Investigation of Power Generation from Air Conditioning Waste Heat Towards Sustainable Cooling Solution

Air conditioning systems release significant waste heat that can reach up to 90°C during operation presenting an opportunity for energy recovery. Thermoelectric generators (TEGs), leveraging the Seebeck effect potentially to convert the heat into electricity with efficiency enhanced by maintaining a large temperature gradient. This research explores the potential of generating electricity from the waste heat of air-conditioners, addressing the growing demand for sustainable energy solutions. Utilizing thermoelectric generators (TEGs), the study evaluates the feasibility of converting waste heat into electricity using Seebeck effect. An experimental setup was developed to measure waste heat output, with simulations validating the concept. Two prototypes were constructed which is aircooled model and water-cooled model and equipped with commercial Bi<sub>2</sub>Te<sub>3</sub>-based TEG modules. The water-cooled prototype based on water pump circulation demonstrated superior performance, generating a net power output of 1.45 W, compared to 0.05 W for the air-cooled prototyped that made of DC fan and supplied with the exhaust air temperature ranges 85 – 90° C on the hot side and maintained at 20 – 23° C on the cold side. The net power generation was calculated by accounting for the energy consumed by the cooling systems. Scaling the water-cooled design to the dimensions of a typical household air-conditioner resulted in an estimated efficiency improvement of 2.8%, significantly reducing the electricity consumption and promoting environmental sustainability. This study highlights the potential of integrating waste heat recovery into air-conditioning systems, offering a promising pathway toward energy-efficient and eco-friendly solutions.