Designing Solar Powered Air Conditioner


Solar air conditioning refers to any air conditioning system that uses solar power. This can be done through solar thermal energy conversion and photovoltaic conversion. Solar air conditioners use energy from the sun to provide some or all of the energy required to produce cooling. Hence, by using solar air conditioners you can either reduce or eliminate the need electricity required for cooling. In air conditioners used for domestic purposes, the electricity required for cooling can be as high as 30-40% of the total electricity used. In commercial complexes, this percentage is even higher. Solar air conditioning can provide significant environmental benefits. Air conditioners are one of the major contributors to peak demand for electricity and solar air conditioners offer the benefit of peak load shifting in addition to the reduction in total energy requirement thereby reducing stress on the grid.


Components Needed:

  • Solar Panel
  • Pure Sine Wave Inverter Circuit (240v to 12v)
  • Charge Controller Circuit
  • Battery
  • Domestic Air Conditioner ( only evaporator and its circuits )
  • Domestic Refrigerator ( Compressor, Condenser and its circuits )
  • Refrigerants


Block diagram of Proposed Air Conditioner:





This project proposes the design and implementation of the Solar Powered Air Conditioning (A/C) System. A conventional A/C consumes more electrical power for it cooling operation, which increases the electricity bill and also paves the way for electric power demand. When the conventional A/C is fully designed using solar technology, the cost is not affordable, because conventional A/C requires running current of 5-6 Ampere, during this condition high wattage solar panel is required. When compared to conventional A/C system, the proposed model of the solar air conditioner is very much cost effective. It is achieved by replacing the existing AC compressor (1230 watts) with refrigerator compressor (300 watts). The compressor in conventional A/C has a starting current of 17 A, for which power required is 3910 Watts which increases the solar panel cost. But refrigerator compressor has a starting current of 1A, for which 100 Watts solar panel can be used for effective performance. In this model, the AC indoor unit is connected to the evaporator coil and compressor to give a comfortable cooling. Initially, the proposed model refrigerator compressor is fed with R12 (CFC) as a coolant, which leads to global warming and ozone layer depletion. Later on, R12 is replaced to R134a (HFC) by changing the compressor oil from mineral oil to synthetic oil. In Solar A/C, solar energy is trapped by 12V, 100 Watts solar panel and stored in the 12V, 55Ah battery using the Maximum Power Point Tracker (MPPT) charge controller. This stored battery DC power is converted to 230 V AC power using an inverter which supplies the refrigerator compressor. Thus the proposed model of Solar Air Conditioner with reduced power rating is more economic and eco-friendly.



  • A Solar A/C can reduce the electricity cost and thereby it will be the one-time investment equipment.
  • As the Federal and State Government offers incentives for solar panel, this system is economic.
  • Low maintenance of Solar panel and effective cooling.



  • Any solar based system is weather dependent and hence during winter, its efficiency is about 10-15% only.
  • For the optimum utilization of energy from the sun, the tracking system is needed.
  • Solar A/C needs a charge controller, a battery and an inverter setup.