Performance assessment of a new energy harvesting system using thermoelectric generator coupled with solar radiation on hybrid nanofluids

Combining energy recovery and renewable energy technologies for energy harvesting systems is a real challenge. In the present study, an innovative new energy harvesting (NEH) system by utilizing the exhaust airflow of all-air heating, ventilating, and air-conditioning systems, and implementation of the solar irradiation on the various hybrid nanofluid, integrated on the other side of the TEG system is investigated. The parametric studies for performance assessment with economic and environmental concerns have been presented based on the one-dimensional steady-state and heat diffusion equation. The thermal modeling result revealed the most promising configuration for the NEH system observed with solar radiation of 1700 W m−2 incident on 1% vol. fraction of Al2O3-Cu/EG brine hybrid nanofluid and the relative fraction of exhausted air of 0.3 with cooling load variation from 30 to 400 kW. With this configuration, the energy saved increases by 28%, and a nearly 1.2-ton reduction in CO2 is observed for the environmental concern. The most acceptable payback period is less than 5 years with a cooling load greater than 100 kW. However, with economic concerns, a 20% increase in power generation, the money saved increased by 31.25% per month for cooling load variation from 30 to 400 kW for the NEH system. Hence, the solar radiation variation and low exhaust air fraction have a high impact on energy saving compared to a low result of the cooling load.