noise seen and heard from the plant. Additionally, Nature Energy will plant trees along the boundary of the facility to further address noise and visual concerns.

Traffic: Trucks will move to and from the plant during normal operating hours Monday through Friday from 6:00 a.m. to 8:00 p.m. and Saturdays from 6 a.m. to 3 p.m. Delivery of raw material to the plant and transport of digestate manure and other products from the plant will account for about 90 to 95 trucks per full working day and approximately 45 trucks on Saturdays. Nature Energy has completed a traffic study to identify potential traffic impacts from the new plant and what improvements to 130th Street will be needed, such as designated turn lanes and safety signage. The dairy manure haul trucks will be fully self-contained vessels similar to the tanker trucks that haul milk. The turkey litter haul trucks will be the same covered trucks that local processors have been using for many years. All trucks will be kept clean and well maintained, and each truck will be washed after being unloaded at the Nature Energy plant.

Because Roberts is a farming community, water quality impacts from phosphorus and nitrates are always a concern. The products from the Nature Energy process at the Roberts plant will provide key nutrients such as nitrogen, phosphorus, and potassium in a form that allows better uptake by crops. This is an important benefit and improvement over raw manure that is currently being applied. Nature Energy will provide dairy and crop farmers with the products they need to apply according to their nutrient management plans.

Nature Energy uses an advanced record-keeping system to track the biomass inputs received from farmers and the digestate, nutrient water, and fiber fraction delivered to participating farms. This system also tracks the specific nutrient contents of the incoming and outgoing material. This record-keeping system ensures that farmers get the necessary nutrients for their operations. Nature Energy will only contract with farms with Nutrient Management Plans in place. Farmers will be responsible for the safe handling of the manure prior to pick up of the material and storage of the digestate after Nature Energy delivers back to the farmers. All Wisconsin farms, regardless of size, must comply with Wisconsin’s agricultural standards and prohibitions, which govern headland stacking. Only Generally Recognized As Safe polymers will be used, if any are required.

We believe the new plant is a net benefit to the Roberts community and surrounding area. Property values of adjacent properties and the rural character of the neighborhood within and near the Industrial Rail Park District are not anticipated to be impacted by the proposed project. Properties to the north are of a similar industrial nature as the proposed site activities. Adjacent properties to the northwest are zoned Multiple-Family Residential Park and Recreation; however, the western half of the property for the proposed facility would be vacant and provide a buffer between sites activities and these properties. The adjacent property to the southwest is currently vacant and contains a waterbody. A 2019 study of impact on real estate values in Pleasant Valley showed that a similar biogas plant would have an "overall minimal to negligible impact for properties within a 1-mile radius." The detailed analysis showed a potential small impact of 1 to 2 percent on properties within 0.5 to 1 mile of the biogas facility, but the authors noted that estimate as a "worse-case" and showed how actual impacts are expected to be negligible.

Nature Energy and our local partners and consultants are working through the local permitting process with the Village of Roberts. In addition to the local approvals, Nature Energy will obtain all applicable federal and state permits that will be required for the construction and operation of the plant. The permitting process is expected to be complete near the end of summer with construction set to begin in Fall/Winter 2022. Once construction begins, it is expected to take approximately 18 months to complete.

Click for renderings of how the Roberts plant will look after construction. Just like our successful operations in Denmark, the new plant in Roberts will feature state-of-the-art technology to generate biogas in clean and safe facility. We want to be good neighbors in the new location, including use of trees around the property to reduce noise and visual impacts, and the trucks transporting materials to and from local farms will be kept clean and in good condition.

The project will support the health, safety and welfare of the community through the development of biogas as a renewable energy source and other outputs that provide numerous environmental benefits. The new plant will also provide economic benefits through the creation of direct and indirect job opportunities, use of local services and supplies, and payment in lieu of taxes.