SBIR Phase I: High Efficiency Thermoelectric Converter

Nanoconversion Technologies, Inc., San Jose CA

Investigators

Abstract

This Small Business Innovation Research Phase I project is intended to establish the feasibility of a 30% efficient electric power generator called the C-TEC, for Concentration-mode Thermoelectric Converter. To date, we have built 18 working prototypes, but have none have been suitable for efficiency measurements. The C-TEC directly generates electricity from heat using a thermally regenerated concentration gradient across an electrolyte membrane, rather than a thermal gradient across a semiconductor material, which offers the potential for high efficiency like a fuel cell, with the low cost, maintenance and long life of a thermoelectric device. Ford and NASA have researched the AMTEC, a previous concentration-mode device, since the 1980s. Research papers have used detailed theoretical models and calculations to show the potential for greater than 30% efficiency for these devices, but in practice, only 15% to 19% efficiency has ever been realized. A new design, along with a proprietary, high conductivity electrolyte material, may allow the low cost C-TEC to break the 30% efficiency barrier. The broader impact/commercial potential of this project will be the development of low cost, high efficiency generators that can operate on any form of heat in a wide variety of applications. C-TEC generators are inherently more versatile than other technologies that require high-grade, specific fuels, such as engines (gasoline), turbines (natural gas), fuel cells (hydrogen), or solar cells (sunlight). The C-TEC makes no noise, has no moving parts and requires no maintenance, making it ideal for long-term power generation. Clean, distributed electricity provided by microCHP (Combined Heat and Power systems at less than 5 kW electrical power) enables breakthrough electrical efficiency in the home, and will be a critical technology for the widespread adoption of the electric car. The C-TEC-powered electric car will use domestic natural gas as a bridge to renewables, reducing dependence on foreign oil and massive infrastructure development costs associated with upgrades to our grid capacity. Other technologies have been proposed as prime drivers for microCHP, including fuel cells and engines, but these fall short in terms of cost and maintenance. Ultimately, the cost and versatility of the C-TEC will provide economic advantages such as fast payback to drive the adoption of new clean technologies.