Enhancing Cost-efficiency Trade-off for Thermoelectric Air Conditioning System in Oyo State, Nigeria

Abstract

A variable speed thermoelectric (TE) air conditioner system is developed for efficient power management using intelligent control system. The investigation adopted Variable Voltage Variable Frequency (VVVF) regulator mode of a solid state electronic conversion system with integration of AC–DC and DC–AC Converter method. The system received power from the main 230VAC source and a step-down transformer converted it to 150VAC. The bridge rectifier converted the output voltage varying DCV by regulating the frequency. The DC voltage is transformed back into AC through Pulse Width Modulation (PWM) technique. The sinusoidal waveform is formed automatically by programmed microcontroller (PIC18F4431) Insulated Gate Bipolar Transistor (IGBT) inverter that fed the air conditional compressor motor. The investigational results revealed that as the frequency declines, speed and torque drop which resulted to substantial reduction of power intake. The study reveals that 80,280kWh of energy is expended by a conventional air conditioner (CAC) in a month under steady operation while 15,624kWh is consumed by a thermoelectric air conditioner (TEAC) at the same period. This translates to energy cost of 602,100 NGN (387.51 USD) and 18,063,000 NGN (11625.27 USD) by conventional air conditioner (CAC) daily and monthly respectively while TEAC accounts for 117,180 NGN (75.42 USD) and 3,515,400 NGN (2262.50 USD) at the same period correspondingly. The energy savings cost with the developed TE drive are ₦484,920 ($312.09), ₦14,547,600 ($9362.78) and ₦174,571,200 ($112353.31) averagely on daily, monthly and yearly respectively. The estimated electricity in the study shows that 67% of the energy and cost bill is saved periodically using the developed TE drive likened to traditional climate control system.