In this paper, an experimental investigation of a traveling-wave thermoacoustic electricity generator, which consists of a traveling-wave thermoacoustic heat engine and a linear alternator driven by that engine, is presented. Using the results of previous theoretical and experimental research, we designed and fabricated a traveling-wave thermoacoustic heat engine and a linear alternator. In the experiments, 450.9 W of electrical power was obtained with a maximum thermal-to-electrical efficiency of 15.03%, and a maximum electrical power of 481.0 W was achieved with 12.65% thermal-to-electrical efficiency.

Energy crisis and environmental pollution have become global issues. This study reported a heat-driven combined cooling and heating system based on thermoacoustic technology, which adopted two units of thermoacoustic engine and cooler cores to improve the efficiency. This system can be used as a refrigerator and a heat pump at the same time. Experimental results showed that with a charging pressure of 10 MPa, a high temperature of 300 °C, and a medium temperature of 45 °C, cooling power ranging from 0.61 to 3.89 kW and coefficient of performance varying from 0.08 to 0.30 with low temperature changing from −30 to −5 °C were achieved when the system was working as a refrigerator. Meanwhile, under a low temperature of −30 and −10 °C, a heating power of 7.85 and 14.3 kW with a medium temperature of 45 °C could be achieved corresponding to a coefficient of performance of 1.08 and 1.24 when the system was working as a heat pump. These experimental performances show remarkable advantages and a promising prospect for thermal energy utilization in the future.

A thermoacoustic heat engine (TAHE) is a type of regenerative heat engine that converts external heat into mechanical power in the form of an acoustic wave with no moving mechanical components. One significant application of the TAHE is the generation of electricity by coupling an acoustic-to-electric conversion unit such as a linear motor or a piezoelectric ceramic assembly. However, present-day conversion technologies have considerable drawbacks, including structural complexity, high cost, and low reliability. The advent of triboelectric nanogenerators (TENGs) offers an alternative means to overcoming these shortcomings. In this paper, we propose a thermoacoustically driven TENG (TA-TENG) that continuously harvests external heat. A test rig involving a standing-wave TAHE and a contact-separation mode TENG was fabricated to demonstrate this concept. Currently, the TA-TENG produces a maximum output voltage of 10 V and a corresponding output power of 0.008 μW with a load of 400 MΩ, demonstrating the viability of this hybrid combination for electricity generation.