Beth Israel Congregation
Energy Upgrades
Client
Beth Israel Congregation
Year
2023
Location
Ann Arbor, MI
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Most of the mechanical equipment and the roofing in Beth Israel Congregation’s Synagogue are reaching the end of their useful life. BIC’s leadership wanted to anticipate these projects and evaluate sustainable replacement options. Inclination Engineering led a team of design professionals and contractors to create a schematic design to replace the roof, older mechanical equipment, and kitchen appliances. A baseline option with replacement gas-fired models was compared against a sustainable alternative with electrified heat pump replacements and rooftop solar panels. The project identified existing deficiencies in the building systems and suggested solutions to implement during replacement. The schematic design is the first milestone in the design process. It is an opportunity for BIC to provide feedback to the design team and to choose between the two mechanical equipment replacement options.
Roof Replacement and Solar
The schematic design narrative recommends replacing the synagogue's roof in the next 3 years, after the rooftop mechanical equipment. The new roof will have an added layer of insulation to meet current energy code requirements. After the roof is replaced, a 41.7 kW rooftop solar array would be installed over most of the Synagogue roof. The array would produce an estimated 49.8 MWh of electricity, saving $7,000 during its first year and contributing a net cash flow of $174,000 over 25 years based on expected energy price increases.
Kitchen Appliances
Electric kitchen cooking appliances were evaluated, however the building’s electrical service did not have enough capacity to make this replacement practical. Instead similar gas replacement unit will be provided.
Mechanical Systems
The mechanical equipment to be replaced in the Energy Upgrades Project includes the three rooftop units serving the upper-level worship spaces, the kitchen rooftop unit and exhaust fan, and two of the four basement furnaces. Two options were prepared. A baseline option with gas-fired replacement units and a sustainable alternative with heat pumps units.
Both mechanical equipment replacement designs will correct existing deficiencies with solutions such as:
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Improving greasy fume capture in the kitchen with a properly sized makeup air unit and low speed makeup air diffusers.
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Reducing the humidity and heat in the kitchen with an exhaust hood over the dishwasher.
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Controlling the temperature of the library and lobby independent of the small social hall by adding an additional rooftop unit.
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Providing code required ventilation to the basement classrooms with a dedicated outside air system. This system will also dehumidify the basement.
The electrified option selected uses a combination of air source and ground source (geothermal) heat pumps to economically provide reliable comfort. Ground source units will provide reliable heat to exterior areas in even the coldest temperatures. Air source units will handle the large ventilation and cooling loads of the worship spaces when they are occupied.
Costs
The gas-fired baseline cost was compared against the electrified alternative, with heat pump units and solar generation. This included deducting the expanded 30% tax incentives for energy generation and storage. The combined energy efficiency and solar generation gave a simple payback to the sustainable upgrade option of 20 years. We hope to shorten the payback time through the application of additional grants and tax incentives as the project design continues.