Laipradit, P; Tiansuwan, J; Kiatsiriroat, T & Lu Aye 2006 'Life cycle cost of CO2 heat pump water heater: Application in Thailand', ICGSI2006, International Conference on Green and Sustainable Innovation: Integrated Approaches for Sustainable Society, 29 November - 1 December 2006, Chiang Mai, pp. 437-42.
Abstract
The optimisation of an air source CO2 heat pump water heater to minimise the life cycle cost (LCC) of the system is presented. The design parameters investigated were compressor capacity, heat transfer area of gas cooler and heat transfer area of evaporator. The developed computer simulation model developed, REFPROP7 and, a numerical routine available of-the-shelf are used. The heating capacity of the domestic water heater investigated is 4 kW and the daily operating time is two hours. The costs of the equipment and the current electricity charge in Thailand are employed in the numerical optimisation. The assumed life span of the system is 10 years. The minimum LCC of the investigated domestic heater is found to be Baht 115,281. The LCC consists of total initial investment of compressor, gas cooler, evaporator, fan, other miscellaneous components and operating and maintenance costs. The system heating coefficient of performance (COP) is found to be 2.1. The CO2 heat pump water heater with the optimum system design can produce water temperature about 49ºC at a flow rate of 3 L/min and meet the ASHRAE standard for domestic applications.
Keywords: Heat Pump, CO2, Carbon Dioxide, Water Heater, Life Cycle Cost