Projects
Cooling Load Profile indicating modes of plant operation .
Thermal Modelling conducted on the building .
ICE STORAGE SELECTION The ice storage system was selected based on Net Present Value ( NPV ) calculations performed against conventional systems to illustrate what the return on investment would be by implementing such a system . The result was positive and well received by the client who supported the implementation thereof . The supplier was very forthcoming in terms of assisting with the selection of the ice storage vessels based on the design load profiles and discharge capacities .
Considering there are many options in terms of ice storage vessel design , we were looking for a solution which is a modular , low profile design that could be installed on the roof plant areas . The Ice-on-Coil solution was identified as being a best option as it met all these requirements . It was also favoured by the structural engineers due to the impact on the roof slab design considering the load is spread evenly instead of large point loads as other solutions would have had .
IMPACT ON ELECTRICAL USAGE , EFFICIENCY AND SUSTAINABLE ELEMENTS By employing the thermal storage principle , the electrical peak demand was reduced by approximately 30 % and due to the load shifting principle , 50 % of total cooling kWh was shifted to off-peak electrical tariff periods , significantly reducing the energy cost of the system .
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RACA Journal I November 2020 www . hvacronline . co . za