In 2009, when the City of Saint Paul received a substantial Energy Efficiency and Conservation Block Grant (EECBG) from the U.S. Department of Energy, city leaders wanted to implement high-profile projects that demonstrated the potential for energy efficiency and renewable energy across the state of Minnesota.
As part of the American Recovery and Reinvestment Act (ARRA), the EECBG program was designed to help local units of government create or retain jobs, reduce greenhouse gas emissions, and reduce energy use. Saint Paul was able to use this funding on a variety of energy efficiency projects in its municipal buildings, but one project was unique, in that it served as a model for a particular type of building owned by public and private organizations across the state: parking ramps.
In one of Saint Paul’s most successful and visible projects supported by EECBG funding, the city worked with the Saint Paul RiverCentre to bring a range of exciting improvements to its parking ramp. The first of these improvements included converting 1,087 high pressure sodium lights to new, energy-efficient fluorescent lamps. The project was an ambitious undertaking, costing the city nearly $126,000. However, the RiverCentre received over $44,000 in EECBG and an additional $73,000 in rebates from the city’s electricity provider, Xcel Energy. In the end, the retrofit was tremendously successful. It reduced the parking ramp’s energy demand by 47%, adding up to more than $50,000 per year in savings, paying back its capitol costs in under 3 months. In addition to cost savings from reduced energy usage, the new light bulbs last longer before needing replacement, decreasing money and time spent on maintenance. The lighting has also increased visibility at the ramp, creating a safer environment for the RiverCentre’s patrons.
The city also used EECBG funds to install two electric vehicle charging stations on the roof of the parking ramp. These two stations join nearly 20 other charging stations installed throughout the city as part of a separate initiative. That other initiative, in which the city worked in collaboration with Drive Electric Minnesota—a partnership of local and state governments, Xcel Energy, local businesses, and non-profits—was also supported with EECBG funding. All of these installations are part of Saint Paul’s larger efforts to bring electric vehicles and plug-in charging infrastructure to Minnesota. By installing charging stations in highly visible locations frequented by many visitors, such as the RiverCentre, the city hopes to spark visitors’ curiosity, let consumers know that charging infrastructure is available, and hopefully increase demand for electric vehicles.
Whether or not they own electric vehicles, drivers visiting the RiverCentre may take note of another one of Saint Paul’s efforts to make its transportation infrastructure more sustainable and environmentally friendly. Utilizing nearly $400,000 in EECBG funding, the city replaced 1,500 50W and 70W high pressure sodium (HPS) globe-style street lamps with 29W LED lights in the downtown area. The new LED replacements cause much less light pollution than HPS bulbs, and they have a much longer working life, burning out less frequently and keeping streets lit more consistently. In addition to increased lighting for safety, this saves the city money on the costs of maintenance and replacing bulbs. LED fixtures also use significantly less energy and emit less heat, so the city is realizing significant energy and cost savings.
Perhaps the most exciting project to be unveiled at the RiverCentre parking ramp, however, is a massive solar array installed on the south wall of the ramp, facing the river. This 82kW solar electric photovoltaic (PV) system, installed by Hunt Electric, consists of 348 panels and is expected to generate about 100,000kW annually for the RiverCentre. Westwood Professional Services, the company that designed the installation, faced a monumental task. Most solar arrays are installed on flat or slanted surfaces, but the RiverCentre installation needed to be built on a wall completely perpendicular to the ground. This offered unique challenges such as dealing with shading from neighboring buildings and protecting the panels from vandalism and theft. However, the most difficult task was supporting the weight of the panels. This was accomplished by designing a massive steel frame, which took a significant amount of time to install, but ultimately proved successful.
The solar PV project was supported by ARRA funding that was similar to EECBG. Saint Paul and Minneapolis received $3 million in ARRA funds to support their Solar American Cities program, a partnership designed to decrease barriers and promote solar production in the Twin Cities. Saint Paul used the funds it received to secure 220kW of solar photovoltaic (PV) at six facilities, including the RiverCentre parking garage, the Rondo Library, and the Western District Police Station. All the installations were fully integrated with the electrical grid, and the city was able to leverage approximately $400,000 in rebates through Xcel Energy’s Solar*Rewards and Minnesota-made Bonus programs.
The RiverCentre supported the projects at its parking ramp as part of their “80-20 in 3” initiative, a goal to reduce the operational carbon footprint of the facilities by 80% and increase the buildings’ efficiency to 20% better than average over three years. The RiverCentre parking garage was targeted by Saint Paul and Xcel Energy partly because it is located in the Energy Innovation Corridor, which is an area along the planned Central Corridor Light Rail Transit line. The Energy Innovation Corridor highlights projects related to energy efficiency, renewable energy, transportation and smart technology.
The RiverCentre parking ramp is now a highlight on the Energy Innovation Corridor, and has been a big step toward the RiverCentre’s “80-20 in 3” initiative. Most importantly, though, the RiverCentre parking ramp now serves as a model for other ramp owners—both public and private—who are considering energy efficiency projects to lower their own energy costs and decrease their environmental impact. In fact, prior to the work at the RiverCentre, ramp managers were skeptical that they could make these types of projects cost-effective. However, since the energy efficiency work at the RiverCentre, both private ramp managers and other cities have been contacting the city of Saint Paul to learn more about how they can replicate the success at the RiverCentre parking ramp.
- : City of Saint Paul, Ramsey County
- : Energy efficiency
- : $126,000
- : EECBG – $44,000; Xcel Energy rebates – $73,000; other funding – $9,000
- : Lighting retrofit – 6,973,289 kWh saved; Reduced parking ramp’s energy use by 47%; Reduced RiverCentre’s energy costs by $50,000/year
- : Improved visibility and safety in the RiverCentre parking ramp; Serves as a community model for energy efficiency at a parking garage.
Title Image Credit: The RiverCentre parking ramp now serves as a model for other ramp owners—both public and private—who are considering energy efficiency projects to lower their own energy costs and decrease their environmental impact.