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SED Associates Corp Consulting Engineers Option 3 — Solar Assisted Heat Pump Water Heater This option uses a refrigerant based heat pump with an external evaporator to either extract/reject heat into the exterior ambient. This option would use one solar assisted heat pump, two (2) exterior wall mounted evaporators panels, two (2) internal storage tanks and an electric back-up tank. The available space within the building is assumed sufficient to accommodate the proposed interior heat pump and tanks. The issue with this application in the lack of operating and support history in the United States. This is a UK product that has been used for several years without significant issues according to the local representative. For specific product understanding and its application for this analysis SED engaged a specialized firm for this application see attached selection. Estimated annual saving compared to electric resistance is 6,484KWH/annual x $0.23= $1,426 Approximate Construction Cost: $18,550(does not include rebates) 5,500 electrical work $24,050 total Option 4 — Instantaneous Electric Water Heater This option would require the installation of multiple heaters to handle the number of fixtures. Assuming a heater that would be able to handle the flow rate of 140°F hot water to produce the 110°F mixed shower water temperature, a flow rate of 10.5 GPM is needed. This would require two(2) heaters each with a 32 kW heating element. Also, the hot water piping for the showers would need to be modified to separate the heaters to accommodate three showers per heater. The issue with this option is the electric power required to supply them. Each unit requires 133 amps of 208/3/60 power, which would go above what is available on the existing service and therefore would require an electrical service upgrade, new panel, and additional circuit wiring for the new water heaters. Option 5 — CO2 Heat Pump Water Heater This option would use the latest technology for water heating on the market. This system uses an Eco friendly refrigerant R744 (i.e., CO2) has an Oxygen Depletion Potential (ODP) of 0 and low Global Warming Potential (GWP) of 1, is non-toxic and non-flammable and provides a long-lasting refrigerant option to increasingly stringent environmental guidelines. This system has a COP of 3.8. This system would require the use of an exterior mounted heat pump water heater coupled to an exterior heat exchanger module, exterior 150 water storage tank and a 50. gallon swing tank with an 18 -kW electric heating element. The main water storage tank is approximately 50" in diameter and from field measurements made might not fit into the space available inside the mechanical space. The swing tank would be installed where the existing oil -fired water heater currently resides within the pool equipment room. Most of the equipment would need to be installed on the exterior of the building a covered area such as a doghouse shed, would be required to protect the equipment from the elements. This option uses the lowest amount of electricity (16.1 kW) than the other electric driven options and therefore, will provide the lowest operation cost. Also, based on demand, the system could have enough storage capacity on a normal use day so that the heat pump could be operated at night when