SBIR Phase I: Refrigerant-free heat pump using high-performance thermoelectric materials and methods

The broader impact of this Small Business Innovation Research (SBIR) Phase I project is through the development of a more efficient and cost-competitive solid-state heat pump technology for heating and cooling. Buildings are one of the largest contributors to carbon emissions, substantially associated with heating, cooling, and domestic hot water production. As an all- electric technology, solid-state heat pumps can easily be powered directly by renewable power, such as solar or wind. This would not only reduce reliance on fossil fuels but will also contribute to the sustainable electrification of the built environment that is necessary to mitigate the effects of climate change. This refrigerant-free technology may also avoid refrigerant leaks that contribute to climate change. As a retrofit, it would enable multifamily residential buildings to comply with the emerging more stringent carbon emission standards. In New York City alone, this represents a potential $2.2 B market. This project aims to increase the efficiency and cost-effectiveness of traditional solid-state heat pumps based on thermoelectric energy conversion by leveraging new thermoelectric materials and modern manufacturing processes to surpass the performance of traditional vapor-compression heat pumps. The approach aims to integrate the active components of thermoelectric heat pumps, specifically the thermoelectric legs and electrodes, directly and in intimate thermal contact with active heat exchanger surfaces leveraging ink-based thermoelectric systems with high figure of merit. The proposed configuration and manufacturing process minimizes the deleterious interface and heat pump substrate thermal resistances, increasing the system performance. A multi-disciplinary team will integrate scalable fabrication processes for thermoelectric materials using sintering with printable electronics on metal core substrates. The goal of this project is to determine the feasibility of the approach by building and testing a representative assembly that can be easily scaled up to provide larger heating and cooling capacities. This approach constitutes a radical redesign to how thermoelectric systems are assembled, unlocking new opportunities toward delivering sustainable and scalable solutions for heating and cooling. This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria.