Energy Transition in Rural America (Spring 2022) - Ramsey Renewable Station, Connexus Energy
By: Sarah Komoroski and Will Hagen
On April 19th, the elusive spring sun came out to shine and our Energy Transition in Rural America class went to visit an innovative renewable energy site: Connexus’ solar-plus-storage facility in Ramsey, Minnesota. Connexus is Minnesota’s largest electric cooperative, serving approximately 960 square miles and over 320,000 people (141,000 meters) in portions of Anoka, Chisago, Hennepin, Isanti, Ramsey, Sherburne, Mille Lacs, and Washington counties. The mission of the co-op is to “[serve] our membership by providing cost-competitive, reliable electricity and related services, with an environmental commitment, affirming the value of member cooperative ownership.” This solar-plus-storage facility, named Ramsey Renewable Station, clearly helps them fulfill this mission. When we arrived, we were immediately greeted by our hosts, Rob Davis and Cory Hetchler, who gifted us packets of honey harvested from bees that feast on the site’s signature pollinator-friendly vegetation. Rob is the communications lead, and Cory is a commercial account representative at Connexus. Rob unlocked the gate, and our tour began.
Connexus is one of the first utilities in the nation to install a solar-plus-storage facility like this. The Ramsey Renewable Station provides 3.4 megawatts of renewable energy and 6 megawatts of storage in the form of lithium-ion batteries. One noticeable feature of the array is that the bottom of the panels sit approximately 1 meter above the ground. This was designed intentionally in order to establish and maintain pollinator friendly vegetation underneath the panels and to help ensure drifting snow doesn’t impede energy generation. The vegetation is managed by Prairie Restorations, a team that’s dedicated to designing, restoring, and managing native prairie plant communities. So, as the solar panels harvest renewable energy from the sun in the form of electricity, the vegetation underneath and around it harvests the same energy to feed an array of critters including Minnesota’s native pollinators and honeybees managed by Bare Honey.
This innovative multi-use land has an array of benefits. At the time of our visit in early spring, we could only witness the remains of last year’s flowers and grasses, but even those provide excellent nesting and overwintering habitat for beneficial insects. Also, compared to typical grasses beneath panels that need frequent mowing with highly polluting equipment, the vegetation at this site only requires one annual mowing, saving members money through reduced maintenance costs.
Neighbors enjoy the plantings too. According to Rob, there was early skepticism about the development from a neighboring farm and RV park, but the inclusion of pollinator friendly vegetation aligns so well with community values that it helped Connexus earn support from the planning commission and city council. The day we visited, we could even see and hear construction of a new housing development nearby.
As we walked through the rows of panels, we noticed uneven parts of the ground. These uneven parts were actually berms created to help slow the flow of stormwater that might otherwise erode the land. The University of Minnesota in partnership with National Renewable Energy Lab and Great Plains Institute are studying this site and four others to develop hydrological models for solar farms help avoid having to construct stormwater collection basins and instead invest resources is deep-rooted ground cover. Soil moisture sensors are installed under the panels, on the drip edge of the panels, and mid row in order to collect data that may be used to inform future solar developments.
After walking up and down the rows of panels, we reached the gem of the tour: the large-scale, on-site battery storage. Between the Ramsey site and a sister site in Athens Township, Connexus has 15 megawatts of battery storage available. The battery storage is an interconnected series of lithium ion batteries that are connected to the grid and can be drawn upon when needed. This project is crucial to Connexus’s transition towards an increased renewable energy profile. Currently, the battery project is owned by NextEra Energy Resources, and Connexus has a contract with NextEra that allows Connexus to draw power from the batteries during peak times when costs are highest. There is a limit to how many times the batteries can be used each month which is specified in the terms of the deal.
This project is a response to two main factors that Rob and Cory mentioned: reliability and cost. With solar generation, the highest energy production can be during low demand periods, and energy production wanes during peak usage. The price of energy corresponds to the demand, so when power is in high demand, prices increase. The battery systems help store the power produced from the solar arrays to be utilized when energy prices are highest during peak times when solar generation is low. By giving Connexus an alternative to buying expensive power during peak usage, they are able to manage their load while maintaining low power costs for its members. Rob was proud to share that Connexus has not increased their rate in the past 5 years, and this project is a major reason why.
Looking forward, Rob mentioned that the future of storage, much like generation, is with a distributed model. Generation is optimized when it is co-located with storage. With rooftop solar increasing in the Connexus service area, so will distributed storage i.e., batteries in homes and cars. Residential batteries may allow Connexus to store power during low usage periods when the price of power is cheap and draw on them during the expensive peaks.
Rob went on to discuss a little more about Connexus’s future. In the 2022 annual meeting, the CEO Greg Ridderbusch shared an update on Connexus’s decision to end their membership with Great River Energy and pursue a transition to a customer relationship instead. This decision was based on what is best for the members, Rob shared. It is clear that the values of rates, reliability, and renewables, all factored into the decision. The current agreement with Great River Energy included a carve out of only 5% self-supply for Connexus with the rest of the power needing to be purchased from GRE. Connexus cites pursuit of greater flexibility and competitive wholesale power prices as drivers of the change. This process will take time, and Connexus will continue to buy power from GRE, but will no longer have the 5% self-supply limit. Rob stated that this switch will allow Connexus to continue to provide reliable, low-cost power to members into the future.
As we wrapped up our tour, Rob shared with us a bit of Connexus trivia that suggested their aims. The Connexus service area currently has the potential for 1.7 million megawatts of solar energy most days (700 watts per square meter times 960 square miles). While they may capture 3.4 megawatts at this site currently, Connexus seems primed to make the most they can out of every drop of sunshine, all in service of providing low rate, reliable power for its members.
A cold early spring day at the Ramsey Renewable Station.