Figure 2 : Operational Carbon Analysis a back-up gas-fired system the university was much more accustomed to maintaining and operating . It also gave some resiliency to the system , making it not reliant solely on the electrical grid . The hybrid approach gave the university a satisfactory solution to significantly reduce their carbon emissions by operating the HRC for a majority of hours of operation , while significantly improving their ROI compared to an all-electric plant . Moving forward , we will need to evaluate the impact of having decentralized electrified HHW plants in a campus setting with a central CHW , with a likely outcome being a move to a more centralized electrified plant with HHW and CHW storage .
As designers , we need to consider the impact of pursuing electrification for heating systems and be equipped to guide owners to make an informed decision on implementing these systems on a large scale at their campuses and buildings .
These electrical upgrade costs have not been factored into Table 3 and would further impact the return on investment ( ROI ) on such a project . Option 3 is the only viable option of those presented here , without requiring an upgrade to the electrical infrastructure . To confirm Option 3 was viable , a meter read of the facility was performed , which determined the actual load ( plus a 25 % safety factor ) was 343A of the total available 800A .
One of the project ’ s main KPIs was to understand the carbon impacts of the proposed system . Option 1 is an improvement from the base case ; however , the COP of 2.12 for an airsource heat pump does not give the desired impact compared to a gas-fired boiler with a peak efficiency of 96 % at a fraction of the cost for the equipment . Option 2 is the most desirable from an operational carbon perspective , but is still limited based on first costs and impacts to the existing building ’ s electrical infrastructure . Option 3 , the hybrid plant , provides a viable option to electrify the existing HHW system with minimal impacts to the existing building infrastructure . Options 1 and 2 could be achievable but would require HHW thermal storage to downsize the heat pumps to avoid an upgrade to the electrical infrastructure or would require an upgrade to the electrical service .
Many factors came into consideration to finally determine a hybrid plant was the most viable solution to move toward electrification . This campus has over 110 facilities , and the stakeholders were looking to introduce heat pump technology as a pilot project to determine the feasibility of introducing the technology throughout the campus . The hybrid plant offered them the opportunity to introduce the newer technology to the campus while also providing
References
1 . Del Monaco , J . 2022 . “ Adopting and Implementing a Campus Decarbonization Plan .” ASHRAE Journal ( 8 ). 2 . Butbul , Y . 2022 . “ Decarbonization Solutions for Existing Hot Water Systems .” Engineered Systems ( 3 ). https :// tinyurl . com / swnb822z 3 . EPA . Undated . “ Power Profiler .” U . S . Environmental Protection Agency . https :// tinyurl . com / 3pb4dp8r 4 . Energy Star . 2022 . “ Greenhouse Gas Emissions .” Energy Star . https :// tinyurl . com / 4n4nx3vh
+ 13