Mt. Hood City Corridor serves as a communal gathering venue situated in the Greater Hood River Valley, functioning as a recycling center, community meal distribution site, middle school classroom, and space for special public events. Built initially in 1914 and owned by Hood River County, this facility is recognized as a registered Historic Building. It has previously functioned as an emergency relief center and has supported public health initiatives. Since 1988, the Mount Hood Towne Hall Association has preserved and managed the facility under a long-term lease with the county, ensuring it continues to serve as the community hub for the area.
Due to its geographical characteristics, Hood River County encounters distinct challenges in the resilience of its energy resources and infrastructure. Factors such as wildfires, ice storms, earthquakes, extreme temperatures, and high winds all pose potential risks for power outages affecting local residents and businesses. This issue was highlighted in the 2018 Hood River County Energy Plan, which prioritized energy resilience as a significant concern. The Hood River County Energy Council (HRCEC), charged with implementing the Energy Plan, collaborated with the Hood River County Office of Emergency Management to designate Mt. Hood City Hall as a crucial facility ideally situated and configured to function as a resilience hub for the Greater Hood River Valley.
Fast forward to September 2023. With a specific site in mind and a list of resilience goals established, Hood River County secured a grant from the Oregon Department of Energy’s Community Renewable Energy Grant Program to fully fund a microgrid feasibility analysis for the proposed project.
Introducing: Mayfield Renewables. Our team conducted a load assessment, developed resilience and financial models, aided in equipment selection, and provided a comprehensive feasibility analysis report along with a 30% initial design plan. Mayfield also presented its analysis findings at a public commentary event organized by the project partners, adjusting the initial report based on feedback from the 40-50 community members present.
Project Objectives
The Hood River County Energy Council contacted Mayfield Renewables after acquiring grant funding for the feasibility study in January of 2024. The analysis focused on the Mt. Hood City Hall structure and the surrounding land.
The community initially aimed for the microgrid to provide two weeks of backup power, with a 50% confidence interval; however, when the project team opted against including a fossil-fueled generator in the design, the resilience parameters were reassessed. Mayfield was tasked with presenting several specific visions of what could be achieved, then collaborating with project partners and incorporating feedback from the community to define the most promising direction.
More specifically, Mayfield developed multiple design alternatives and simulated resilience performance for various load scenarios based on user load selection priorities. Feasibility studies typically involve research and active participation, and through this engagement, we clarified technical, functional, and aesthetic limitations.
Project Challenges
Mayfield’s feasibility studies are inherently iterative. Microgrid systems are intricate. Our approach is designed to uncover previously unknown limitations, after which we collaborate with the client to find a viable solution.
The Mt. Hood City Hall microgrid feasibility study provided several examples of both known and unknown constraints, which were assessed with input from the Hood River County Energy Council, the Mount Hood Towne Hall Association Board of Directors, and community members to ensure that the final outcome satisfied all stakeholders.
Grant Support
The feasibility analysis was completely funded by an Oregon Department of Energy grant. HRCEC aimed to utilize the feasibility study to apply for a construction grant of up to $1 million, which set a strict budget limitation.
Mayfield crafted the entire microgrid system around a $1 million budget for procurement and construction. This budget constraint influenced decisions regarding equipment choices, system size, system performance, and aesthetics.
Load Selection
Load selection is a common challenge in the development
of microgrid strategies when only a section of loads will be supported. In this scenario, due to significant seasonal fluctuations in solar generation, it was nearly impossible to provide two weeks of complete backup power during winter solely using PV and battery resources. Mayfield assisted with load selection alongside the project team.
During the initial assessment, Mayfield simulated four load scenarios ranging from the most inclusive (33 loads) to the least (18 loads), and generated a synthetic load profile that illustrated projected electrical consumption patterns across each “scenario.” The information was presented in the dispatch chart shown above. Ultimately, the client opted for the load scenario that they believed offered the best balance between facility operation and resilience during a grid failure.
Insufficient Load Data
A component of the load modeling process mentioned previously involves gathering accurate load data. High-priority backup loads were spread across multiple electrical panels. As a general best practice, Mayfield strongly advises the use of interval data instead of representative load profiles.
Mayfield conducted a load assessment by installing a metering device to capture interval data from one electrical load panel in the facility that housed most of the loads the Town Hall aimed to support, including a major heating unit. Fortunately, the load assessment took place during a winter storm, which was one scenario the microgrid was intended to handle.
Historic Building Designation
Erected over a century ago, the Mt. Hood Town Hall is a designated Historic Building, categorizing it under a distinct (and much more stringent) permitting classification aimed at preserving the building’s historical charm. This meant Mayfield could not default to maximizing the available roof space for a PV array. Instead, the entire system had to be designed to balance functionality and visual appeal.
Mayfield collected site information from the Mount Hood Town Hall Association (MHTHA) and carried out an on-site visit to identify suitable locations for new microgrid equipment. Various PV canopy options (for instance, a custom-built wooden-framed solar canopy versus pre-engineered metal purlins) were assessed with MHTHA and the local AHJ to select an aesthetically pleasing yet permissible design.
Outcomes
The entire feasibility study took approximately four months to complete. Mayfield’s deliverables encompassed a feasibility report featuring a system description, modeling inputs and assumptions, equipment specifications, and other critical project details, including a 30% preliminary plan set.
Hood River County submitted the report and plan set as part of their construction grant application, which was subsequently approved for the maximum amount of $967,000. Grant providers are typically cautious. Mt. Hood Town Hall project partners attribute the insights gained from the comprehensive feasibility study report as one of the key factors in winning the competitive grant. As of this writing, construction is anticipated to commence in the fall of 2025.
Mayfield Renewables is an engineering consultancy specializing in commercial and industrial PV and microgrid engineering. Contact us today for a consultation.
