One of the most enthusiastic supporters of microengines is DARPA in Washington, DC. William Tang, the agency’s program manager for MEMS research, believes that a power source built into a silicon chip would be extremely useful on the battlefield. One device being studied is a sensor no larger than a sugar cube that contains all the wireless communications and data storage circuitry along with the power supply.

A microengine generating up to 50 milliwatts would be enough to power such a sensor as it collected information from its surroundings and beamed the data up to a low-flying aircraft. Hundreds of sugar-cube sensors could be scattered over the terrain and left to monitor ground vibrations and temperature changes for months on end.
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