Engineers at the Office of Naval Research and Massachusetts Institute of Technology (MIT) have devised a small and portable system capable of measuring electricity consumption. From the Navy’s standpoint, the technology will help troops in forward operating areas and sailors on ships to keep tabs on energy usage. The efficiencies they realize could mean fewer replenishments — which could translate into lives saved. In the public sector, the system will make it easier to track how much electricity is used by appliances, lights, and devices.