Efficiency of Electricity Production from Installed Generator on a Condensing Unit of an Air Conditioner

Abstract

This research investigated the efficiency of a generator installed on a condensing unit to produce electricity on a split air conditioner. A rectangle-shaped or a circular-shaped hood was set up to increase the wind speed coming out of the condensing unit. A DC generator with a capacity of 24 Volts and 300 Watts was operated at the end of each hood to produce electricity. All experiments were performed using a split-typed air conditioner within a 3.0 m X 3.0 m X 2.6 m room. The air conditioner was set to 25 °C in the cool mode with the fan speed set to level 5. The results showed that the average air ventilation speed of the condensing unit, the end of rectangle-shaped hood and the end of circle-shaped hood is at approximately 7.6, 12.4 and 12.5 m/s, respectively. The electrical generator operated just outside of the normal condensing unit, the end of rectangle-shaped hood and the end of circle-shaped hood had a voltage of 7.9, 15.6 and 16.1 V, and daily average electricity of 491.8, 1951.9 and 2071.6 W·hr was produced, respectively. To investigate the COP and EER, 4 cases were used: the normal condensing unit, installation of the electrical generator, installation of rectangle shaped hood and the electrical generator, and installation of circle-shaped hood and the electrical generator. Coefficient of performance in each case was 4.1, 4.1, 4.1 and 4.1, and the energy efficiency ratio of the 4 cases was 14.0, 14.0, 14.0 and 14.0 BTU/W·hr, respectively. The installation of the rectangle-shaped and circle-shaped hoods can increase the potential of the electrical energy production with no impact on the efficiency of the air conditioner.