In its ever-expanding quest for new energy-efficient devices, the Army Research Laboratory has been applying the thermoelectric effect to an M1 Abrams tank, and the project could ripple out into every nook and cranny of the civilian sector.
Thermoelectricity basically taps the difference between hot and cold temperatures to generate an electric current, so it could be used to capture excess energy from vehicle exhaust and other engines, factory equipment, and anything else that normally vents heat into the atmosphere. That includes the human body, too.
Thermoelectricity and Cogeneration
If you’re wondering why cogeneration can’t get the job done, that’s a good question. Cogeneration systems are typically used to capture waste heat from relatively large, stationary facilities, but they’re not the best solution for things on the move, including vehicles, aircraft, watercraft, and people.
Cogeneration systems also aren’t a particularly economical solution for small facilities and standalone devices.
Thermoelectric systems, on the other hand, can be scaled down to a relatively low cost and portable size (“highly miniaturized” is the way Army researchers describe it) because they are based on atomic-level interactions between adjacent materials.
The trick is to identify thermoelectric materials that provide the most electrical bang for the buck.
Thermoelectric Power from an Abrams Tank
GM has been working on a thermoelectric system for capturing waste heat from car exhaust, so it’s no surprise that the company is a partner in the Abrams tank project along with General Dynamics, Creare, Inc. (a heat transfer expert), and the international research group Research Triangle Institute.
So far the project has produced a small-scale, 80-watt prototype system on the exhaust heat of the tank. The next step will be to scale up the system to full size.
By way of demonstrating another advantage of thermoelectric power systems, the tank will be retrofitted without any modifications to its existing engine or powertrain.
Many Applications for Thermoelectric Power
According to an Army article about the Abrams project, thermoelectric power is especially suited for military use “because it has no moving parts, low weight, modularity, covert and silent, high power density, low amortized cost and long service life with no required maintenance.”
For what it’s worth, that makes it ideal for drones and other small-scale devices.
However, though the Army is focused on military purposes, the Abrams project has been developed along the lines of a “systems engineering approach,” meaning that lessons learned from developing a thermoelectric device for one specific application could be transferred to any number of new purposes.
Follow me on Twitter: @TinaMCasey
Tina Casey specializes in military and corporate sustainability, advanced technology, emerging materials, biofuels, and water and wastewater issues. Tina’s articles are reposted frequently on Reuters, Scientific American, and many other sites. You can also follow her on Twitter @TinaMCasey and Google+.